The application of encapsulation material stability data to photovoltaic module life assessment
NASA Technical Reports Server (NTRS)
Coulbert, C. D.
1983-01-01
For any piece of hardware that degrades when subject to environmental and application stresses, the route or sequence that describes the degradation process may be summarized in terms of six key words: LOADS, RESPONSE, CHANGE, DAMAGE, FAILURE, and PENALTY. Applied to photovoltaic modules, these six factors form the core outline of an expanded failure analysis matrix for unifying and integrating relevant material degradation data and analyses. An important feature of this approach is the deliberate differentiation between factors such as CHANGE, DAMAGE, and FAILURE. The application of this outline to materials degradation research facilitates the distinction between quantifying material property changes and quantifying module damage or power loss with their economic consequences. The approach recommended for relating material stability data to photovoltaic module life is to use the degree of DAMAGE to (1) optical coupling, (2) encapsulant package integrity, (3) PV circuit integrity or (4) electrical isolation as the quantitative criterion for assessing module potential service life rather than simply using module power loss.
An Integrated, Problem-Based Learning Material: The "Satellite" Module
ERIC Educational Resources Information Center
Selcuk, Gamze Sezgin; Emiroglu, Handan Byacioglu; Tarakci, Mehmet; Ozel, Mustafa
2011-01-01
The purpose of this study is to introduce a problem-based learning material, the Satellite Module, that has integrated some of the subjects included in the disciplines of physics and mathematics at an introductory level in undergraduate education. The reason why this modular and problem-based material has been developed is to enable students to…
NASA Astrophysics Data System (ADS)
Ma, Zhizhen; Hemnani, Rohit; Bartels, Ludwig; Agarwal, Ritesh; Sorger, Volker J.
2018-02-01
Here we discuss the physics of electro-optic modulators deploying 2D materials. We include a scaling laws analysis and show how energy-efficiency and speed change for three underlying cavity systems as a function of critical device length scaling. A key result is that the energy-per-bit of the modulator is proportional to the volume of the device, thus making the case for submicron-scale modulators possible deploying a plasmonic optical mode. We then show how Graphene's Pauli-blocking modulation mechanism is sensitive to the device operation temperature, whereby a reduction of the temperature enables a 10× reduction in modulator energy efficiency. Furthermore, we show how the high-index tunability of graphene is able to compensate for the small optical overlap factor of 2D-based material modulators, which is unlike classical silicon-based dispersion devices. Lastly, we demonstrate a novel method towards a 2D material printer suitable for cross-contamination free and on-demand printing. The latter paves the way to integrate 2D materials seamlessly into taped-out photonic chips.
NASA Astrophysics Data System (ADS)
Rademacher, L. K.
2017-12-01
The Interdisciplinary Teaching about Earth for a Sustainable Future (InTeGrate) community has developed extensive courses and modules designed for broad adoption into geoscience classrooms in diverse environments. I participated in a three-semester research project designed to test the efficacy of incorporating "high doses" (minimum 3 modules or 18 class periods) of InTeGrate materials into a course, in my case, an introductory environmental science class. InTeGrate materials were developed by groups of instructors from a range of institutions across the US. These materials include an emphasis on systems thinking, interdisciplinary approaches, and sustainability, and those themes are woven throughout the modules. The three semesters included a control in which no InTeGrate materials were used, a pilot in which InTeGrate materials were tested, and a treatment semesters in which tested materials were modified as needed and fully implemented into the course. Data were collected each semester on student attitudes using the InTeGrate Attitudinal Instrument (pre and post), a subset of Geoscience Literacy Exam questions (pre and post), and a series of assessments and essay exam questions (post only). Although results suggest that learning gains were mixed, changes in attitudes pre- and post-instruction were substantial. Changes in attitudes regarding the importance of sustainable employers, the frequency of self-reported individual sustainable actions, and motivation level for creating a sustainable society were observed in the control and treatment semesters, with the treatment semester showing the greatest gains. Importantly, one of the biggest differences between the control and treatment semesters is the reported impact that the course had on influencing students' sustainable behaviors. The treatment semester course impacted students' sustainable behaviors far more than the control semester.
Integral bypass diodes in an amorphous silicon alloy photovoltaic module
NASA Technical Reports Server (NTRS)
Hanak, J. J.; Flaisher, H.
1991-01-01
Thin-film, tandem-junction, amorphous silicon (a-Si) photovoltaic modules were constructed in which a part of the a-Si alloy cell material is used to form bypass protection diodes. This integral design circumvents the need for incorporating external, conventional diodes, thus simplifying the manufacturing process and reducing module weight.
All-optical liquid crystal spatial light modulators
NASA Astrophysics Data System (ADS)
Tabiryan, Nelson; Grozhik, Vladimir; Khoo, Iam Choon; Nersisyan, Sarik R.; Serak, Svetlana
2003-12-01
Nonlinear optical processes in liquid crystals (LC) can be used for construction of all-optical spatial light modulators (SLM) where the photosensitivity and phase modulating functions are integrated into a single layer of an LC-material. Such spatial light integrated modulators (SLIMs) cost only a fraction of the conventional LC-SLM and can be used with high power laser radiation due to high transparency of LC materials and absence of light absorbing electrodes on the substrates of the LC-cell constituting the SLIM. Recent development of LC materials the photosensitivity of which is comparable to that of semiconductors has led to using SLIM in schemes of optical anti-jamming, sensor protection, and image processing. All-optical processes add remarkable versatility to the operation of SLIM harnessing the wealth inherent to light-matter interaction phenomena.
NASA Astrophysics Data System (ADS)
Amin, Rubab; Suer, Can; Ma, Zhizhen; Sarpkaya, Ibrahim; Khurgin, Jacob B.; Agarwal, Ritesh; Sorger, Volker J.
2017-10-01
Electro-optic modulation is a key function in optical data communication and possible future optical computing engines. The performance of modulators intricately depends on the interaction between the actively modulated material and the propagating waveguide mode. While high-performing modulators were demonstrated before, the approaches were taken as ad-hoc. Here we show the first systematic investigation to incorporate a holistic analysis for high-performance and ultra-compact electro-optic modulators on-chip. We show that intricate interplay between active modulation material and optical mode plays a key role in the device operation. Based on physical tradeoffs such as index modulation, loss, optical confinement factors and slow-light effects, we find that bias-material-mode regions exist where high phase modulation and high loss (absorption) modulation is found. This work paves the way for a holistic design rule of electro-optic modulators for on-chip integration.
NASA Technical Reports Server (NTRS)
1991-01-01
Optoelectronic materials and devices are examined. Optoelectronic devices, which generate, detect, modulate, or switch electromagnetic radiation are being developed for a variety of space applications. The program includes spatial light modulators, solid state lasers, optoelectronic integrated circuits, nonlinear optical materials and devices, fiber optics, and optical networking photovoltaic technology and optical processing.
The 19th Project Integration Meeting
NASA Technical Reports Server (NTRS)
Mcdonald, R. R.
1981-01-01
The Flat-Plate Solar Array Project is described. Project analysis and integration is discussed. Technology research in silicon material, large-area silicon sheet and environmental isolation; cell and module formation; engineering sciences, and module performance and failure analysis. It includes a report on, and copies of visual presentations made at, the 19th Project Integration Meeting held at Pasadena, California, on November 11, 1981.
Proceedings of the 21st Project Integration Meeting
NASA Technical Reports Server (NTRS)
1983-01-01
Progress made by the Flat Plate Solar Array Project during the period April 1982 to January 1983 is described. Reports on polysilicon refining, thin film solar cell and module technology development, central station electric utility activities, silicon sheet growth and characteristics, advanced photovoltaic materials, cell and processes research, module technology, environmental isolation, engineering sciences, module performance and failure analysis and project analysis and integration are included.
ERIC Educational Resources Information Center
Schneiderman, Deborah; Freihoefer, Kara
2012-01-01
Purpose: The purpose of this paper is to examine the integration of Okala curriculum into Interior Design coursework. Okala, as a teaching package, is utilized extensively in industrial design education. However, this study examines the expansion and insertion of Okala modules in an existing interior design curriculum. The Okala modules included…
Gel integration for microfluidic applications.
Zhang, Xuanqi; Li, Lingjun; Luo, Chunxiong
2016-05-21
Molecular diffusive membranes or materials are important for biological applications in microfluidic systems. Hydrogels are typical materials that offer several advantages, such as free diffusion for small molecules, biocompatibility with most cells, temperature sensitivity, relatively low cost, and ease of production. With the development of microfluidic applications, hydrogels can be integrated into microfluidic systems by soft lithography, flow-solid processes or UV cure methods. Due to their special properties, hydrogels are widely used as fluid control modules, biochemical reaction modules or biological application modules in different applications. Although hydrogels have been used in microfluidic systems for more than ten years, many hydrogels' properties and integrated techniques have not been carefully elaborated. Here, we systematically review the physical properties of hydrogels, general methods for gel-microfluidics integration and applications of this field. Advanced topics and the outlook of hydrogel fabrication and applications are also discussed. We hope this review can help researchers choose suitable methods for their applications using hydrogels.
Chalcogenide glass-on-graphene photonics
NASA Astrophysics Data System (ADS)
Lin, Hongtao; Song, Yi; Huang, Yizhong; Kita, Derek; Deckoff-Jones, Skylar; Wang, Kaiqi; Li, Lan; Li, Junying; Zheng, Hanyu; Luo, Zhengqian; Wang, Haozhe; Novak, Spencer; Yadav, Anupama; Huang, Chung-Che; Shiue, Ren-Jye; Englund, Dirk; Gu, Tian; Hewak, Daniel; Richardson, Kathleen; Kong, Jing; Hu, Juejun
2017-12-01
Two-dimensional (2D) materials are of tremendous interest to integrated photonics, given their singular optical characteristics spanning light emission, modulation, saturable absorption and nonlinear optics. To harness their optical properties, these atomically thin materials are usually attached onto prefabricated devices via a transfer process. Here, we present a new route for 2D material integration with planar photonics. Central to this approach is the use of chalcogenide glass, a multifunctional material that can be directly deposited and patterned on a wide variety of 2D materials and can simultaneously function as the light-guiding medium, a gate dielectric and a passivation layer for 2D materials. Besides achieving improved fabrication yield and throughput compared with the traditional transfer process, our technique also enables unconventional multilayer device geometries optimally designed for enhancing light-matter interactions in the 2D layers. Capitalizing on this facile integration method, we demonstrate a series of high-performance glass-on-graphene devices including ultra-broadband on-chip polarizers, energy-efficient thermo-optic switches, as well as graphene-based mid-infrared waveguide-integrated photodetectors and modulators.
Flat Plate Solar Array Project: Proceedings of the 20th Project Integration Meeting
NASA Technical Reports Server (NTRS)
Mcdonald, R. R.
1982-01-01
Progress made by the Flat-Plate Solar Array Project during the period November 1981 to April 1982 is reported. Project analysis and integration, technology research in silicon material, large-area silicon sheet and environmental isolation, cell and module formation, engineering sciences, and module performance and failure analysis are covered.
Digital fabrication of multi-material biomedical objects.
Cheung, H H; Choi, S H
2009-12-01
This paper describes a multi-material virtual prototyping (MMVP) system for modelling and digital fabrication of discrete and functionally graded multi-material objects for biomedical applications. The MMVP system consists of a DMMVP module, an FGMVP module and a virtual reality (VR) simulation module. The DMMVP module is used to model discrete multi-material (DMM) objects, while the FGMVP module is for functionally graded multi-material (FGM) objects. The VR simulation module integrates these two modules to perform digital fabrication of multi-material objects, which can be subsequently visualized and analysed in a virtual environment to optimize MMLM processes for fabrication of product prototypes. Using the MMVP system, two biomedical objects, including a DMM human spine and an FGM intervertebral disc spacer are modelled and digitally fabricated for visualization and analysis in a VR environment. These studies show that the MMVP system is a practical tool for modelling, visualization, and subsequent fabrication of biomedical objects of discrete and functionally graded multi-materials for biomedical applications. The system may be adapted to control MMLM machines with appropriate hardware for physical fabrication of biomedical objects.
Design and Application of Integrated Assembly Technology of FRG in Residential Ceiling
NASA Astrophysics Data System (ADS)
Li, Xiuyun; Yu, Changyong
2018-06-01
FRG material is a new environmentally friendly indoor decoration materials and popular in prefabricated construction, the paper introduces the performance and design of materials, and takes FRG in the residential ceiling integrated assembly process into a demonstration project, which showed that FRG in the prefabricated modules integrated ceiling of the whole template scheme has a great artistry and application effect. Meanwhile it provides reference for the integrated ceiling assembly modular process design of similar indoor decoration.
NASA Astrophysics Data System (ADS)
Hidayati, A.; Rahmi, A.; Yohandri; Ratnawulan
2018-04-01
The importance of teaching materials in accordance with the characteristics of students became the main reason for the development of basic electronics I module integrated character values based on conceptual change teaching model. The module development in this research follows the development procedure of Plomp which includes preliminary research, prototyping phase and assessment phase. In the first year of this research, the module is validated. Content validity is seen from the conformity of the module with the development theory in accordance with the demands of learning model characteristics. The validity of the construct is seen from the linkage and consistency of each module component developed with the characteristic of the integrated learning model of character values obtained through validator assessment. The average validation value assessed by the validator belongs to a very valid category. Based on the validator assessment then revised the basic electronics I module integrated character values based on conceptual change teaching model.
NASA Astrophysics Data System (ADS)
Wu, Chi; Keo, Sam A.; Yao, X. S.; Turner, Tasha E.; Davis, Lawrence J.; Young, Martin G.; Maleki, Lute; Forouhar, Siamak
1998-08-01
The microwave optoelectronic oscillator (OEO) has been demonstrated on a breadboard. The future trend is to integrate the whole OEO on a chip, which requires the development of high power and high efficiency integrated photonic components. In this paper, we will present the design and fabrication of an integrated semiconductor laser/modulator using the identical active layer approach on InGaAsP/InP material. The best devices have threshold currents of 50-mA at room temperature for CW operation. The device length is approximately 3-mm, resulting in a mode spacing of 14 GHz. For only 5-dBm microwave power applied to the modulator section, modulation response with 30 dB resonate enhancement has been observed. This work shows the promise for an on-chip integrated OEO.
Ground Vehicle Power and Mobility Overview
2007-05-30
Program Li-Ion Phosphate (LFP) Cathode Materials Large Format Li-Ion Prismatic Cells and Modules with Integrated Liquid Cooling Integrated Prototype...using porous graphitic material3 4 5 8 5 6 60 W-hr/kg 80-120 W/kg Low Cycle Life LFP cathode Safer Less energetic materials ~ ~ Power Cell 85-120...Thermal Runaway Study Zebra Battery NaNiCl2 (FY08 ATO) Advanced Lead Acid LiFePO4 Cathode Prismatic Lithium-ion batteries and Integrated Liquid Cooling
NASA Astrophysics Data System (ADS)
Bruckner, M. Z.; Birnbaum, S. J.; Bralower, T. J.; Egger, A. E.; Fox, S.; Gosselin, D. C.; Iverson, E. A. R.; Manduca, C. A.; Mcconnell, D. A.; Steer, D. N.; Taber, J. J.
2016-12-01
InTeGrate is dedicated to providing robust curricular materials that increase Earth literacy among undergraduate students. As of August 2016, 14 modules that use an interdisciplinary approach to teach about Earth-related sustainability issues across the curriculum have been published, and 19 courses and modules are undergoing final revisions. Materials are designed for undergraduate courses and have been tested in a variety of disciplines including geoscience, engineering, humanities, ethics, and Spanish language courses. The materials were developed, tested, revised, and reviewed using a two-year, highly scaffolded process that involves meeting a series of checkpoints, and is supported by a team of experts who provide guidance and formative feedback throughout the process. A series of webinars also supported teams in the development process. Author teams comprise 3-6 faculty members from at least three different institutions. Authors work collaboratively in a templated webspace designed specifically for creating materials, and representatives from the InTeGrate leadership, assessment, and web teams support each group of authors. This support team provides guidance and feedback on content, pedagogy, and web layout as authors develop materials. Authors attend two face-to-face meetings, one at the beginning of the process and another after materials are piloted in authors' classes. These meetings serve to initially orient authors to the development process, including the rubric that will guide their work, and in making revisions following the piloting phase of the project. Authors report that the meetings also provide professional development experience wherein they learn about pedagogy from each other and team leaders. The bulk of the materials development occurs remotely, with teams meeting regularly via teleconference as they follow the project timeline. All materials undergo review against the Materials Design and Refinement Rubric to ensure they meet project goals and are of high quality before being piloted in the authors' classes. Subsequent revisions are based on the authors' pilot experiences and feedback from the assessment team as well as an external review. Learn more at: serc.carleton.edu/integrate/teaching_materials/modules_courses.html
Plasma Cutting and Carbon-Arc Cutting. Welding Module 8. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching the two units of a module in operating plasma cutting and carbon-arc cutting equipment. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The materials included in the module have been…
NASA Astrophysics Data System (ADS)
Egger, A. E.; Awad, A. A.; Baldwin, K. A.; Birnbaum, S. J.; Bruckner, M. Z.; DeBari, S. M.; Dechaine, J.; Ebert, J. R.; Gray, K. R.; Hauge, R.; Linneman, S. R.; Monet, J.; Thomas, J.; Varrella, G.
2014-12-01
As part of InTeGrate, teams of 3 instructors at 3 different institutions developed modules that help prepare pre-service teachers to teach Earth science aligned with the NGSS. Modules were evaluated against a rubric, which addresses InTeGrate's five guiding principles, learning objectives and outcomes, assessment and measurement, resources and materials, instructional strategies and alignment. As all modules must address one or more Earth-related grand challenge facing society, develop student ability to address interdisciplinary problems, improve student understanding of the methods of geoscience, use authentic geoscience data, and incorporate systems thinking, they align well with the NGSS. Once modules passed the rubric, they were tested by the authors in their classrooms. Testing included pre- and post-assessment of geoscience literacy and assessment of student learning towards the module goal; materials were revised based on the results of testing. In "Exploring Geoscience Methods with Secondary Education Students," pre-service science teachers compare geoscientific thinking with the classic (experimental) scientific method, investigate global climate change and its impacts on human systems, and prepare an interdisciplinary lesson plan that addresses geoscience methods in context of a socioscientific issue. In "Soils and Society," pre-service elementary teachers explore societal issues where soil is important, develop skills to describe and test soil properties, and create a standards-based Soils and Society Kit that consists of lessons and supporting materials to teach K-8 students about a soil-and-society issue. In "Interactions between Water, Earth's Surface, and Human Activity," students explore the effects of running water on shaping Earth's surface both over geologic time and through short-term flooding events, and produce a brochure to inform citizens of the impact of living near a river. The modules are freely available at http://serc.carleton.edu/integrate/teaching_materials/modules_courses.html and include Instructor Stories, where each author describes how they adapted the module to their teaching environment. The goal of showing different implementations of the materialst is to facilitate adoption and adaption beyond the team of authors.
Electro-Optic Modulator Based on Organic Planar Waveguide Integrated with Prism Coupler
NASA Technical Reports Server (NTRS)
Sarkisov, Sergey S.
2002-01-01
The objectives of the project, as they were formulated in the proposal, are the following: (1) Design and development of novel electro-optic modulator using single crystalline film of highly efficient electro-optic organic material integrated with prism coupler; (2) Experimental characterization of the figures-of-merit of the modulator. It is expected to perform with an extinction ratio of 10 dB at a driving signal of 5 V; (3) Conclusions on feasibility of the modulator as an element of data communication systems of future generations. The accomplishments of the project are the following: (1) The design of the electro-optic modulator based on a single crystalline film of organic material NPP has been explored; (2) The evaluation of the figures-of-merit of the electro-optic modulator has been performed; (3) Based on the results of characterization of the figures-of-merit, the conclusion was made that the modulator based on a thin film of NPP is feasible and has a great potential of being used in optic communication with a modulation bandwidth of up to 100 GHz and a driving voltage of the order of 3 to 5 V.
Proceedings of the 22nd Project Integration Meeting
NASA Technical Reports Server (NTRS)
1983-01-01
This report describes progress made by the Flat-Plate Solar Array Project during the period January to September 1983. It includes reports on silicon sheet growth and characterization, module technology, silicon material, cell processing and high-efficiency cells, environmental isolation, engineering sciences, module performance and failure analysis and project analysis and integration. It includes a report on, and copies of visual presentations made at the 22nd Project Integration Meeting held at Pasadena, California, on September 28 and 29, 1983.
Using InTeGrate materials to develop interdisciplinary thinking for a sustainable future
NASA Astrophysics Data System (ADS)
Awad, A. A.; Gilbert, L.; Iverson, E. A. R.; Manduca, C. A.; Steer, D. N.
2017-12-01
InTeGrate materials focus on societal grand challenges, sustainability, and interdisciplinary problems through developing geoscientific habits of mind, the use of credible data, and systems thinking. The materials are freely available 2-3 week modules and courses that allow instructors to focus on a wide variety of topics from regulating carbon emissions, changing biosphere, and storms and community resilience to environmental justice, ocean sustainability, and humans' dependence on mineral resources, integrating a variety of relevant interdisciplinary activities throughout. Presented with interdisciplinary approaches, students learn with tools to integrate engineering, policy, economics, and social aspects with the science to address the challenges. Students' ability to apply interdisciplinary approaches to address sustainability problems is made visible through the essays they write as a part of the materials assessment. InTeGrate modules have been adopted and implemented by faculty members interested in sustainability themes and innovative pedagogy, and have reached more than 50,000 students in all 50 states, Puerto Rico, India, and Micronesia. Student data were collected from 533 assessment essays in 57 undergraduate classes. The essays required students to describe a global challenge in an interdisciplinary manner through identifying scientific implications, and connecting it to economic, social and policy decisions. Students also completed a second essay assessing their systems thinking ability, a geoscience literacy exam (GLE), and demographic and attitudinal surveys. Scores for students enrolled in classes using InTeGrate materials were compared to scores from students in similar classes that did not use InteGrate materials. The InTeGrate and control groups had equivalent GLE scores and demographic characteristics. Essay scores for students in InTeGrate introductory or majors courses outperformed students in comparable level control courses as measured by the average interdisciplinary essay scores.
Gas Tungsten Arc Welding. Welding Module 6. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a three-unit module in gas tungsten arc welding. The module has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The basic principles involved in gas tungsten arc welding, supplies, and applications are covered. The materials included…
Active material, optical mode and cavity impact on nanoscale electro-optic modulation performance
NASA Astrophysics Data System (ADS)
Amin, Rubab; Suer, Can; Ma, Zhizhen; Sarpkaya, Ibrahim; Khurgin, Jacob B.; Agarwal, Ritesh; Sorger, Volker J.
2017-10-01
Electro-optic modulation is a key function in optical data communication and possible future optical compute engines. The performance of modulators intricately depends on the interaction between the actively modulated material and the propagating waveguide mode. While a variety of high-performance modulators have been demonstrated, no comprehensive picture of what factors are most responsible for high performance has emerged so far. Here we report the first systematic and comprehensive analytical and computational investigation for high-performance compact on-chip electro-optic modulators by considering emerging active materials, model considerations and cavity feedback at the nanoscale. We discover that the delicate interplay between the material characteristics and the optical mode properties plays a key role in defining the modulator performance. Based on physical tradeoffs between index modulation, loss, optical confinement factors and slow-light effects, we find that there exist combinations of bias, material and optical mode that yield efficient phase or amplitude modulation with acceptable insertion loss. Furthermore, we show how material properties in the epsilon near zero regime enable reduction of length by as much as by 15 times. Lastly, we introduce and apply a cavity-based electro-optic modulator figure of merit, Δλ/Δα, relating obtainable resonance tuning via phase shifting relative to the incurred losses due to the fundamental Kramers-Kronig relations suggesting optimized device operating regions with optimized modulation-to-loss tradeoffs. This work paves the way for a holistic design rule of electro-optic modulators for high-density on-chip integration.
Preliminary Structural Sizing and Alternative Material Trade Study of CEV Crew Module
NASA Technical Reports Server (NTRS)
Bednarcyk, Brett A.; Arnold, Steve M.; Collier, Craig S.; Yarrington, Phillip W.
2007-01-01
This paper presents the results of a preliminary structural sizing and alternate material trade study for NASA s Crew Exploration Vehicle (CEV) Crew Module (CM). This critical CEV component will house the astronauts during ascent, docking with the International Space Station, reentry, and landing. The alternate material design study considers three materials beyond the standard metallic (aluminum alloy) design that resulted from an earlier NASA Smart Buyer Team analysis. These materials are graphite/epoxy composite laminates, discontinuously reinforced SiC/Al (DRA) composites, and a novel integrated panel material/concept known as WebCore. Using the HyperSizer (Collier Research and Development Corporation) structural sizing software and NASTRAN finite element analysis code, a comparison is made among these materials for the three composite CM concepts considered by the 2006 NASA Engineering and Safety Center Composite Crew Module project.
NASA Technical Reports Server (NTRS)
Kephart, Nancy
1992-01-01
The function of the Space Station Furnace Facility (SSFF) is to support materials research into the crystal growth and solidification processes of electronic and photonic materials, metals and alloys, and glasses and ceramics. To support this broad base of research requirements, the SSFF will employ a variety of furnace modules operated, regulated, and supported by a core of common subsystems. Furnace modules may be reconfigured or specifically developed to provide unique solidifcation conditions for each set of experiments. The SSFF modular approach permits the addition of new or scaled-up furnace modules to support the evolution of the facility as new science requirements are identified. The SSFF Core is of modular design to permit augmentation for enhanced capabilities. The fully integrated configuration of the SSFF will consist of three racks with the capability of supporting up to two furnace modules per rack. The initial configuration of the SSFF will consist of two of the three racks and one furnace module. This Experiment/Facility Requirements Document (E/FRD) describes the integrated facility requirements for the Space Station Freedom (SSF) Integrated Configuration-1 (IC1) mission. The IC1 SSFF will consist of two racks: the Core Rack, with the centralized subsystem equipment, and the Experiment Rack-1, with Furnace Module-1 and the distributed subsystem equipment to support the furnace.
Form and Function: An Organic Chemistry Module. Teacher's Guide.
ERIC Educational Resources Information Center
Jarvis, Bruce; Mazzocchi, Paul; Hearle, Robert
This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching organic chemistry. In this book, the diverse field of organic chemistry modules is introduced. The material in this book can be integrated with the other modules in a sequence that helps students to see that chemistry is a unified…
NASA Astrophysics Data System (ADS)
Rechtenwald, Thomas; Frick, Thomas; Schmidt, Michael
The embedding stereolithography is an additive, hybrid process, which allows the construction of highly integrated 3D assemblies for the use in automotive applications. The flexible process of stereolithography is combined with the embedding of functional components and supplemented by the additive manufacturing of electrical or optical conductive structures. This combination of sub-processes implies a high potential regarding the obtainable integration density of mechatronical modules. This work considers basic restrictions, which limit the mechanical stability of the manufactured modules by calculating the superposition of residual and external stress using a thermo-mechanical finite element model and develops a procedure to qualify stereolithography matrix materials for the process of the embedding stereolithography.
Integrated modular teaching in dermatology for undergraduate students: A novel approach
Karthikeyan, Kaliaperumal; Kumar, Annapurna
2014-01-01
Context: Undergraduate teaching in dermatology comprises didactic lectures and clinical classes. Integrated modular teaching is a novel approach, which integrates basic sciences with dermatology in the form of a module. Further the module also incorporates various teaching modalities, which facilitate active participation from students and promotes learning. The pre- and post-test values showed the effectiveness of the integrated module. The students feedback was encouraging. Aims: The aim of this study was to determine the acceptance and opinion of undergraduate students regarding integrated modular teaching as a new teaching aid in dermatology. Settings and Design: This was a descriptive study. Varied teaching methodologies involving multiple disciplines were undertaken in six major undergraduate topics in dermatology for seventh and eighth semester students. Materials and Methods: A total of six modules were conducted over a period of 12 months for students of seventh and eighth semesters. The topics for the various modules were sexually transmitted diseases, acquired immunodeficiency syndrome, oral ulcers, leprosy, connective tissue disorders and psoriasis. Faculty members from different disciplines participated. Pre- and post-test were conducted before and after the modules respectively to gauge the effectiveness of the modules. Results: It was found that almost every student had a better score on the posttest as compared to the pretest. General feedback obtained from the students showed that all of them felt that modular teaching was a more interesting and useful teaching learning experience than conventional teaching. Conclusions: Integrated modular teaching can be an effective adjunct in imparting theoretical and practical knowledge to the students. Further, various teaching methodologies can be used in integrated modules effectively with active student participation. Thus integrated modular teaching addresses two important issues in medical education, namely integration and active student participation. PMID:25165641
Low-power nanophotonics: material and device technology
NASA Astrophysics Data System (ADS)
Thylén, Lars; Holmstrom, Petter; Wosinski, Lech; Lourdudoss, Sebastian
2013-05-01
Development in photonics for communications and interconnects pose increasing requirements on reduction of footprint, power dissipation and cost, as well as increased bandwidth. Nanophotonics integrated photonics has been viewed as a solution to this, capitalizing on development in nanotechnology and an increased understanding of light matter interaction on the nanoscale. The latter can be exemplified by plasmonics and low dimensional semiconductors such as quantum dots (QDs). In this scenario the development of improved electrooptic materials is of great importance, the electrooptic polymers being an example, since they potentially offer superior properties for optical phase modulators in terms of power and integratability. Phase modulators are essential for e.g. the rapidly developing advanced modulation formats, since phase modulation basically can generate any type of modulation. The electrooptic polymers, in combination with plasmonics nanoparticle array waveguides or nanostructured hybrid plasmonic media can give extremely compact and low power dissipation modulators. Low-dimensional semiconductors, e.g. in the shape of QDs, can be employed for modulation or switching functions, offering possibilities for scaling to 2 or 3 dimensions for advanced switching functions. In both the high field confinement plasmonics and QDs, the nanosizing is due to nearfield interactions, albeit being of different physical origin in the two cases. Epitaxial integration of III-V structures on Si plays an important role in developing high-performance light sources on silicon, eventually integrated with silicon electronics. A brief remark on all-optical vs. electronically controlled optical switching systems is also given.
NASA Astrophysics Data System (ADS)
1992-05-01
The function of the Space Station Furnace Facility (SSFF) is to support materials research into the crystal growth and solidification processes of electronic and photonic materials, metals and alloys, and glasses and ceramics. To support this broad base of research requirements, the SSFF will employ a variety of furnace modules which will be operated, regulated, and supported by a core of common subsystems. Furnace modules may be reconfigured or specifically developed to provide unique solidification conditions for each set of experiments. The SSFF modular approach permits the addition of new or scaled-up furnace modules to support the evolution of the facility as new science requirements are identified. The SSFF Core is of modular design to permit augmentation for enhanced capabilities. The fully integrated configuration of the SSFF will consist of three racks with the capability of supporting up to two furnace modules per rack. The initial configuration of the SSFF will consist of two of the three racks and one furnace module. This Experiment/Facility Requirements Document (E/FRD) describes the integrated facility requirements for the Space Station Freedom (SSF) Integrated Configuration-1 (IC1) mission. The IC1 SSFF will consist of two racks: the Core Rack, with the centralized subsystem equipment; and the Experiment Rack-1, with Furnace Module-1 and the distributed subsystem equipment to support the furnace. The SSFF support functions are provided by the following Core subsystems: power conditioning and distribution subsystem (SSFF PCDS); data management subsystem (SSFF DMS); thermal control Subsystem (SSFF TCS); gas distribution subsystem (SSFF GDS); and mechanical structures subsystem (SSFF MSS).
NASA Technical Reports Server (NTRS)
1992-01-01
The function of the Space Station Furnace Facility (SSFF) is to support materials research into the crystal growth and solidification processes of electronic and photonic materials, metals and alloys, and glasses and ceramics. To support this broad base of research requirements, the SSFF will employ a variety of furnace modules which will be operated, regulated, and supported by a core of common subsystems. Furnace modules may be reconfigured or specifically developed to provide unique solidification conditions for each set of experiments. The SSFF modular approach permits the addition of new or scaled-up furnace modules to support the evolution of the facility as new science requirements are identified. The SSFF Core is of modular design to permit augmentation for enhanced capabilities. The fully integrated configuration of the SSFF will consist of three racks with the capability of supporting up to two furnace modules per rack. The initial configuration of the SSFF will consist of two of the three racks and one furnace module. This Experiment/Facility Requirements Document (E/FRD) describes the integrated facility requirements for the Space Station Freedom (SSF) Integrated Configuration-1 (IC1) mission. The IC1 SSFF will consist of two racks: the Core Rack, with the centralized subsystem equipment; and the Experiment Rack-1, with Furnace Module-1 and the distributed subsystem equipment to support the furnace. The SSFF support functions are provided by the following Core subsystems: power conditioning and distribution subsystem (SSFF PCDS); data management subsystem (SSFF DMS); thermal control Subsystem (SSFF TCS); gas distribution subsystem (SSFF GDS); and mechanical structures subsystem (SSFF MSS).
McLean, Michelle; Murrell, Kathy
2002-03-01
WebCT, front-end software for Internet-delivered material, became an integral part of a problem-based learning, student-centred curriculum introduced in January 2001 at the Nelson R. Mandela School of Medicine (South Africa). A template for six curriculum and two supplementary modules was developed. Organiser and Tool pages were added and files uploaded as each module progressed. This study provides feedback from students with regard to the value of WebCT in their curriculum, as well as discussing the value of WebCT for the delivery of digitized material (e.g., images, videos, PowerPoint presentations). In an anonymous survey following the completion of the first module, students, apparently irrespective of their level of computer literacy, responded positively to the communication facility between staff and students and amongst students, the resources and the URLs. Based on these preliminary responses, WebCT courses for all six modules were developed during 2001. With Faculty support, WebCT will probably be integrated into the rest of the MBChB programme. It will be particularly useful when students are off campus, undertaking electives and community service in the later years.
NASA Astrophysics Data System (ADS)
Holmes, Mark H.
2006-10-01
To help students grasp the intimate connections that exist between mathematics and its applications in other disciplines a library of interactive learning modules was developed. This library covers the mathematical areas normally studied by undergraduate students and is used in science courses at all levels. Moreover, the library is designed not just to provide critical connections across disciplines but to also provide longitudinal subject reinforcement as students progress in their studies. In the process of developing the modules a complete editing and publishing system was constructed that is optimized for automated maintenance and upgradeability of materials. The result is a single integrated production system for web-based educational materials. Included in this is a rigorous assessment program, involving both internal and external evaluations of each module. As will be seen, the formative evaluation obtained during the development of the library resulted in the modules successfully bridging multiple disciplines and breaking down the disciplinary barriers commonly found in their math and non-math courses.
NASA Astrophysics Data System (ADS)
Walker, B.; Fadem, C. M.; Shellito, L. J.
2014-12-01
Designing climate change curricular materials suitable for wide adoption across institutions and academic disciplines (including those outside of the geosciences) requires collaboration among faculty at different types of institutions and consideration of a variety of student populations, learning styles, and course formats. The Interdisciplinary Teaching of Geoscience for a Sustainable Future (InTeGrate) project, an NSF STEP Center program, provides opportunities for faculty to develop 2-3 week teaching modules to engage students in understanding the intersections between geoscience topics and societal issues. From 2012-2014, a team of 3 faculty from a liberal arts college, comprehensive university, and community college developed, implemented, assessed, and revised a 2-3 week module for introductory undergraduates entitled "Climate of change: interactions and feedbacks between water, air, and ice". The module uses authentic atmosphere, ocean, and cryosphere data from several regions to illustrate how climate impacts human societies and that the climate system has interacting components complicated by feedbacks, uncertainties, and human behavioral decisions. Students also consider past and present human adaptations to climate fluctuations. The module was piloted in introductory geology, meteorology, and oceanography courses during the 2012-2013 academic year, during which time formative and summative assessments were administered and used to modify the curricular materials. We will provide an overview of the module's content, instructional strategies involved in implementing the module, and methods of formative and summative assessment. We will also report on lessons learned during the development, piloting, revision, and publishing process, the importance of fostering partnerships between faculty from different institution types, and design approaches that promote widespread adoption of climate curricular materials.
NASA Astrophysics Data System (ADS)
Onea, A.; Hering, W.; Reiser, J.; Weisenburger, A.; Diez de los Rios Ramos, N.; Lux, M.; Ziegler, R.; Baumgärtner, S.; Stieglitz, R.
2017-07-01
Three classes of experimental liquid metal facilities have been completed during the LIMTECH project aiming the qualification of materials, investigation of thermoelectrical modules, investigation of sodium transitional regimes and fundamental thermo-dynamical flows in concentrating solar power (CSP) relevant geometries. ATEFA facility is dedicated to basic science investigation focussed on the alkali metal thermal-to-electric converter (AMTEC) technology. Three SOLTEC facilities are aimed to be used in different laboratories for long term material investigation sodium environment up to a 1000 K temperature and for long term tests of AMTEC modules. The medium scale integral facility KASOLA is planned as the backbone for CSP development and demonstration.
Passive and electro-optic polymer photonics and InP electronics integration
NASA Astrophysics Data System (ADS)
Zhang, Z.; Katopodis, V.; Groumas, P.; Konczykowska, A.; Dupuy, J.-.; Beretta, A.; Dede, A.; Miller, E.; Choi, J. H.; Harati, P.; Jorge, F.; Nodjiadjim, V.; Dinu, R.; Cangini, G.; Vannucci, A.; Felipe, D.; Maese-Novo, A.; Keil, N.; Bach, H.-.; Schell, Martin; Avramopoulos, H.; Kouloumentas, Ch.
2015-05-01
Hybrid photonic integration allows individual components to be developed at their best-suited material platforms without sacrificing the overall performance. In the past few years a polymer-enabled hybrid integration platform has been established, comprising 1) EO polymers for constructing low-complexity and low-cost Mach-Zehnder modulators (MZMs) with extremely high modulation bandwidth; 2) InP components for light sources, detectors, and high-speed electronics including MUX drivers and DEMUX circuits; 3) Ceramic (AIN) RF board that links the electronic signals within the package. On this platform, advanced optoelectronic modules have been demonstrated, including serial 100 Gb/s [1] and 2x100 Gb/s [2] optical transmitters, but also 400 Gb/s optoelectronic interfaces for intra-data center networks [3]. To expand the device functionalities to an unprecedented level and at the same time improve the integration compatibility with diversified active / passive photonic components, we have added a passive polymer-based photonic board (polyboard) as the 4th material system. This passive polyboard allows for low-cost fabrication of single-mode waveguide networks, enables fast and convenient integration of various thin-film elements (TFEs) to control the light polarization, and provides efficient thermo-optic elements (TOEs) for wavelength tuning, light amplitude regulation and light-path switching.
Quartz/fused silica chip carriers
NASA Technical Reports Server (NTRS)
1992-01-01
The primary objective of this research and development effort was to develop monolithic microwave integrated circuit (MMIC) packaging which will operate efficiently at millimeter-wave frequencies. The packages incorporated fused silica as the substrate material which was selected due to its favorable electrical properties and potential performance improvement over more conventional materials for Ka-band operation. The first step towards meeting this objective is to develop a package that meets standard mechanical and thermal requirements using fused silica and to be compatible with semiconductor devices operating up to at least 44 GHz. The second step is to modify the package design and add multilayer and multicavity capacity to allow for application specific integrated circuits (ASIC's) to control multiple phase shifters. The final step is to adapt the package design to a phased array module with integral radiating elements. The first task was a continuation of the SBIR Phase 1 work. Phase 1 identified fused silica as a viable substrate material by demonstrating various plating, machining, and adhesion properties. In Phase 2 Task 1, a package was designed and fabricated to validate these findings. Task 2 was to take the next step in packaging and fabricate a multilayer, multichip module (MCM). This package is the predecessor to the phased array module and demonstrates the ability to via fill, circuit print, laminate, and to form vertical interconnects. The final task was to build a phased array module. The radiating elements were to be incorporated into the package instead of connecting to it with wire or ribbon bonds.
Analytical Design Package (ADP2): A computer aided engineering tool for aircraft transparency design
NASA Technical Reports Server (NTRS)
Wuerer, J. E.; Gran, M.; Held, T. W.
1994-01-01
The Analytical Design Package (ADP2) is being developed as a part of the Air Force Frameless Transparency Program (FTP). ADP2 is an integrated design tool consisting of existing analysis codes and Computer Aided Engineering (CAE) software. The objective of the ADP2 is to develop and confirm an integrated design methodology for frameless transparencies, related aircraft interfaces, and their corresponding tooling. The application of this methodology will generate high confidence for achieving a qualified part prior to mold fabrication. ADP2 is a customized integration of analysis codes, CAE software, and material databases. The primary CAE integration tool for the ADP2 is P3/PATRAN, a commercial-off-the-shelf (COTS) software tool. The open architecture of P3/PATRAN allows customized installations with different applications modules for specific site requirements. Integration of material databases allows the engineer to select a material, and those material properties are automatically called into the relevant analysis code. The ADP2 materials database will be composed of four independent schemas: CAE Design, Processing, Testing, and Logistics Support. The design of ADP2 places major emphasis on the seamless integration of CAE and analysis modules with a single intuitive graphical interface. This tool is being designed to serve and be used by an entire project team, i.e., analysts, designers, materials experts, and managers. The final version of the software will be delivered to the Air Force in Jan. 1994. The Analytical Design Package (ADP2) will then be ready for transfer to industry. The package will be capable of a wide range of design and manufacturing applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
JENNINGS, T.L.
The Work Flow analysis Report will be used to facilitate the requirements for implementing the Work Control module of Passport. The report consists of workflow integration processes for Work Management, Preventative Maintenance, Materials and Equipment
Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion
NASA Astrophysics Data System (ADS)
1984-06-01
Research on electric motor vehicles is reported in the areas of active material utilization and active material integrity; design and fabrication of components, advanced cells, and modules; cell testing; and battery thermal management and electrolyte circulation subsystems.
R&D issues in scale-up and manufacturing of amorphous silicon tandem modules
NASA Astrophysics Data System (ADS)
Arya, R. R.; Carlson, D. E.; Chen, L. F.; Ganguly, G.; He, M.; Lin, G.; Middya, R.; Wood, G.; Newton, J.; Bennett, M.; Jackson, F.; Willing, F.
1999-03-01
R & D on amorphous silicon based tandem junction devices has improved the throughtput, the material utilization, and the performance of devices on commercial tin oxide coated glass. The tandem junction technology has been scaled-up to produce 8.6 Ft2 monolithically integrated modules in manufacturing at the TF1 plant. Optimization of performance and stability of these modules is ongoing.
[Development of a French-language online health policy course: an international collaboration].
Hébert, Réjean; Coppieters, Yves; Pradier, Christian; Williams-Jones, Bryn; Brahimi, Cora; Farley, Céline
2017-01-01
To present the process and challenges of developing an online competency-based course on public health policy using a collaborative international approach. Five public health experts, supported by an expert in educational technology, adopted a rigorous approach to the development of the course: a needs analysis, identification of objectives and competencies, development of a pedagogical scenario for each module and target, choice of teaching methods and learning activities, material to be identified or developed, and the responsibilities and tasks involved. The 2-credit (90-hour) graduate course consists of six modules including an integration module. The modules start with a variety of case studies: tobacco law (neutral packaging), supervised injection sites, housing, integrated services for the frail elderly, a prevention programme for mothers from disadvantaged backgrounds, and the obligatory use of bicycle helmets. In modules 1, 3, 4 and 5, students learn about different stages of the public policy development process: emergence, formulation and adoption, implementation and evaluation. Module 2 focuses on the importance of values and ideologies in public policy. The integration module allows the students to apply the knowledge learned and addresses the role of experts in public policy and ethical considerations. The course has been integrated into the graduate programmes of the participating universities and allows students to follow, at a distance, an innovative training programme.
NASA Astrophysics Data System (ADS)
Doser, D. I.; Villalobos, J. I.; Henry, I. E.
2014-12-01
InTeGrate (Interdisciplinary Teaching about Earth for a Sustainable Future) has developed teaching modules that focus on Earth sustainability and Earth-centered societal issues. We have begun to implement modules on climate change, earth materials and freshwater into introductory geology and environmental science courses taught at the University of Texas at El Paso (UTEP), El Paso Community College (EPCC) and local early college high schools (ECHS) for classes of 20 to 220 students. Our eventual goal is to insure students taking introductory classes at any institution will be exposed to comparable content and be similarly prepared for advanced courses. Our initial results suggest that the modules' use of case studies and analysis of authentic data sets are very appealing to our student body (over 70% Hispanic). Since many students do not speak English at home, they were challenged by vocabulary presented in some modules. Modules containing glossaries and extensive background material (such as concept maps and annotated figures) proved very helpful to these students. The use of pre-activity quizzes insured that the students had mastered basic concepts needed for in-class activities. Modifications required to teach these modules in larger classes included condensing materials and reducing the amount of color figures to save paper and printer costs, streamlining dissemination/collection of in-class group assignments, and adapting assignments such as jigsaws and gallery walks to the confines of a large lecture hall with fixed seating. Student reflections indicated students were able to make connections to societal issues and retain these ideas through the end of the courses.
Low-power silicon-organic hybrid (SOH) modulators for advanced modulation formats.
Lauermann, M; Palmer, R; Koeber, S; Schindler, P C; Korn, D; Wahlbrink, T; Bolten, J; Waldow, M; Elder, D L; Dalton, L R; Leuthold, J; Freude, W; Koos, C
2014-12-01
We demonstrate silicon-organic hybrid (SOH) electro-optic modulators that enable quadrature phase-shift keying (QPSK) and 16-state quadrature amplitude modulation (16QAM) with high signal quality and record-low energy consumption. SOH integration combines highly efficient electro-optic organic materials with conventional silicon-on-insulator (SOI) slot waveguides, and allows to overcome the intrinsic limitations of silicon as an optical integration platform. We demonstrate QPSK and 16QAM signaling at symbol rates of 28 GBd with peak-to-peak drive voltages of 0.6 V(pp). For the 16QAM experiment at 112 Gbit/s, we measure a bit-error ratio of 5.1 × 10⁻⁵ and a record-low energy consumption of only 19 fJ/bit.
NASA Astrophysics Data System (ADS)
Mrejen, Michael; Suchowski, Haim; Bachelard, Nicolas; Wang, Yuan; Zhang, Xiang
2017-07-01
High-speed Silicon Photonics calls for solutions providing a small footprint, high density, and minimum crosstalk, as exemplified by the recent development of integrated optical modulators. Yet, the performances of such modulators are hindered by intrinsic material losses, which results in low energy efficiency. Using the concept of Adiabatic Elimination, here, we introduce a scheme allowing for the low-loss modulation in densely packed waveguides. Our system is composed of two waveguides, whose coupling is mediated by an intermediate third waveguide. The signal is carried by the two outer modes, while the active control of their coupling is achieved via the intermediate dark mode. The modulation is performed by the manipulation of the central-waveguide mode index, leaving the signal-carrying waveguides unaffected by the loss. We discuss how Adiabatic Elimination provides a solution for mitigating signal losses and designing relatively compact, broadband, and energy-efficient integrated optical modulators.
Ten Years in the Academic Integrity Trenches: Experiences and Issues
ERIC Educational Resources Information Center
Atkinson, Doug; Nau, S. Zaung; Symons, Christine
2016-01-01
In 2016, our university launched its Academic Integrity Program (AIP) in order to promote and protect academic integrity. All commencing students must complete this online AIP within 14 days of starting their course. Satisfactory completion of this module with a test score of 80% is required before students can access their course materials.…
Structural reliability methods: Code development status
NASA Astrophysics Data System (ADS)
Millwater, Harry R.; Thacker, Ben H.; Wu, Y.-T.; Cruse, T. A.
1991-05-01
The Probabilistic Structures Analysis Method (PSAM) program integrates state of the art probabilistic algorithms with structural analysis methods in order to quantify the behavior of Space Shuttle Main Engine structures subject to uncertain loadings, boundary conditions, material parameters, and geometric conditions. An advanced, efficient probabilistic structural analysis software program, NESSUS (Numerical Evaluation of Stochastic Structures Under Stress) was developed as a deliverable. NESSUS contains a number of integrated software components to perform probabilistic analysis of complex structures. A nonlinear finite element module NESSUS/FEM is used to model the structure and obtain structural sensitivities. Some of the capabilities of NESSUS/FEM are shown. A Fast Probability Integration module NESSUS/FPI estimates the probability given the structural sensitivities. A driver module, PFEM, couples the FEM and FPI. NESSUS, version 5.0, addresses component reliability, resistance, and risk.
Structural reliability methods: Code development status
NASA Technical Reports Server (NTRS)
Millwater, Harry R.; Thacker, Ben H.; Wu, Y.-T.; Cruse, T. A.
1991-01-01
The Probabilistic Structures Analysis Method (PSAM) program integrates state of the art probabilistic algorithms with structural analysis methods in order to quantify the behavior of Space Shuttle Main Engine structures subject to uncertain loadings, boundary conditions, material parameters, and geometric conditions. An advanced, efficient probabilistic structural analysis software program, NESSUS (Numerical Evaluation of Stochastic Structures Under Stress) was developed as a deliverable. NESSUS contains a number of integrated software components to perform probabilistic analysis of complex structures. A nonlinear finite element module NESSUS/FEM is used to model the structure and obtain structural sensitivities. Some of the capabilities of NESSUS/FEM are shown. A Fast Probability Integration module NESSUS/FPI estimates the probability given the structural sensitivities. A driver module, PFEM, couples the FEM and FPI. NESSUS, version 5.0, addresses component reliability, resistance, and risk.
NASA Technical Reports Server (NTRS)
Hoffman, James Patrick; Del Castillo, Linda; Miller, Jennifer; Jenabi, Masud; Hunter, Donald; Birur, Gajanana
2011-01-01
The higher output power densities required of modern radar architectures, such as the proposed DESDynI [Deformation, Ecosystem Structure, and Dynamics of Ice] SAR [Synthetic Aperture Radar] Instrument (or DSI) require increasingly dense high power electronics. To enable these higher power densities, while maintaining or even improving hardware reliability, requires advances in integrating advanced thermal packaging technologies into radar transmit/receive (TR) modules. New materials and techniques have been studied and compared to standard technologies.
Diversity and Periodicity: An Inorganic Chemistry Module. Teacher's Guide.
ERIC Educational Resources Information Center
Huheey, James; Sandoval, Amado
This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching inorganic chemistry. The material in this book can be integrated with the other modules in a sequence that helps students to see that chemistry is a unified science. Contents include: (1) "Periodicity: A Chemical Calendar"; (2)…
Communities of Molecules: A Physical Chemistry Module. Teacher's Guide.
ERIC Educational Resources Information Center
DeVoe, Howard; Hearle, Robert
This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching physical chemistry. The material in this book can be integrated with the other modules in a sequence that helps students see that chemistry is a unified science. Contents include: (1) "Introduction of Physical Chemistry"; (2) "The…
Infusing Alcohol and Drug Prevention with Existing Classroom Study Units: Health.
ERIC Educational Resources Information Center
Valencia Community Coll., Orlando, FL.
This curriculum module, one of seven in Infusion Project, offers information and lessons on drug use prevention for integration into an existing seventh grade middle school health curriculum. The module, based on a type of interactive learning called infusion learning, contains 10 lessons each providing objectives, a list of resource materials,…
System design of the Pioneer Venus spacecraft. Volume 5: Probe vehicle studies
NASA Technical Reports Server (NTRS)
Nolte, L. J.; Stephenson, D. S.
1973-01-01
A summary of the key issues and studies conducted for the Pioneer Venus spacecraft and the resulting probe designs are presented. The key deceleration module issues are aerodynamic configuration and heat shield material selection. The design and development of the pressure vessel module are explained. Thermal control and science integration of the pressure vessel module are explained. The deceleration module heat shield, parachute and separation/despin are reported. The Thor/Delta and Atlas/Centaur baseline descriptions are provided.
Modular microfluidic systems using reversibly attached PDMS fluid control modules
NASA Astrophysics Data System (ADS)
Skafte-Pedersen, Peder; Sip, Christopher G.; Folch, Albert; Dufva, Martin
2013-05-01
The use of soft lithography-based poly(dimethylsiloxane) (PDMS) valve systems is the dominating approach for high-density microscale fluidic control. Integrated systems enable complex flow control and large-scale integration, but lack modularity. In contrast, modular systems are attractive alternatives to integration because they can be tailored for different applications piecewise and without redesigning every element of the system. We present a method for reversibly coupling hard materials to soft lithography defined systems through self-aligning O-ring features thereby enabling easy interfacing of complex-valve-based systems with simpler detachable units. Using this scheme, we demonstrate the seamless interfacing of a PDMS-based fluid control module with hard polymer chips. In our system, 32 self-aligning O-ring features protruding from the PDMS fluid control module form chip-to-control module interconnections which are sealed by tightening four screws. The interconnection method is robust and supports complex fluidic operations in the reversibly attached passive chip. In addition, we developed a double-sided molding method for fabricating PDMS devices with integrated through-holes. The versatile system facilitates a wide range of applications due to the modular approach, where application specific passive chips can be readily attached to the flow control module.
Neutronic calculation of fast reactors by the EUCLID/V1 integrated code
NASA Astrophysics Data System (ADS)
Koltashev, D. A.; Stakhanova, A. A.
2017-01-01
This article considers neutronic calculation of a fast-neutron lead-cooled reactor BREST-OD-300 by the EUCLID/V1 integrated code. The main goal of development and application of integrated codes is a nuclear power plant safety justification. EUCLID/V1 is integrated code designed for coupled neutronics, thermomechanical and thermohydraulic fast reactor calculations under normal and abnormal operating conditions. EUCLID/V1 code is being developed in the Nuclear Safety Institute of the Russian Academy of Sciences. The integrated code has a modular structure and consists of three main modules: thermohydraulic module HYDRA-IBRAE/LM/V1, thermomechanical module BERKUT and neutronic module DN3D. In addition, the integrated code includes databases with fuel, coolant and structural materials properties. Neutronic module DN3D provides full-scale simulation of neutronic processes in fast reactors. Heat sources distribution, control rods movement, reactivity level changes and other processes can be simulated. Neutron transport equation in multigroup diffusion approximation is solved. This paper contains some calculations implemented as a part of EUCLID/V1 code validation. A fast-neutron lead-cooled reactor BREST-OD-300 transient simulation (fuel assembly floating, decompression of passive feedback system channel) and cross-validation with MCU-FR code results are presented in this paper. The calculations demonstrate EUCLID/V1 code application for BREST-OD-300 simulating and safety justification.
Advanced Soldier Thermoelectric Power System for Power Generation from Battlefield Heat Sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hendricks, Terry J.; Hogan, Tim; Case, Eldon D.
2010-09-01
The U.S. military uses large amounts of fuel during deployments and battlefield operations. This project sought to develop a lightweight, small form-factor, soldier-portable advanced thermoelectric (TE) system prototype to recover and convert waste heat from various deployed military equipment (i.e., diesel generators/engines, incinerators, vehicles, and potentially mobile kitchens), with the ultimate purpose of producing power for soldier battery charging, advanced capacitor charging, and other battlefield power applications. The technical approach employed microchannel technology, a unique “power panel” approach to heat exchange/TE system integration, and newly-characterized LAST (lead-antimony-silver-telluride) and LASTT (lead-antimony-silver-tin-telluride) TE materials segmented with bismuth telluride TE materials in designingmore » a segmented-element TE power module and system. This project researched never-before-addressed system integration challenges (thermal expansion, thermal diffusion, electrical interconnection, thermal and electrical interfaces) of designing thin “power panels” consisting of alternating layers of thin, microchannel heat exchangers (hot and cold) sandwiching thin, segmented-element TE power generators. The TE properties, structurally properties, and thermal fatigue behavior of LAST and LASTT materials were developed and characterized such that the first segmented-element TE modules using LAST / LASTT materials were fabricated and tested at hot-side temperatures = 400 °C and cold-side temperatures = 40 °C. LAST / LASTT materials were successfully segmented with bismuth telluride and electrically interconnected with diffusion barrier materials and copper strapping within the module electrical circuit. A TE system design was developed to produce 1.5-1.6 kW of electrical energy using these new TE modules from the exhaust waste heat of 60-kW Tactical Quiet Generators as demonstration vehicles.« less
Integrating Phase-Change Materials into Automotive Thermoelectric Generators
NASA Astrophysics Data System (ADS)
Klein Altstedde, Mirko; Rinderknecht, Frank; Friedrich, Horst
2014-06-01
Because the heat emitted by conventional combustion-engine vehicles during operation has highly transient properties, automotive thermoelectric generators (TEG) are intended for a particular operating state (design point). This, however, leads to two problems. First, whenever the combustion engine runs at low load, the maximum operating temperature cannot be properly utilised; second, a combustion engine at high load requires partial diversion of exhaust gas away from the TEG to protect the thermoelectric modules. An attractive means of stabilising dynamic exhaust behaviour (thereby keeping the TEG operating status at the design point for as long as possible) is use of latent heat storage, also known as phase-change materials (PCM). By positioning PCM between module and exhaust heat conduit, and choosing a material with a phase-change temperature matching the module's optimum operating temperature, it can be used as heat storage. This paper presents results obtained during examination of the effect of integration of latent heat storage on the potential of automotive TEG to convert exhaust heat. The research resulted in the development of a concept based on the initial integration idea, followed by proof of concept by use of a specially created prototype. In addition, the potential amount of energy obtained by use of a PCM-equipped TEG was calculated. The simulations indicated a significant increase in electrical energy was obtained in the selected test cycle.
R&D issues in scale-up and manufacturing of amorphous silicon tandem modules
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arya, R.R.; Carlson, D.E.; Chen, L.F.
1999-03-01
R & D on amorphous silicon based tandem junction devices has improved the throughtput, the material utilization, and the performance of devices on commercial tin oxide coated glass. The tandem junction technology has been scaled-up to produce 8.6&hthinsp;Ft{sup 2} monolithically integrated modules in manufacturing at the TF1 plant. Optimization of performance and stability of these modules is ongoing. {copyright} {ital 1999 American Institute of Physics.}
The Heart of Matter: A Nuclear Chemistry Module. Teacher's Guide.
ERIC Educational Resources Information Center
Viola, Vic; Hearle, Robert
This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching nuclear chemistry. In this book, the fundamental concepts of nuclear science and the applications of nuclear energy are discussed. The material in this book can be integrated with the other modules in a sequence that helps students…
UMAP Modules-Units 203-211, 215-216, 231-232.
ERIC Educational Resources Information Center
Schoenfeld, Alan H.; And Others
One module is presented in units 203, 204, and 205, as a guide for students, and presents a general strategy for solving integrals effectively. With this material is a solutions manual to exercises. This document set also includes a unit featuring applications of calculus to geography: 206-Mercator's World Map and the Calculus. Unit 207-Management…
Study program for encapsulation materials interface for low-cost solar array
NASA Technical Reports Server (NTRS)
Kaelble, D. H.; Mansfeld, F. B.; Kendig, M.; Leung, C.
1981-01-01
The service integrity of the bonded interface in solar cell modules used in solar arrays is addressed. The development of AC impedance as a nondestructive evaluation (NDE) methodology for solar arrays is reported along with development of corrosion models and materials selection criteria for corrosion resistant interfaces.
Propulsion/flight control integration technology (PROFIT) software system definition
NASA Technical Reports Server (NTRS)
Carlin, C. M.; Hastings, W. J.
1978-01-01
The Propulsion Flight Control Integration Technology (PROFIT) program is designed to develop a flying testbed dedicated to controls research. The control software for PROFIT is defined. Maximum flexibility, needed for long term use of the flight facility, is achieved through a modular design. The Host program, processes inputs from the telemetry uplink, aircraft central computer, cockpit computer control and plant sensors to form an input data base for use by the control algorithms. The control algorithms, programmed as application modules, process the input data to generate an output data base. The Host program formats the data for output to the telemetry downlink, the cockpit computer control, and the control effectors. Two applications modules are defined - the bill of materials F-100 engine control and the bill of materials F-15 inlet control.
Murphy, Cynthia F; Kenig, George A; Allen, David T; Laurent, Jean-Philippe; Dyer, David E
2003-12-01
Currently available data suggest that most of the energy and material consumption related to the production of an integrated circuit is due to the wafer fabrication process. The complexity of wafer manufacturing, requiring hundreds of steps that vary from product to product and from facility to facility and which change every few years, has discouraged the development of material, energy, and emission inventory modules for the purpose of insertion into life cycle assessments. To address this difficulty, a flexible, process-based system for estimating material requirements, energy requirements, and emissions in wafer fabrication has been developed. The method accounts for mass and energy use atthe unit operation level. Parametric unit operation modules have been developed that can be used to predict changes in inventory as the result of changes in product design, equipment selection, or process flow. A case study of the application of the modules is given for energy consumption, but a similar methodology can be used for materials, individually or aggregated.
NASA Astrophysics Data System (ADS)
Geary, Kevin
The development of high-frequency polymer electro-optic modulators has seen steady and significant progress in recent years, yet applications of these promising materials to more complicated integrated optic structures and arrays of devices have been limited primarily due to high optical waveguide loss characteristics. This is unfortunate since a major advantage of polymers as photonic materials is their compatibility with photolithographic processing of large components. In this Dissertation, etchless waveguide writing techniques are presented in order to improve the overall optical insertion loss of electro-optic polymer waveguide devices. These techniques include poling-induced writing, stress-induced waveguide writing, and photobleaching. Using these waveguide writing mechanisms, we have demonstrated straight waveguides, phase modulators, Mach-Zehnder intensity modulators, variable optical attenuators, and multimode interference (MMI) power splitters, all with improved loss characteristics over their etched rib waveguide counterparts. Ultimately, the insertion loss of an integrated optic device is limited by the actual material loss of the core waveguide material. In this Dissertation, passive-to-active polymer waveguide transitions are proposed to circumvent this problem. These transitions are compact, in-plane, self-aligned, and require no tapering of any physical dimensions of the waveguides. By utilizing both the time-dependent and intensity-dependent photobleaching characteristics of electro-optic polymer materials, adiabatic refractive index tapers can be seamlessly coupled to in-plane butt couple transitions, resulting in losses as low as 0.1 dB per interface. By integrating passive polymer planar lightwave circuits with the high-speed phase shifting capability of electro-optic polymers, active wideband photonic devices of increased size and complexity can be realized. Optical fiber-to-device coupling can also result in significant contributions to the overall insertion loss of an integrated electro-optic polymer device. In this Dissertation, we leverage the photobleached refractive index taper component of our proposed passive-to-active polymer waveguide transitions in order to realize a two-dimensional optical mode transformer for improved overall fiber-to-device coupling of electro-optic polymer waveguide devices.
Optical design for reliability and efficiency in concentrating photovoltaics
NASA Astrophysics Data System (ADS)
Leutz, Ralf; Annen, Hans Philipp; Fu, Ling
2010-08-01
Complex systems like modules in concentrating photovoltaics (CPV) are designed in a systems approach. The better the components are concerted, the better the performance goals of the system can be fulfilled. Optics are central to the CPV module's reliability and efficiency. Fresnel lens optics provide the module cover, and protect the module against the environment. Fresnel lenses on glass can provide the module's structural integrity. The secondary optical element, used to increase the collection of light, the acceptance half-angle, and the uniformity on the cell, may provide encapsulation for the receiver. This encapsulation function may be provided by some optical designs in sol gel, or silicone. Both materials are unknown in their longevity in this application. We present optical designs fulfilling structural or protective functions, discuss the optical penalties to be paid, and the innovative materials and manufacturing technologies to be tested.
Glogowska, Margaret; Young, Pat; Lockyer, Lesley; Moule, Pam
2011-11-01
This paper explores students' perceptions of blended learning modules delivered in a Continuing Professional Development (CPD) health care context in the UK. 'Blended learning' is the term used to describe a hybrid model of learning where traditional face-to-face teaching approaches and newer electronic learning activities and resources are utilised together. A new model of CPD for health care practitioners based on a blended learning approach was developed at a university in the south west of England. As part of the evaluation of the new modules, a qualitative study was conducted, in which 17 students who had experienced the modules were interviewed by telephone. Three main themes emerged from the interviews relating to the 'blended' nature of the blended learning modules. These were i) issues around the opportunities for discussion of online materials face-to-face; ii) issues of what material should be online versus face-to-face and iii) balancing online and face-to-face components. Teaching staff engaged in the development of blended learning courses need to pay particular attention to the ways in which they develop and integrate online and face-to-face materials. More attention needs to be paid to allowing opportunity for students to come together to create a 'community of inquiry'. Copyright © 2011 Elsevier Ltd. All rights reserved.
PRiME: integrating professional responsibility into the engineering curriculum.
Moore, Christy; Hart, Hillary; Randall, D'Arcy; Nichols, Steven P
2006-04-01
Engineering educators have long discussed the need to teach professional responsibility and the social context of engineering without adding to overcrowded curricula. One difficulty we face is the lack of appropriate teaching materials that can fit into existing courses. The PRiME (Professional Responsibility Modules for Engineering) Project (http://www.engr.utexas.edu/ethics/primeModules.cfm) described in this paper was initiated at the University of Texas, Austin to provide web-based modules that could be integrated into any undergraduate engineering class. Using HPL (How People Learn) theory, PRiME developed and piloted four modules during the academic year 2004-2005. This article introduces the modules and the pilot, outlines the assessment process, analyzes the results, and describes how the modules are being revised in light of the initial assessment. In its first year of development and testing, PRiME made significant progress towards meeting its objectives. The PRiME Project can strengthen engineering education by providing faculty with an effective system for engaging students in learning about professional responsibility.
NASA Astrophysics Data System (ADS)
Hasan, Mehedi; Hu, Jianqi; Nikkhah, Hamdam; Hall, Trevor
2017-08-01
A novel photonic integrated circuit architecture for implementing orthogonal frequency division multiplexing by means of photonic generation of phase-correlated sub-carriers is proposed. The circuit can also be used for implementing complex modulation, frequency up-conversion of the electrical signal to the optical domain and frequency multiplication. The principles of operation of the circuit are expounded using transmission matrices and the predictions of the analysis are verified by computer simulation using an industry-standard software tool. Non-ideal scenarios that may affect the correct function of the circuit are taken into consideration and quantified. The discussion of integration feasibility is illustrated by a photonic integrated circuit that has been fabricated using 'library' components and which features most of the elements of the proposed circuit architecture. The circuit is found to be practical and may be fabricated in any material platform that offers a linear electro-optic modulator such as organic or ferroelectric thin films hybridized with silicon photonics.
Scaling vectors of attoJoule per bit modulators
NASA Astrophysics Data System (ADS)
Sorger, Volker J.; Amin, Rubab; Khurgin, Jacob B.; Ma, Zhizhen; Dalir, Hamed; Khan, Sikandar
2018-01-01
Electro-optic modulation performs the conversion between the electrical and optical domain with applications in data communication for optical interconnects, but also for novel optical computing algorithms such as providing nonlinearity at the output stage of optical perceptrons in neuromorphic analog optical computing. While resembling an optical transistor, the weak light-matter-interaction makes modulators 105 times larger compared to their electronic counterparts. Since the clock frequency for photonics on-chip has a power-overhead sweet-spot around tens of GHz, ultrafast modulation may only be required in long-distance communication, not for short on-chip links. Hence, the search is open for power-efficient on-chip modulators beyond the solutions offered by foundries to date. Here, we show scaling vectors towards atto-Joule per bit efficient modulators on-chip as well as some experimental demonstrations of novel plasmonic modulators with sub-fJ/bit efficiencies. Our parametric study of placing different actively modulated materials into plasmonic versus photonic optical modes shows that 2D materials overcompensate their miniscule modal overlap by their unity-high index change. Furthermore, we reveal that the metal used in plasmonic-based modulators not only serves as an electrical contact, but also enables low electrical series resistances leading to near-ideal capacitors. We then discuss the first experimental demonstration of a photon-plasmon-hybrid graphene-based electro-absorption modulator on silicon. The device shows a sub-1 V steep switching enabled by near-ideal electrostatics delivering a high 0.05 dB V-1 μm-1 performance requiring only 110 aJ/bit. Improving on this demonstration, we discuss a plasmonic slot-based graphene modulator design, where the polarization of the plasmonic mode aligns with graphene’s in-plane dimension; where a push-pull dual-gating scheme enables 2 dB V-1 μm-1 efficient modulation allowing the device to be just 770 nm short for 3 dB small signal modulation. Lastly, comparing the switching energy of transistors to modulators shows that modulators based on emerging materials and plasmonic-silicon hybrid integration perform on-par relative to their electronic counter parts. This in turn allows for a device-enabled two orders-of-magnitude improvement of electrical-optical co-integrated network-on-chips over electronic-only architectures. The latter opens technological opportunities in cognitive computing, dynamic data-driven applications systems, and optical analog computer engines including neuromorphic photonic computing.
A biological approach to assembling tissue modules through endothelial capillary network formation.
Riesberg, Jeremiah J; Shen, Wei
2015-09-01
To create functional tissues having complex structures, bottom-up approaches to assembling small tissue modules into larger constructs have been emerging. Most of these approaches are based on chemical reactions or physical interactions at the interface between tissue modules. Here we report a biological assembly approach to integrate small tissue modules through endothelial capillary network formation. When adjacent tissue modules contain appropriate extracellular matrix materials and cell types that support robust endothelial capillary network formation, capillary tubules form and grow across the interface, resulting in assembly of the modules into a single, larger construct. It was shown that capillary networks formed in modules of dense fibrin gels seeded with human umbilical vein endothelial cells (HUVECs) and mesenchymal stem cells (MSCs); adjacent modules were firmly assembled into an integrated construct having a strain to failure of 117 ± 26%, a tensile strength of 2208 ± 83 Pa and a Young's modulus of 2548 ± 574 Pa. Under the same culture conditions, capillary networks were absent in modules of dense fibrin gels seeded with either HUVECs or MSCs alone; adjacent modules disconnected even when handled gently. This biological assembly approach eliminates the need for chemical reactions or physical interactions and their associated limitations. In addition, the integrated constructs are prevascularized, and therefore this bottom-up assembly approach may also help address the issue of vascularization, another key challenge in tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.
Mittan, Margaret Birmingham [Oakland, CA; Miros, Robert H. J. [Fairfax, CA; Brown, Malcolm P [San Francisco, CA; Stancel, Robert [Loss Altos Hills, CA
2012-06-05
A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.
Brown, Malcolm P.; Mittan, Margaret Birmingham; Miros, Robert H. J.; Stancel, Robert
2013-03-19
A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.
The Fluids Integrated Rack and Light Microscopy Module Integrated Capabilities
NASA Technical Reports Server (NTRS)
Motil, Susan M.; Gati, Frank; Snead, John H.; Hill, Myron E.; Griffin, DeVon W.
2003-01-01
The Fluids Integrated Rack (FIR), a facility class payload, and the Light Microscopy Module (LMM), a subrack payload, are scheduled to be launched in 2005. The LMM integrated into the FIR will provide a unique platform for conducting fluids and biological experiments on ISS. The FIR is a modular, multi-user scientific research facility that will fly in the U.S. laboratory module, Destiny, of the International Space Station (ISS). The first payload in the FIR will be the Light Microscopy Module (LMM). The LMM is planned as a remotely controllable, automated, on-orbit microscope subrack facility, allowing flexible scheduling and control of fluids and biology experiments within the FIR. Key diagnostic capabilities for meeting science requirements include video microscopy to observe microscopic phenomena and dynamic interactions, interferometry to make thin film measurements with nanometer resolution, laser tweezers for particle manipulation, confocal microscopy to provide enhanced three-dimensional visualization of structures, and spectrophotometry to measure photonic properties of materials. The LMM also provides experiment sample containment for frangibles and fluids. This paper will provide a description of the current FIR and LMM designs, planned capabilities and key features. In addition a brief description of the initial five experiments planned for LMM/FIR will be provided.
NASA Astrophysics Data System (ADS)
Pratt-Sitaula, B. A.; Shervais, K.; Crosby, C. J.; Douglas, B. J.; Niemi, N. A.; Wang, G.; Charlevoix, D. J.
2015-12-01
Fieldwork is an integral part of the geosciences and there is a longstanding tradition of teaching field methods as part of the undergraduate curriculum. As new technology changes the ways in which we scientifically examine the Earth, and as workforce development demands evolve, there is growing interest in introducing these new technologies into field education courses. In collaboration with field education instructors, UNAVCO, the National Science Foundation's geodetic facility, has developed a module of teaching resources to integrate terrestrial lidar scanning into field courses. An NSF facility is well positioned to develop scalable resources that can then be distributed or adapted for broader implementation. The modules can also be accomplished using Structure from Motion methods in place of lidar scanning. Modules goals are for students to be able to: (A) design and conduct a complex TLS survey to address a geologic research question and (B) articulate the societal impetus for answering these research questions and identify why TLS is the appropriate method in some circumstances. The module is comprised of five units: (1) Introduction to survey design, (2) Stratigraphic section analysis, (3) Fault scarp analysis, (4) Geomorphic change detection, (5) Student-led survey design summative assessment. The modules, apart from the Introduction, are independent, thus select modules can be employed in a given field setting. Prototype module materials were developed from the last five years of UNAVCO support of undergraduate field courses. The current versions of the modules were tested in summer 2015 at the Indiana University and University of Michigan field camps. Results show that the majority of students are able to achieve the intended learning goals. Module materials are available on the UNAVCO Education and Community Engagement website.
Remote sensing training for Corps of Engineering personnel: The university training module concept
NASA Technical Reports Server (NTRS)
1982-01-01
A concept to permit Corps of Engineers personnel to obtain and maintain an appropriate level of individual proficiency in the application of remote sensing to water resource management is described. Recommendations are made for specific training courses and include structure and staffing requirements, syllabi and methods of operation, supporting materials, and procedures for integrating information systems management into the University Training Modules.
Monolithically integrated active optical devices. [with application in optical communication
NASA Technical Reports Server (NTRS)
Ballantyne, J.; Wagner, D. K.; Kushner, B.; Wojtzcuk, S.
1981-01-01
Considerations relevant to the monolithic integration of optical detectors, lasers, and modulators with high speed amplifiers are discussed. Some design considerations for representative subsystems in the GaAs-AlGaAs and GaInAs-InP materials systems are described. Results of a detailed numerical design of an electro-optical birefringent filter for monolithic integration with a laser diode is described, and early experimental results on monolithic integration of broadband MESFET amplifiers with photoconductive detectors are reported.
NASA Astrophysics Data System (ADS)
Wałach, Daniel; Sagan, Joanna; Gicala, Magdalena
2017-10-01
The paper presents an environmental and economic analysis of the material solutions of multi-level garage. The construction project approach considered reinforced concrete structure under conditions of use of ordinary concrete and high-performance concrete (HPC). Using of HPC allowed to significant reduction of reinforcement steel, mainly in compression elements (columns) in the construction of the object. The analysis includes elements of the methodology of integrated lice cycle design (ILCD). By making multi-criteria analysis based on established weight of the economic and environmental parameters, three solutions have been evaluated and compared within phase of material production (information modules A1-A3).
NASA Astrophysics Data System (ADS)
Liu, Ming; Yin, Xiaobo; Wang, Feng; Zhang, Xiang
2011-10-01
Data communications have been growing at a speed even faster than Moore's Law, with a 44-fold increase expected within the next 10 years. Data Transfer on such scale would have to recruit optical communication technology and inspire new designs of light sources, modulators, and photodetectors. An ideal optical modulator will require high modulation speed, small device footprint and large operating bandwidth. Silicon modulators based on free carrier plasma dispersion effect and compound semiconductors utilizing direct bandgap transition have seen rapid improvement over the past decade. One of the key limitations for using silicon as modulator material is its weak refractive index change, which limits the footprint of silicon Mach-Zehnder interferometer modulators to millimeters. Other approaches such as silicon microring modulators reduce the operation wavelength range to around 100 pm and are highly sensitive to typical fabrication tolerances and temperature fluctuations. Growing large, high quality wafers of compound semiconductors, and integrating them on silicon or other substrates is expensive, which also restricts their commercialization. In this work, we demonstrate that graphene can be used as the active media for electroabsorption modulators. By tuning the Fermi energy level of the graphene layer, we induced changes in the absorption coefficient of graphene at communication wavelength and achieve a modulation depth above 3 dB. This integrated device also has the potential of working at high speed.
Components for IFOG based inertial measurement units using active and passive polymer materials
NASA Astrophysics Data System (ADS)
Ashley, Paul R.; Temmen, Mark G.; Diffey, William M.; Sanghadasa, Mohan; Bramson, Michael D.; Lindsay, Geoffrey A.; Guenthner, Andrew J.
2006-08-01
Highly accurate, compact, and low cost inertial measurement units (IMUs) are needed for precision guidance in navigation systems. Active and passive polymer materials have been successfully used in fabricating two of the key guided-wave components, the phase modulator and the optical transceiver, for IMUs based on the interferometric fiber optic gyroscope (IFOG) technology. Advanced hybrid waveguide fabrication processes and novel optical integration techniques have been introduced. Backscatter compensated low loss phase modulators with low half-wave drive voltage (V π) have been fabricated with CLD- and FTC- type high performance electro-optic chromophores. A silicon-bench architecture has been used in fabricating high gain low noise transceivers with high optical power while maintaining the spectral quality and long lifetime. Gyro bias stability of less than 0.02 deg/hr has been demonstrated with these components. A review of the novel concepts introduced, fabrication and integration techniques developed and performance achieved are presented.
Flexible integration of free-standing nanowires into silicon photonics.
Chen, Bigeng; Wu, Hao; Xin, Chenguang; Dai, Daoxin; Tong, Limin
2017-06-14
Silicon photonics has been developed successfully with a top-down fabrication technique to enable large-scale photonic integrated circuits with high reproducibility, but is limited intrinsically by the material capability for active or nonlinear applications. On the other hand, free-standing nanowires synthesized via a bottom-up growth present great material diversity and structural uniformity, but precisely assembling free-standing nanowires for on-demand photonic functionality remains a great challenge. Here we report hybrid integration of free-standing nanowires into silicon photonics with high flexibility by coupling free-standing nanowires onto target silicon waveguides that are simultaneously used for precise positioning. Coupling efficiency between a free-standing nanowire and a silicon waveguide is up to ~97% in the telecommunication band. A hybrid nonlinear-free-standing nanowires-silicon waveguides Mach-Zehnder interferometer and a racetrack resonator for significantly enhanced optical modulation are experimentally demonstrated, as well as hybrid active-free-standing nanowires-silicon waveguides circuits for light generation. These results suggest an alternative approach to flexible multifunctional on-chip nanophotonic devices.Precisely assembling free-standing nanowires for on-demand photonic functionality remains a challenge. Here, Chen et al. integrate free-standing nanowires into silicon waveguides and show all-optical modulation and light generation on silicon photonic chips.
III-nitride integration on ferroelectric materials of lithium niobate by molecular beam epitaxy
NASA Astrophysics Data System (ADS)
Namkoong, Gon; Lee, Kyoung-Keun; Madison, Shannon M.; Henderson, Walter; Ralph, Stephen E.; Doolittle, W. Alan
2005-10-01
Integration of III-nitride electrical devices on the ferroelectric material lithium niobate (LiNbO3) has been demonstrated. As a ferroelectric material, lithium niobate has a polarization which may provide excellent control of the polarity of III-nitrides. However, while high temperature, 1000°C, thermal treatments produce atomically smooth surfaces, improving adhesion of GaN epitaxial layers on lithium niobate, repolarization of the substrate in local domains occurs. These effects result in multi domains of mixed polarization in LiNbO3, producing inversion domains in subsequent GaN epilayers. However, it is found that AlN buffer layers suppress inversion domains of III-nitrides. Therefore, two-dimensional electron gases in AlGaN /GaN heterojunction structures are obtained. Herein, the demonstration of the monolithic integration of high power devices with ferroelectric materials presents possibilities to control LiNbO3 modulators on compact optoelectronic/electronic chips.
Support systems of the orbiting quarantine facility
NASA Technical Reports Server (NTRS)
1981-01-01
The physical support systems, the personnel management structure, and the contingency systems necessary to permit the Orbiting Quarantine Facility (OQF) to function as an integrated system are described. The interactions between the subsystems within the preassembled modules are illustrated. The Power Module generates and distributes electrical power throughout each of the four modules, stabilizes the OQF's attitude, and dissipates heat generated throughout the system. The Habitation Module is a multifunctional structure designed to monitor and control all aspects of the system's activities. The Logistics Module stores the supplies needed for 30 days of operation and provides storage for waste materials generated during the mission. The Laboratory Module contains the equipment necessary for executing the protocol, as well as an independent life support system.
Addendum to the User Manual for NASGRO Elastic-Plastic Fracture Mechanics Software Module
NASA Technical Reports Server (NTRS)
Gregg, M. Wayne (Technical Monitor); Chell, Graham; Gardner, Brian
2003-01-01
The elastic-plastic fracture mechanics modules in NASGRO have been enhanced by the addition of of the following: new J-integral solutions based on the reference stress method and finite element solutions; the extension of the critical crack and critical load modules for cracks with two degrees of freedom that tear and failure by ductile instability; the addition of a proof test analysis module that includes safe life analysis, calculates proof loads, and determines the flaw screening 1 capability for a given proof load; the addition of a tear-fatigue module for ductile materials that simultaneously tear and extend by fatigue; and a multiple cycle proof test module for estimating service reliability following a proof test.
Stimulated Raman scattering microscopy by Nyquist modulation of a two-branch ultrafast fiber source.
Riek, Claudius; Kocher, Claudius; Zirak, Peyman; Kölbl, Christoph; Fimpel, Peter; Leitenstorfer, Alfred; Zumbusch, Andreas; Brida, Daniele
2016-08-15
A highly stable setup for stimulated Raman scattering (SRS) microscopy is presented. It is based on a two-branch femtosecond Er:fiber laser operating at a 40 MHz repetition rate. One of the outputs is directly modulated at the Nyquist frequency with an integrated electro-optic modulator (EOM). This compact source combines a jitter-free pulse synchronization with a broad tunability and allows for shot-noise limited SRS detection. The performance of the SRS microscope is illustrated with measurements on samples from material science and cell biology.
Ivanov, Alexander I.; Lushchikov, Vladislav I.; Shabalin, Eugeny P.; Maznyy, Nikita G.; Khvastunov, Michael M.; Rowland, Mark
2002-01-01
A detector for fissile materials which provides for integrity monitoring of fissile materials and can be used for nondestructive assay to confirm the presence of a stable content of fissile material in items. The detector has a sample cavity large enough to enable assay of large items of arbitrary configuration, utilizes neutron sources fabricated in spatially extended shapes mounted on the endcaps of the sample cavity, incorporates a thermal neutron filter insert with reflector properties, and the electronics module includes a neutron multiplicity coincidence counter.
Conceptual design of a hybrid Ge:Ga detector array
NASA Technical Reports Server (NTRS)
Parry, C. M.
1984-01-01
For potential applications in space infrared astronomy missions such as the Space Infrared Telescope Facility and the Large Deployable Reflector, integrated arrays of long-wavelength detectors are desired. The results of a feasibility study which developed a design for applying integrated array techniques to a long-wavelength (gallium-doped germanium) material to achieve spectral coverage between 30 and 200 microns are presented. An approach which builds up a two-dimensional array by stacking linear detector modules is presented. The spectral response of the Ge:Ga detectors is extended to 200 microns by application of uniaxial stress to the stack of modules. The detectors are assembled with 1 mm spacing between the elements. Multiplexed readout of each module is accomplished with integration sampling of a metal-oxide-semiconductor (MOS) switch chip. Aspects of the overall design, including the anticipated level of particle effects on the array in the space environment, a transparent electrode design for 200 microns response, estimates of optical crosstalk, and mechanical stress design calculations are included.
Lee, Sung-Min; Biswas, Roshni; Li, Weigu; Kang, Dongseok; Chan, Lesley; Yoon, Jongseung
2014-10-28
Nanostructured forms of crystalline silicon represent an attractive materials building block for photovoltaics due to their potential benefits to significantly reduce the consumption of active materials, relax the requirement of materials purity for high performance, and hence achieve greatly improved levelized cost of energy. Despite successful demonstrations for their concepts over the past decade, however, the practical application of nanostructured silicon solar cells for large-scale implementation has been hampered by many existing challenges associated with the consumption of the entire wafer or expensive source materials, difficulties to precisely control materials properties and doping characteristics, or restrictions on substrate materials and scalability. Here we present a highly integrable materials platform of nanostructured silicon solar cells that can overcome these limitations. Ultrathin silicon solar microcells integrated with engineered photonic nanostructures are fabricated directly from wafer-based source materials in configurations that can lower the materials cost and can be compatible with deterministic assembly procedures to allow programmable, large-scale distribution, unlimited choices of module substrates, as well as lightweight, mechanically compliant constructions. Systematic studies on optical and electrical properties, photovoltaic performance in experiments, as well as numerical modeling elucidate important design rules for nanoscale photon management with ultrathin, nanostructured silicon solar cells and their interconnected, mechanically flexible modules, where we demonstrate 12.4% solar-to-electric energy conversion efficiency for printed ultrathin (∼ 8 μm) nanostructured silicon solar cells when configured with near-optimal designs of rear-surface nanoposts, antireflection coating, and back-surface reflector.
Toward an Integrated Online Learning Environment
NASA Astrophysics Data System (ADS)
Teodorescu, Raluca E.; Pawl, Andrew; Rayyan, Saif; Barrantes, Analia; Pritchard, David E.
2010-10-01
We are building in LON-CAPA an integrated learning environment that will enable the development, dissemination and evaluation of PER-based material. This environment features a collection of multi-level research-based homework sets organized by topic and cognitive complexity. These sets are associated with learning modules that contain very short exposition of the content supplemented by integrated open-access videos, worked examples, simulations, and tutorials (some from ANDES). To assess students' performance accurately with respect to a system-wide standard, we plan to implement Item Response Theory. Together with other PER assessments and purposeful solicitation of student feedback, this will allow us to measure and improve the efficacy of various research-based materials, while getting insights into teaching and learning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, F.; Flach, G.
This report describes work performed by the Savannah River National Laboratory (SRNL) in fiscal year 2014 to develop a new Cementitious Barriers Project (CBP) software module designated as FLOExcel. FLOExcel incorporates a uniform database to capture material characterization data and a GoldSim model to define flow properties for both intact and fractured cementitious materials and estimate Darcy velocity based on specified hydraulic head gradient and matric tension. The software module includes hydraulic parameters for intact cementitious and granular materials in the database and a standalone GoldSim framework to manipulate the data. The database will be updated with new data asmore » it comes available. The software module will later be integrated into the next release of the CBP Toolbox, Version 3.0. This report documents the development efforts for this software module. The FY14 activities described in this report focused on the following two items that form the FLOExcel package; 1) Development of a uniform database to capture CBP data for cementitious materials. In particular, the inclusion and use of hydraulic properties of the materials are emphasized; and 2) Development of algorithms and a GoldSim User Interface to calculate hydraulic flow properties of degraded and fractured cementitious materials. Hydraulic properties are required in a simulation of flow through cementitious materials such as Saltstone, waste tank fill grout, and concrete barriers. At SRNL these simulations have been performed using the PORFLOW code as part of Performance Assessments for salt waste disposal and waste tank closure.« less
Project TIMS (Teaching Integrated Math/Science)
NASA Technical Reports Server (NTRS)
Edwards, Leo, Jr.
1993-01-01
The goal of this project is to increase the scientific knowledge and appreciation bases and skills of pre-service and in-service middle school teachers, so as to impact positively on teaching, learning, and student retention. This report lists the objectives and summarizes the progress thus far. Included is the working draft of the TIMS (Teaching Integrated Math/Science) curriculum outline. Seven of the eight instructional subject-oriented modules are also included. The modules include informative materials and corresponding questions and educational activities in a textbook format. The subjects included here are the universe and stars; the sun and its place in the universe; our solar system; astronomical instruments and scientific measurements; the moon and eclipses; the earth's atmosphere: its nature and composition; and the earth: directions, time, and seasons. The module not included regards winds and circulation.
Low frequency piezoresonance defined dynamic control of terahertz wave propagation
NASA Astrophysics Data System (ADS)
Dutta, Moumita; Betal, Soutik; Peralta, Xomalin G.; Bhalla, Amar S.; Guo, Ruyan
2016-11-01
Phase modulators are one of the key components of many applications in electromagnetic and opto-electric wave propagations. Phase-shifters play an integral role in communications, imaging and in coherent material excitations. In order to realize the terahertz (THz) electromagnetic spectrum as a fully-functional bandwidth, the development of a family of efficient THz phase modulators is needed. Although there have been quite a few attempts to implement THz phase modulators based on quantum-well structures, liquid crystals, or meta-materials, significantly improved sensitivity and dynamic control for phase modulation, as we believe can be enabled by piezoelectric-resonance devices, is yet to be investigated. In this article we provide an experimental demonstration of phase modulation of THz beam by operating a ferroelectric single crystal LiNbO3 film device at the piezo-resonance. The piezo-resonance, excited by an external a.c. electric field, develops a coupling between electromagnetic and lattice-wave and this coupling governs the wave propagation of the incident THz beam by modulating its phase transfer function. We report the understanding developed in this work can facilitate the design and fabrication of a family of resonance-defined highly sensitive and extremely low energy sub-millimeter wave sensors and modulators.
Low frequency piezoresonance defined dynamic control of terahertz wave propagation.
Dutta, Moumita; Betal, Soutik; Peralta, Xomalin G; Bhalla, Amar S; Guo, Ruyan
2016-11-30
Phase modulators are one of the key components of many applications in electromagnetic and opto-electric wave propagations. Phase-shifters play an integral role in communications, imaging and in coherent material excitations. In order to realize the terahertz (THz) electromagnetic spectrum as a fully-functional bandwidth, the development of a family of efficient THz phase modulators is needed. Although there have been quite a few attempts to implement THz phase modulators based on quantum-well structures, liquid crystals, or meta-materials, significantly improved sensitivity and dynamic control for phase modulation, as we believe can be enabled by piezoelectric-resonance devices, is yet to be investigated. In this article we provide an experimental demonstration of phase modulation of THz beam by operating a ferroelectric single crystal LiNbO 3 film device at the piezo-resonance. The piezo-resonance, excited by an external a.c. electric field, develops a coupling between electromagnetic and lattice-wave and this coupling governs the wave propagation of the incident THz beam by modulating its phase transfer function. We report the understanding developed in this work can facilitate the design and fabrication of a family of resonance-defined highly sensitive and extremely low energy sub-millimeter wave sensors and modulators.
Ye, Xuan; Cui, Zhiguo; Fang, Huajun; Li, Xide
2017-01-01
We report a novel material testing system (MTS) that uses hierarchical designs for in-situ mechanical characterization of multiscale materials. This MTS is adaptable for use in optical microscopes (OMs) and scanning electron microscopes (SEMs). The system consists of a microscale material testing module (m-MTM) and a nanoscale material testing module (n-MTM). The MTS can measure mechanical properties of materials with characteristic lengths ranging from millimeters to tens of nanometers, while load capacity can vary from several hundred micronewtons to several nanonewtons. The m-MTM is integrated using piezoelectric motors and piezoelectric stacks/tubes to form coarse and fine testing modules, with specimen length from millimeters to several micrometers, and displacement distances of 12 mm with 0.2 µm resolution for coarse level and 8 µm with 1 nm resolution for fine level. The n-MTM is fabricated using microelectromechanical system technology to form active and passive components and realizes material testing for specimen lengths ranging from several hundred micrometers to tens of nanometers. The system’s capabilities are demonstrated by in-situ OM and SEM testing of the system’s performance and mechanical properties measurements of carbon fibers and metallic microwires. In-situ multiscale deformation tests of Bacillus subtilis filaments are also presented. PMID:28777341
Active 2D materials for on-chip nanophotonics and quantum optics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shiue, Ren-Jye; Efetov, Dmitri K.; Grosso, Gabriele
Abstract Two-dimensional materials have emerged as promising candidates to augment existing optical networks for metrology, sensing, and telecommunication, both in the classical and quantum mechanical regimes. Here, we review the development of several on-chip photonic components ranging from electro-optic modulators, photodetectors, bolometers, and light sources that are essential building blocks for a fully integrated nanophotonic and quantum photonic circuit.
Active 2D materials for on-chip nanophotonics and quantum optics
NASA Astrophysics Data System (ADS)
Shiue, Ren-Jye; Efetov, Dmitri K.; Grosso, Gabriele; Peng, Cheng; Fong, Kin Chung; Englund, Dirk
2017-03-01
Two-dimensional materials have emerged as promising candidates to augment existing optical networks for metrology, sensing, and telecommunication, both in the classical and quantum mechanical regimes. Here, we review the development of several on-chip photonic components ranging from electro-optic modulators, photodetectors, bolometers, and light sources that are essential building blocks for a fully integrated nanophotonic and quantum photonic circuit.
A MoTe2 based light emitting diode and photodetector for silicon photonic integrated circuits
NASA Astrophysics Data System (ADS)
Bie, Ya-Qing; Heuck, M.; Grosso, G.; Furchi, M.; Cao, Y.; Zheng, J.; Navarro-Moratalla, E.; Zhou, L.; Taniguchi, T.; Watanabe, K.; Kong, J.; Englund, D.; Jarillo-Herrero, P.
A key challenge in photonics today is to address the interconnects bottleneck in high-speed computing systems. Silicon photonics has emerged as a leading architecture, partly because many components such as waveguides, interferometers and modulators, could be integrated on silicon-based processors. However, light sources and photodetectors present continued challenges. Common approaches for light source include off-chip or wafer-bonded lasers based on III-V materials, but studies show advantages for directly modulated light sources. The most advanced photodetectors in silicon photonics are based on germanium growth which increases system cost. The emerging two dimensional transition metal dichalcogenides (TMDs) offer a path for optical interconnects components that can be integrated with the CMOS processing by back-end-of-the-line processing steps. Here we demonstrate a silicon waveguide-integrated light source and photodetector based on a p-n junction of bilayer MoTe2, a TMD semiconductor with infrared band gap. The state-of-the-art fabrication technology provides new opportunities for integrated optoelectronic systems.
High-performance packaging for monolithic microwave and millimeter-wave integrated circuits
NASA Technical Reports Server (NTRS)
Shalkhauser, K. A.; Li, K.; Shih, Y. C.
1992-01-01
Packaging schemes were developed that provide low-loss, hermetic enclosure for advanced monolithic microwave and millimeter-wave integrated circuits (MMICs). The package designs are based on a fused quartz substrate material that offers improved radio frequency (RF) performance through 44 gigahertz (GHz). The small size and weight of the packages make them appropriate for a variety of applications, including phased array antenna systems. Packages were designed in two forms; one for housing a single MMIC chip, the second in the form of a multi-chip phased array module. The single chip array module was developed in three separate sizes, for chips of different geometry and frequency requirements. The phased array module was developed to address packaging directly for antenna applications, and includes transmission line and interconnect structures to support multi-element operation. All packages are fabricated using fused quartz substrate materials. As part of the packaging effort, a test fixture was developed to interface the single chip packages to conventional laboratory instrumentation for characterization of the packaged devices. The package and test fixture designs were both developed in a generic sense, optimizing performance for a wide range of possible applications and devices.
Pattern dependence in high-speed Q-modulated distributed feedback laser.
Zhu, Hongli; Xia, Yimin; He, Jian-Jun
2015-05-04
We investigate the pattern dependence in high speed Q-modulated distributed feedback laser based on its complete physical structure and material properties. The structure parameters of the gain section as well as the modulation and phase sections are all taken into account in the simulations based on an integrated traveling wave model. Using this model, we show that an example Q-modulated DFB laser can achieve an extinction ratio of 6.8dB with a jitter of 4.7ps and a peak intensity fluctuation of less than 15% for 40Gbps RZ modulation signal. The simulation method is proved very useful for the complex laser structure design and high speed performance optimization, as well as for providing physical insight of the operation mechanism.
Seeland, Ute; Nauman, Ahmad T; Cornelis, Alissa; Ludwig, Sabine; Dunkel, Mathias; Kararigas, Georgios; Regitz-Zagrosek, Vera
2016-01-01
Sex and Gender Medicine is a novel discipline that provides equitable medical care for society and improves outcomes for both male and female patients. The integration of sex- and gender-specific knowledge into medical curricula is limited due to adequate learning material, systematic teacher training and an innovative communication strategy. We aimed at initiating an e-learning and knowledge-sharing platform for Sex and Gender Medicine, the eGender platform (http://egender.charite.de), to ensure that future doctors and health professionals will have adequate knowledge and communication skills on sex and gender differences in order to make informed decisions for their patients. The web-based eGender knowledge-sharing platform was designed to support the blended learning pedagogical teaching concept and follows the didactic concept of constructivism. Learning materials developed by Sex and Gender Medicine experts of seven universities have been used as the basis for the new learning tools . The content of these tools is patient-centered and provides add-on information on gender-sensitive aspects of diseases. The structural part of eGender was designed and developed using the open source e-learning platform Moodle. The eGender platform comprises an English and a German version of e-learning modules: one focusing on basic knowledge and seven on specific medical disciplines. Each module consists of several courses corresponding to a disease or symptom complex. Self-organized learning has to be managed by using different learning tools, e.g., texts and audiovisual material, tools for online communication and collaborative work. More than 90 users from Europe registered for the eGender Medicine learning modules. The most frequently accessed module was "Gender Medicine-Basics" and the users favored discussion forums. These e-learning modules fulfill the quality criteria for higher education and are used within the elective Master Module "Gender Medicine-Basics" implemented into the accredited Master of Public Health at Charité-Berlin. The eGender platform is a flexible and user-friendly electronical knowledge-sharing platform providing evidence-based high-quality learning material used by a growing number of registered users. The eGender Medicine learning modules could be key in the reform of medical curricula to integrate Sex and Gender Medicine into the education of health professionals.
Ultralow drive voltage silicon traveling-wave modulator.
Baehr-Jones, Tom; Ding, Ran; Liu, Yang; Ayazi, Ali; Pinguet, Thierry; Harris, Nicholas C; Streshinsky, Matt; Lee, Poshen; Zhang, Yi; Lim, Andy Eu-Jin; Liow, Tsung-Yang; Teo, Selin Hwee-Gee; Lo, Guo-Qiang; Hochberg, Michael
2012-05-21
There has been great interest in the silicon platform as a material system for integrated photonics. A key challenge is the development of a low-power, low drive voltage, broadband modulator. Drive voltages at or below 1 Vpp are desirable for compatibility with CMOS processes. Here we demonstrate a CMOS-compatible broadband traveling-wave modulator based on a reverse-biased pn junction. We demonstrate operation with a drive voltage of 0.63 Vpp at 20 Gb/s, a significant improvement in the state of the art, with an RF energy consumption of only 200 fJ/bit.
1991-01-01
EXPERIENCE IN DEVELOPING INTEGRATED OPTICAL DEVICES, NONLINEAR MAGNETIC-OPTIC MATERIALS, HIGH FREQUENCY MODULATORS, COMPUTER-AIDED MODELING AND SOPHISTICATED... HIGH -LEVEL PRESENTATION AND DISTRIBUTED CONTROL MODELS FOR INTEGRATING HETEROGENEOUS MECHANICAL ENGINEERING APPLICATIONS AND TOOLS. THE DESIGN IS FOCUSED...STATISTICALLY ACCURATE WORST CASE DEVICE MODELS FOR CIRCUIT SIMULATION. PRESENT METHODS OF WORST CASE DEVICE DESIGN ARE AD HOC AND DO NOT ALLOW THE
Development of a new integral solar cell protective cover
NASA Technical Reports Server (NTRS)
Naselow, A. B.; Dupont, P. S.; Scott-Monck, J.
1983-01-01
A unique polyimide polymer has been developed which shows promise as an encapsulant for interconnected solar cell modules. Such an integral cover offers important weight and cost advantages. The polymer has been characterized on silicon solar cells with respect to electrical output and spectral response. The response of the material-coated cells to electron, low-energy proton, and vacuum-ultraviolet radiation, thermal shock and humidity tests was determined.
Emerging technologies in Si active photonics
NASA Astrophysics Data System (ADS)
Wang, Xiaoxin; Liu, Jifeng
2018-06-01
Silicon photonics for synergistic electronic–photonic integration has achieved remarkable progress in the past two decades. Active photonic devices, including lasers, modulators, and photodetectors, are the key challenges for Si photonics to meet the requirement of high bandwidth and low power consumption in photonic datalinks. Here we review recent efforts and progress in high-performance active photonic devices on Si, focusing on emerging technologies beyond conventional foundry-ready Si photonics devices. For emerging laser sources, we will discuss recent progress towards efficient monolithic Ge lasers, mid-infrared GeSn lasers, and high-performance InAs quantum dot lasers on Si for data center applications in the near future. We will then review novel modulator materials and devices beyond the free carrier plasma dispersion effect in Si, including GeSi and graphene electro-absorption modulators and plasmonic-organic electro-optical modulators, to achieve ultralow power and high speed modulation. Finally, we discuss emerging photodetectors beyond epitaxial Ge p–i–n photodiodes, including GeSn mid-infrared photodetectors, all-Si plasmonic Schottky infrared photodetectors, and Si quanta image sensors for non-avalanche, low noise single photon detection and photon counting. These emerging technologies, though still under development, could make a significant impact on the future of large-scale electronicSilicon photonics for synergistic electronic-photonic integration has achieved remarkable progress in the past two decades. Active photonic devices, including lasers, modulators, and photodetectors, are the key challenges for Si photonics to meet the requirement of high bandwidth and low power consumption in photonic datalinks. Here we review recent efforts and progress in high-performance active photonic devices on Si, focusing on emerging technologies beyond conventional foundry-ready Si photonics devices. For emerging laser sources, we will discuss recent progress towards efficient monolithic Ge lasers, mid-infrared GeSn lasers, and high-performance InAs quantum dot lasers on Si for data center applications in the near future. We will then review novel modulator materials and devices beyond the free carrier plasma dispersion effect in Si, including GeSi and graphene electro-absorption modulators and plasmonic-organic electro–optical modulators, to achieve ultralow power and high speed modulation. Finally, we discuss emerging photodetectors beyond epitaxial Ge p–i–n photodiodes, including GeSn mid-infrared photodetectors, all-Si plasmonic Schottky infrared photodetectors, and Si quanta image sensors for non-avalanche, low noise single photon detection and photon counting. These emerging technologies, though still under development, could make a significant impact on the future of large-scale electronic–photonic integration with performance inaccessible from conventional Si photonics technologies-photonic integration with performance inaccessible from conventional Si photonics technologies.
Wafer integrated micro-scale concentrating photovoltaics
NASA Astrophysics Data System (ADS)
Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun
2017-09-01
Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bolotnikov, A. E., E-mail: bolotnik@bnl.gov; Ackley, K.; Camarda, G. S.
We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm{sup 3} detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We presentmore » the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays’ performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.« less
Thermal vacuum chamber repressurization with instrument purging
NASA Astrophysics Data System (ADS)
Woronowicz, Michael S.
2016-09-01
At the conclusion of cryogenic vacuum testing of the James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (JWST-OTIS) in NASA Johnson Space Center's (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are postulating that chamber particulate material stirred up by the repressurization process may be kept from falling into the Integrated Science Instrument Module (ISIM) interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This manuscript describes development of a series of models designed to describe this process. The models are strung together in tandem with a fictitious set of conditions to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.
Thermal Vacuum Chamber Repressurization with Instrument Purging
NASA Technical Reports Server (NTRS)
Woronowicz, Michael S.
2014-01-01
At the conclusion of cryogenic vacuum testing of the James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (JWST-OTIS) in NASA Johnson Space Center’s (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are postulating that chamber particulate material stirred up by the repressurization process may be kept from falling into the Integrated Science Instrument Module (ISIM) interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This manuscript describes development of a series of models designed to describe this process. The models are strung together in tandem with a fictitious set of conditions to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.
Advanced Colloids Experiment-1 (ACE-1)
2013-07-22
ISS036-E-023770 (22 July 2013) --- NASA astronaut Chris Cassidy, Expedition 36 flight engineer, conducts science work with the ongoing experiment Advanced Colloids Experiment-1 (ACE-1) inside the Fluids Integrated Rack. The experiment observes colloids, microscopic particles evenly dispersed throughout materials, with the potential for manufacturing improved materials and products on Earth. Cassidy is working at the Light Microscopy Module (LMM) in the Destiny laboratory of the International Space Station.
NASA Astrophysics Data System (ADS)
Neumann, Jay; Parlato, Russell; Tracy, Gregory; Randolph, Max
2015-09-01
Focal plane alignment for large format arrays and faster optical systems require enhanced precision methodology and stability over temperature. The increase in focal plane array size continues to drive the alignment capability. Depending on the optical system, the focal plane flatness of less than 25μm (.001") is required over transition temperatures from ambient to cooled operating temperatures. The focal plane flatness requirement must also be maintained in airborne or launch vibration environments. This paper addresses the challenge of the detector integration into the focal plane module and housing assemblies, the methodology to reduce error terms during integration and the evaluation of thermal effects. The driving factors influencing the alignment accuracy include: datum transfers, material effects over temperature, alignment stability over test, adjustment precision and traceability to NIST standard. The FPA module design and alignment methodology reduces the error terms by minimizing the measurement transfers to the housing. In the design, the proper material selection requires matched coefficient of expansion materials minimizes both the physical shift over temperature as well as lowering the stress induced into the detector. When required, the co-registration of focal planes and filters can achieve submicron relative positioning by applying precision equipment, interferometry and piezoelectric positioning stages. All measurements and characterizations maintain traceability to NIST standards. The metrology characterizes the equipment's accuracy, repeatability and precision of the measurements.
Bolotnikov, A E; Ackley, K; Camarda, G S; Cherches, C; Cui, Y; De Geronimo, G; Fried, J; Hodges, D; Hossain, A; Lee, W; Mahler, G; Maritato, M; Petryk, M; Roy, U; Salwen, C; Vernon, E; Yang, G; James, R B
2015-07-01
We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm(3) detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays' performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.
2006-07-13
echnology T ervicesS Integrated Systems & Solutions Integrated yste s S olutionsS • 30,000 Employees • 5 Principal Businesses Organized Into 3 Major...Solutions -Data Sources -Search Engine -Notification Policy -DSCC/IST Lead -Industry Capabilities - Organic Capabilities -Pro-active upgrades -DMEA Lead...needs to TLCSM EC. Cathi Crabtree Voting Members Accomplishments WG Organization we can build on DAU Distance Leaning Modules WG Strategic Plan Re
An Interdisciplinary Module on Regulating Carbon Emissions to Mitigate Climate Change
NASA Astrophysics Data System (ADS)
Penny, S.; Sethi, G.; Smyth, R.; Leibensperger, E. M.; Gervich, C.; Batur, P.
2016-12-01
The dynamics of the unfolding carbon regulatory process presents a unique and timely opportunity to teach students about the grand challenge brought by climate change and the importance of systems thinking and interdisciplinary problem solving. In this poster, we summarize our recently developed 4-week activity-based class module "Regulating Carbon Emissions to Mitigate Climate Change," which we have developed as part of the InTeGrate ("Interdisciplinary Teaching about Earth for a Sustainable Future") program. These materials are suitable for introductory non-majors, environmental sciences majors, and political science majors, and we have formally piloted in each of these settings. This module is truly interdisciplinary and spans topics such as the Supreme Court ruling in Massachusetts v. EPA, costs and benefits of carbon abatement, and climate sensitivity. We discuss the unique challenges (and rewards!) that we experienced teaching materials entirely outside one's expertise.
Electronics. Module 3: Digital Logic Application. Instructor's Guide.
ERIC Educational Resources Information Center
Carter, Ed; Murphy, Mark
This guide contains instructor's materials for a 10-unit secondary school course on digital logic application. The units are introduction to digital, logic gates, digital integrated circuits, combination logic, flip-flops, counters and shift registers, encoders and decoders, arithmetic circuits, memory, and analog/digital and digital/analog…
Materials and Chemical Science and Technology | Research | NREL
Applications and Performance Developing high-efficiency crystalline PV, measuring PV cell/module performance Cells and Hydrogen Program Developing, integrating, and demonstrating hydrogen production/delivery /storage through core programs and EFRCs Point of Contact Bill Tumas MCST Research Advisors/Fellows Senior
Compact optical transconductance varistor
Sampayan, Stephen
2015-09-22
A compact radiation-modulated transconductance varistor device having both a radiation source and a photoconductive wide bandgap semiconductor material (PWBSM) integrally formed on a substrate so that a single interface is formed between the radiation source and PWBSM for transmitting PWBSM activation radiation directly from the radiation source to the PWBSM.
NASA Astrophysics Data System (ADS)
Schiattone, Francesco; Bonino, Stefano; Gobbi, Luigi; Groppi, Angelamaria; Marazzi, Marco; Musio, Maurizio
2003-04-01
In the past the optical component market has been mainly driven by performances. Today, as the number of competitors has drastically increased, the system integrators have a wide range of possible suppliers and solutions giving them the possibility to be more focused on cost and also on footprint reduction. So, if performances are still essential, low cost and Small Form Factor issues are becoming more and more crucial in selecting components. Another evolution in the market is the current request of the optical system companies to simplify the supply chain in order to reduce the assembling and testing steps at system level. This corresponds to a growing demand in providing subassemblies, modules or hybrid integrated components: that means also Integration will be an issue in which all the optical component companies will compete to gain market shares. As we can see looking several examples offered by electronic market, to combine low cost and SFF is a very challenging task but Integration can help in achieving both features. In this work we present how these issues could be approached giving examples of some advanced solutions applied to LiNbO3 modulators. In particular we describe the progress made on automation, new materials and low cost fabrication methods for the parts. We also introduce an approach in integrating optical and electrical functionality on LiNbO3 modulators including RF driver, bias control loop, attenuator and photodiode integrated in a single device.
High Temperature Integrated Thermoelectric Ststem and Materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mike S. H. Chu
2011-06-06
The final goal of this project is to produce, by the end of Phase II, an all ceramic high temperature thermoelectric module. Such a module design integrates oxide ceramic n-type, oxide ceramic p-type materials as thermoelectric legs and oxide ceramic conductive material as metalizing connection between n-type and p-type legs. The benefits of this all ceramic module are that it can function at higher temperatures (> 700 C), it is mechanically and functionally more reliable and it can be scaled up to production at lower cost. With this all ceramic module, millions of dollars in savings or in new opportunitiesmore » recovering waste heat from high temperature processes could be made available. A very attractive application will be to convert exhaust heat from a vehicle to reusable electric energy by a thermoelectric generator (TEG). Phase I activities were focused on evaluating potential n-type and p-type oxide compositions as the thermoelectric legs. More than 40 oxide ceramic powder compositions were made and studied in the laboratory. The compositions were divided into 6 groups representing different material systems. Basic ceramic properties and thermoelectric properties of discs sintered from these powders were measured. Powders with different particles sizes were made to evaluate the effects of particle size reduction on thermoelectric properties. Several powders were submitted to a leading thermoelectric company for complete thermoelectric evaluation. Initial evaluation showed that when samples were sintered by conventional method, they had reasonable values of Seebeck coefficient but very low values of electrical conductivity. Therefore, their power factors (PF) and figure of merits (ZT) were too low to be useful for high temperature thermoelectric applications. An unconventional sintering method, Spark Plasma Sintering (SPS) was determined to produce better thermoelectric properties. Particle size reduction of powders also was found to have some positive benefits. Two composition systems, specifically 1.0 SrO - 0.8 x 1.03 TiO2 - 0.2 x 1.03 NbO2.5 and 0.97 TiO2 - 0.03 NbO2.5, have been identified as good base line compositions for n-type thermoelectric compositions in future module design. Tests of these materials at an outside company were promising using that company's processing and material expertise. There was no unique p-type thermoelectric compositions identified in phase I work other than several current cobaltite materials. Ca3Co4O9 will be the primary p-type material for the future module design until alternative materials are developed. BaTiO3 and rare earth titanate based dielectric compositions show both p-type and n-type behavior even though their electrical conductivities were very low. Further research and development of these materials for thermoelectric applications is planned in the future. A preliminary modeling and optimization of a thermoelectric generator (TEG) that uses the n-type 1.0 SrO - 1.03 x 0.8 TiO2 - 1.03 x 0.2 NbO2.5 was performed. Future work will combine development of ceramic powders and manufacturing expertise at TAM, development of SPS at TAM or a partner organization, and thermoelectric material/module testing, modeling, optimization, production at several partner organizations.« less
An integratable microfluidic cartridge for forensic swab samples lysis.
Yang, Jianing; Brooks, Carla; Estes, Matthew D; Hurth, Cedric M; Zenhausern, Frederic
2014-01-01
Fully automated rapid forensic DNA analysis requires integrating several multistep processes onto a single microfluidic platform, including substrate lysis, extraction of DNA from the released lysate solution, multiplexed PCR amplification of STR loci, separation of PCR products by capillary electrophoresis, and analysis for allelic peak calling. Over the past several years, most of the rapid DNA analysis systems developed started with the reference swab sample lysate and involved an off-chip lysis of collected substrates. As a result of advancement in technology and chemistry, addition of a microfluidic module for swab sample lysis has been achieved in a few of the rapid DNA analysis systems. However, recent reports on integrated rapid DNA analysis systems with swab-in and answer-out capability lack any quantitative and qualitative characterization of the swab-in sample lysis module, which is important for downstream forensic sample processing. Maximal collection and subsequent recovery of the biological material from the crime scene is one of the first and critical steps in forensic DNA technology. Herein we present the design, fabrication and characterization of an integratable swab lysis cartridge module and the test results obtained from different types of commonly used forensic swab samples, including buccal, saliva, and blood swab samples, demonstrating the compatibility with different downstream DNA extraction chemistries. This swab lysis cartridge module is easy to operate, compatible with both forensic and microfluidic requirements, and ready to be integrated with our existing automated rapid forensic DNA analysis system. Following the characterization of the swab lysis module, an integrated run from buccal swab sample-in to the microchip CE electropherogram-out was demonstrated on the integrated prototype instrument. Therefore, in this study, we demonstrate that this swab lysis cartridge module is: (1) functionally, comparable with routine benchtop lysis, (2) compatible with various types of swab samples and chemistries, and (3) integratable to achieve a micro total analysis system (μTAS) for rapid DNA analysis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Integration of carbon nanotubes in slot waveguides (Conference Presentation)
NASA Astrophysics Data System (ADS)
Durán-Valdeiglesias, Elena; Zhang, Weiwei; Hoang, Thi Hong Cam; Alonso-Ramos, Carlos; Serna, Samuel; Le Roux, Xavier; Cassan, Eric; Balestrieri, Matteo; Keita, Al-Saleh; Sarti, Francesco; Biccari, Francesco; Torrini, Ughetta; Vinattieri, Anna; Yang, Hongliu; Bezugly, Viktor; Cuniberti, Gianaurelio; Filoramo, Arianna; Gurioli, Massimo; Vivien, Laurent
2016-05-01
Demanding applications such as video streaming, social networking, or web search relay on a large network of data centres, interconnected through optical links. The ever-growing data rates and power consumption inside these data centres are pushing copper links close to their fundamental limits. Optical interconnects are being extensively studied with the purpose of solving these limitations. Among the different possible technology platforms, silicon photonics, due to its compatibility with the CMOS platform, has become one of the preferred solutions for the development of the future generation photonic interconnects. However, the on-chip integration of all photonic and optoelectronic building blocks (sources, modulators and detectors…) is very complex and is not cost-effective due to the various materials involved (Ge for detection, doped Si for modulators and III-V for lasing). Carbon nanotubes (CNTs) are nanomaterials of great interest in photonics thanks to their fundamental optical properties, including near-IR room-temperature foto- and electro- luminescence, Stark effect, Kerr effect and absorption. In consequence, CNTs have the ability to emit, modulate and detect light in the telecommunications wavelength range. Furthermore, they are being extensively developed for new nano-electronics applications. In this work, we propose to use CNTs as active material integrated into silicon photonics for the development of all optoelectronic devices. Here, we report on the development of new integration schemes to couple the light emission from CNTs into optical resonators implemented on the silicon-on-insulator and silicon-nitride-on-insulator platforms. A theoretical and experimental analysis of the light interaction of CNTs with micro-ring resonators based on strip and slot waveguides and slot photonic crystal heterostructure cavities were carried out.
NASA Astrophysics Data System (ADS)
Palodiya, Vikram; Raghuwanshi, Sanjeev Kumar
2017-12-01
In this paper, the domain inversion is used in a simple fashion to improve the performance of a Z-cut highly integrated LiNbO3 optical modulator (LNOM). The Z-cut modulator having ≤ 3 V switching voltage and bandwidth of 15 GHz for an external modulator in which traveling-wave electrode length L_{m} imposed the modulating voltage, the product of V_π and L_{m} is fixed for a given electro-optic material (EOM). An investigation to achieve a low V_π by both magnitude of the electro-optic coefficient (EOC) for a wide variety of EOMs has been reported. The Sellmeier equation (SE) for the extraordinary index of congruent LiNbO3 is derived. The predictions related to phase matching are accurate between room temperature and 250 °C and wavelength ranging from 0.4 to 5 μm. The SE predicts more accurate refractive indices (RI) at long wavelengths. The different overlaps between the waveguides for the Z-cut structure are shown to yield a chirp parameter that can able to adjust 0-0.7. Theoretical results are perfectly verified by simulated results.
NASA Astrophysics Data System (ADS)
Kleinert, M.; Reinke, P.; Bach, H.-G.; Brinker, W.; Zawadzki, C.; Dietrich, A.; de Felipe, D.; Keil, N.; Schell, M.
2017-02-01
Graphene with its high carrier mobility as well as its tunable light absorption is an attractive active material for highspeed electro-absorption modulators (EAMs). Large-area CVD-grown graphene monolayers can be transferred onto arbitrary substrates to add active optoelectronic properties to intrinsically passive photonic integration platforms. In this work, we present graphene-based EAMs integrated in passive polymer waveguides. To facilitate modulation frequencies in the GHz range, a 50 Ω termination resistor as well as a DC blocking capacitor are integrated with graphene EAMs for the first time. Large signal data transmission experiments were carried out across the O, C and L optical communications bands. The fastest devices exhibit a 3-dB bandwidth of more than 4 GHz. Our analytical model of the modulation response for the graphene-based EAMs is in good agreement with the measurement results. It predicts that bandwidths greater than 50 GHz are possible with future device iterations. Owing to the absorption properties of the graphene layers, the devices are expected to be functional at smaller wavelengths of interest for optical interconnects and data-communications as well, offering a novel flexibility for the integration of high-speed functionalities in optoelectronic integrated circuits. Our work is the first step towards an Active Optical Printed Circuit Board, hiding the optics completely inside the board and thus removing entry barriers in manufacturing. We believe this will lead to the same success as observed in Active Optical Cables for short range optically wired connections.
Xu, Wei-Ming; Yang, Kuo; Jiang, Li-Jie; Hu, Jing-Qing; Zhou, Xue-Zhong
2018-01-01
Background: Ischemic heart disease (IHD) has been the leading cause of death for several decades globally, IHD patients usually hold the symptoms of phlegm-stasis cementation syndrome (PSCS) as significant complications. However, the underlying molecular mechanisms of PSCS complicated with IHD have not yet been fully elucidated. Materials and Methods: Network medicine methods were utilized to elucidate the underlying molecular mechanisms of IHD phenotypes. Firstly, high-quality IHD-associated genes from both human curated disease-gene association database and biomedical literatures were integrated. Secondly, the IHD disease modules were obtained by dissecting the protein-protein interaction (PPI) topological modules in the String V9.1 database and the mapping of IHD-associated genes to the PPI topological modules. After that, molecular functional analyses (e.g., Gene Ontology and pathway enrichment analyses) for these IHD disease modules were conducted. Finally, the PSCS syndrome modules were identified by mapping the PSCS related symptom-genes to the IHD disease modules, which were further validated by both pharmacological and physiological evidences derived from published literatures. Results: The total of 1,056 high-quality IHD-associated genes were integrated and evaluated. In addition, eight IHD disease modules (the PPI sub-networks significantly relevant to IHD) were identified, in which two disease modules were relevant to PSCS syndrome (i.e., two PSCS syndrome modules). These two modules had enriched pathways on Toll-like receptor signaling pathway (hsa04620) and Renin-angiotensin system (hsa04614), with the molecular functions of angiotensin maturation (GO:0002003) and response to bacterium (GO:0009617), which had been validated by classical Chinese herbal formulas-related targets, IHD-related drug targets, and the phenotype features derived from human phenotype ontology (HPO) and published biomedical literatures. Conclusion: A network medicine-based approach was proposed to identify the underlying molecular modules of PSCS complicated with IHD, which could be used for interpreting the pharmacological mechanisms of well-established Chinese herbal formulas ( e.g., Tao Hong Si Wu Tang, Dan Shen Yin, Hunag Lian Wen Dan Tang and Gua Lou Xie Bai Ban Xia Tang ). In addition, these results delivered novel understandings of the molecular network mechanisms of IHD phenotype subtypes with PSCS complications, which would be both insightful for IHD precision medicine and the integration of disease and TCM syndrome diagnoses.
Xu, Wei-Ming; Yang, Kuo; Jiang, Li-Jie; Hu, Jing-Qing; Zhou, Xue-Zhong
2018-01-01
Background: Ischemic heart disease (IHD) has been the leading cause of death for several decades globally, IHD patients usually hold the symptoms of phlegm-stasis cementation syndrome (PSCS) as significant complications. However, the underlying molecular mechanisms of PSCS complicated with IHD have not yet been fully elucidated. Materials and Methods: Network medicine methods were utilized to elucidate the underlying molecular mechanisms of IHD phenotypes. Firstly, high-quality IHD-associated genes from both human curated disease-gene association database and biomedical literatures were integrated. Secondly, the IHD disease modules were obtained by dissecting the protein-protein interaction (PPI) topological modules in the String V9.1 database and the mapping of IHD-associated genes to the PPI topological modules. After that, molecular functional analyses (e.g., Gene Ontology and pathway enrichment analyses) for these IHD disease modules were conducted. Finally, the PSCS syndrome modules were identified by mapping the PSCS related symptom-genes to the IHD disease modules, which were further validated by both pharmacological and physiological evidences derived from published literatures. Results: The total of 1,056 high-quality IHD-associated genes were integrated and evaluated. In addition, eight IHD disease modules (the PPI sub-networks significantly relevant to IHD) were identified, in which two disease modules were relevant to PSCS syndrome (i.e., two PSCS syndrome modules). These two modules had enriched pathways on Toll-like receptor signaling pathway (hsa04620) and Renin-angiotensin system (hsa04614), with the molecular functions of angiotensin maturation (GO:0002003) and response to bacterium (GO:0009617), which had been validated by classical Chinese herbal formulas-related targets, IHD-related drug targets, and the phenotype features derived from human phenotype ontology (HPO) and published biomedical literatures. Conclusion: A network medicine-based approach was proposed to identify the underlying molecular modules of PSCS complicated with IHD, which could be used for interpreting the pharmacological mechanisms of well-established Chinese herbal formulas (e.g., Tao Hong Si Wu Tang, Dan Shen Yin, Hunag Lian Wen Dan Tang and Gua Lou Xie Bai Ban Xia Tang). In addition, these results delivered novel understandings of the molecular network mechanisms of IHD phenotype subtypes with PSCS complications, which would be both insightful for IHD precision medicine and the integration of disease and TCM syndrome diagnoses. PMID:29403392
Complex modulation using tandem polarization modulators
NASA Astrophysics Data System (ADS)
Hasan, Mehedi; Hall, Trevor
2017-11-01
A novel photonic technique for implementing frequency up-conversion or complex modulation is proposed. The proposed circuit consists of a sandwich of a quarter-wave plate between two polarization modulators, driven, respectively, by an in-phase and quadrature-phase signals. The operation of the circuit is modelled using a transmission matrix method. The theoretical prediction is then validated by simulation using an industry-standard software tool. The intrinsic conversion efficiency of the architecture is improved by 6 dB over a functionally equivalent design based on dual parallel Mach-Zehnder modulators. Non-ideal scenarios such as imperfect alignment of the optical components and power imbalances and phase errors in the electric drive signals are also analysed. As light travels, along one physical path, the proposed design can be implemented using discrete components with greater control of relative optical path length differences. The circuit can further be integrated in any material platform that offers electro-optic polarization modulators.
How music alters a kiss: superior temporal gyrus controls fusiform-amygdalar effective connectivity.
Pehrs, Corinna; Deserno, Lorenz; Bakels, Jan-Hendrik; Schlochtermeier, Lorna H; Kappelhoff, Hermann; Jacobs, Arthur M; Fritz, Thomas Hans; Koelsch, Stefan; Kuchinke, Lars
2014-11-01
While watching movies, the brain integrates the visual information and the musical soundtrack into a coherent percept. Multisensory integration can lead to emotion elicitation on which soundtrack valences may have a modulatory impact. Here, dynamic kissing scenes from romantic comedies were presented to 22 participants (13 females) during functional magnetic resonance imaging scanning. The kissing scenes were either accompanied by happy music, sad music or no music. Evidence from cross-modal studies motivated a predefined three-region network for multisensory integration of emotion, consisting of fusiform gyrus (FG), amygdala (AMY) and anterior superior temporal gyrus (aSTG). The interactions in this network were investigated using dynamic causal models of effective connectivity. This revealed bilinear modulations by happy and sad music with suppression effects on the connectivity from FG and AMY to aSTG. Non-linear dynamic causal modeling showed a suppressive gating effect of aSTG on fusiform-amygdalar connectivity. In conclusion, fusiform to amygdala coupling strength is modulated via feedback through aSTG as region for multisensory integration of emotional material. This mechanism was emotion-specific and more pronounced for sad music. Therefore, soundtrack valences may modulate emotion elicitation in movies by differentially changing preprocessed visual information to the amygdala. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
How music alters a kiss: superior temporal gyrus controls fusiform–amygdalar effective connectivity
Deserno, Lorenz; Bakels, Jan-Hendrik; Schlochtermeier, Lorna H.; Kappelhoff, Hermann; Jacobs, Arthur M.; Fritz, Thomas Hans; Koelsch, Stefan; Kuchinke, Lars
2014-01-01
While watching movies, the brain integrates the visual information and the musical soundtrack into a coherent percept. Multisensory integration can lead to emotion elicitation on which soundtrack valences may have a modulatory impact. Here, dynamic kissing scenes from romantic comedies were presented to 22 participants (13 females) during functional magnetic resonance imaging scanning. The kissing scenes were either accompanied by happy music, sad music or no music. Evidence from cross-modal studies motivated a predefined three-region network for multisensory integration of emotion, consisting of fusiform gyrus (FG), amygdala (AMY) and anterior superior temporal gyrus (aSTG). The interactions in this network were investigated using dynamic causal models of effective connectivity. This revealed bilinear modulations by happy and sad music with suppression effects on the connectivity from FG and AMY to aSTG. Non-linear dynamic causal modeling showed a suppressive gating effect of aSTG on fusiform–amygdalar connectivity. In conclusion, fusiform to amygdala coupling strength is modulated via feedback through aSTG as region for multisensory integration of emotional material. This mechanism was emotion-specific and more pronounced for sad music. Therefore, soundtrack valences may modulate emotion elicitation in movies by differentially changing preprocessed visual information to the amygdala. PMID:24298171
Low work function materials for microminiature energy conversion and recovery applications
Zavadil, Kevin R.; Ruffner, Judith A.; King, Donald B.
2003-05-13
Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties. In the preferred embodiment, the individual layers include mixed BaSrCaO, scandium oxide and tungsten.
Dynamically Reconfigurable Metadevice Employing Nanostructured Phase-Change Materials
Zhu, Zhihua; Evans, Philip G.; Haglund, Richard F.; ...
2017-07-21
Mastering dynamic free-space spectral control and modulation in the near-infrared (NIR) and optical regimes remains a challenging task that is hindered by the available functional materials at high frequencies. In this work, we have realized an efficient metadevice capable of spectral control by minimizing the thermal mass of a vanadium dioxide phase-change material (PCM) and placing the PCM at the feed gap of a bow-tie field antenna. The device has an experimentally measured tuning range of up to 360 nm in the NIR and a modulation depth of 33% at the resonant wavelength. The metadevice is configured for integrated andmore » local heating, leading to faster switching and more precise spatial control compared with devices based on phase-change thin films. We envisage that the combined advantages of this device will open new opportunities for signal processing, memory, security, and holography at optical frequencies.« less
Dynamically Reconfigurable Metadevice Employing Nanostructured Phase-Change Materials.
Zhu, Zhihua; Evans, Philip G; Haglund, Richard F; Valentine, Jason G
2017-08-09
Mastering dynamic free-space spectral control and modulation in the near-infrared (NIR) and optical regimes remains a challenging task that is hindered by the available functional materials at high frequencies. In this work, we have realized an efficient metadevice capable of spectral control by minimizing the thermal mass of a vanadium dioxide phase-change material (PCM) and placing the PCM at the feed gap of a bow-tie field antenna. The device has an experimentally measured tuning range of up to 360 nm in the NIR and a modulation depth of 33% at the resonant wavelength. The metadevice is configured for integrated and local heating, leading to faster switching and more precise spatial control compared with devices based on phase-change thin films. We envisage that the combined advantages of this device will open new opportunities for signal processing, memory, security, and holography at optical frequencies.
Koontz, Nicholas A; Gunderman, Richard B
2012-04-01
This study assesses the effect on medical student understanding of a new radiobiology and radiation safety module in a fourth-year radiology clerkship. A dedicated radiobiology and radiation safety module was incorporated into the fourth-year medical school radiology clerkship at our institution. Student understanding of the material was assessed via pretest and posttest. Statistical analysis was performed to assess significance of changes in student performance. In addition, we surveyed student perceptions of the importance of this material in medical education and practice. Monthly pretest mean scores ranged from 47.8% to 55.6%, with an average monthly pretest score of 50.3%. Monthly posttest mean scores ranged from 77.3% to 91.2%, with an average monthly posttest score of 83.9%. The improvement in exam scores after the educational intervention was statistically significant (all P < .01). The introduction of a new educational module can significantly improve medical student understanding of radiobiology and radiation safety. Copyright © 2012 AUR. Published by Elsevier Inc. All rights reserved.
Integrated learning in dentistry: baseline data and first evaluation at the Dental School of Basel.
Neuhaus, K W; Schegg, R; Krastl, G; Amato, M; Weiger, R; Walter, C
2008-08-01
Integrated learning modules were introduced and baseline information was collected, in order to identify the expectations regarding e-learning. Furthermore, first formative evaluation of fourth-year dental students was conducted and the experience gained with summative online assessment was reported. Questionnaires designed by Infratest dimap (Berlin, Germany) were distributed to undergraduate students (n = 72) of the School of Dentistry. The fourth-year dental students went through a preliminary evaluation process. An online test was evaluated and compared with a traditional examination. Sixty-three questionnaires were returned. Sixty-five per cent of the students were already familiar with e-learning. All but one student owned at least one personal computer or laptop. Ninety-one per cent of the students expected positive effects from the integration of online modules. Enhanced flexibility regarding time and location as well as comfortable access to learning materials were mentioned most frequently. Ninety per cent of the students expected to achieve better results by finding it easier to understand learning materials produced with multimedia tools. Sixty per cent of the students feared technical complications when using an online platform. The online test was successfully performed. A formative evaluation process demonstrated agreement between expectations and first experiences with e-learning. Most students expect the quality of their studies to improve by implementation of e-learning. Students appreciating regularly updated learning materials particularly emphasise the importance of its visualisation. Online tests might be an option for student's self-performance rating.
Integration of ZnO and CuO nanowires into a thermoelectric module
Dalola, Simone; Faglia, Guido; Comini, Elisabetta; Ferroni, Matteo; Soldano, Caterina; Ferrari, Vittorio; Sberveglieri, Giorgio
2014-01-01
Summary Zinc oxide (ZnO, n-type) and copper oxide (CuO, p-type) nanowires have been synthesized and preliminarily investigated as innovative materials for the fabrication of a proof-of-concept thermoelectric device. The Seebeck coefficients, electrical conductivity and thermoelectric power factors (TPF) of both semiconductor materials have been determined independently using a custom experimental set-up, leading to results in agreement with available literature with potential improvement. Combining bundles of ZnO and CuO nanowires in a series of five thermocouples on alumina leads to a macroscopic prototype of a planar thermoelectric generator (TEG) unit. This demonstrates the possibility of further integration of metal oxide nanostructures into efficient thermoelectric devices. PMID:24991531
Integration of ZnO and CuO nanowires into a thermoelectric module.
Zappa, Dario; Dalola, Simone; Faglia, Guido; Comini, Elisabetta; Ferroni, Matteo; Soldano, Caterina; Ferrari, Vittorio; Sberveglieri, Giorgio
2014-01-01
Zinc oxide (ZnO, n-type) and copper oxide (CuO, p-type) nanowires have been synthesized and preliminarily investigated as innovative materials for the fabrication of a proof-of-concept thermoelectric device. The Seebeck coefficients, electrical conductivity and thermoelectric power factors (TPF) of both semiconductor materials have been determined independently using a custom experimental set-up, leading to results in agreement with available literature with potential improvement. Combining bundles of ZnO and CuO nanowires in a series of five thermocouples on alumina leads to a macroscopic prototype of a planar thermoelectric generator (TEG) unit. This demonstrates the possibility of further integration of metal oxide nanostructures into efficient thermoelectric devices.
Gigahertz speed operation of epsilon-near-zero silicon photonic modulators
Wood, Michael G.; Campione, Salvatore; Parameswaran, S.; ...
2018-02-21
Opmore » tical communication systems increasingly require electro-optical modulators that deliver high modulation speeds across a large optical bandwidth with a small device footprint and a CMOS-compatible fabrication process. Although silicon photonic modulators based on transparent conducting oxides (TCOs) have shown promise for delivering on these requirements, modulation speeds to date have been limited. Here, we describe the design, fabrication, and performance of a fast, compact electroabsorption modulator based on TCOs. The modulator works by using bias voltage to increase the carrier density in the conducting oxide, which changes the permittivity and hence optical attenuation by almost 10 dB. Under bias, light is tightly confined to the conducting oxide layer through nonresonant epsilon-near-zero (ENZ) effects, which enable modulation over a broad range of wavelengths in the telecommunications band. Our approach features simple integration with passive silicon waveguides, the use of stable inorganic materials, and the ability to modulate both transverse electric and magnetic polarizations with the same device design. Using a 4-μm-long modulator and a drive voltage of 2 V p p , we demonstrate digital modulation at rates of 2.5 Gb/s. We report broadband operation with a 6.5 dB extinction ratio across the 1530–1590 nm band and a 10 dB insertion loss. This work verifies that high-speed ENZ devices can be created using conducting oxide materials and paves the way for additional technology development that could have a broad impact on future optical communications systems.« less
Gigahertz speed operation of epsilon-near-zero silicon photonic modulators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Michael G.; Campione, Salvatore; Parameswaran, S.
Opmore » tical communication systems increasingly require electro-optical modulators that deliver high modulation speeds across a large optical bandwidth with a small device footprint and a CMOS-compatible fabrication process. Although silicon photonic modulators based on transparent conducting oxides (TCOs) have shown promise for delivering on these requirements, modulation speeds to date have been limited. Here, we describe the design, fabrication, and performance of a fast, compact electroabsorption modulator based on TCOs. The modulator works by using bias voltage to increase the carrier density in the conducting oxide, which changes the permittivity and hence optical attenuation by almost 10 dB. Under bias, light is tightly confined to the conducting oxide layer through nonresonant epsilon-near-zero (ENZ) effects, which enable modulation over a broad range of wavelengths in the telecommunications band. Our approach features simple integration with passive silicon waveguides, the use of stable inorganic materials, and the ability to modulate both transverse electric and magnetic polarizations with the same device design. Using a 4-μm-long modulator and a drive voltage of 2 V p p , we demonstrate digital modulation at rates of 2.5 Gb/s. We report broadband operation with a 6.5 dB extinction ratio across the 1530–1590 nm band and a 10 dB insertion loss. This work verifies that high-speed ENZ devices can be created using conducting oxide materials and paves the way for additional technology development that could have a broad impact on future optical communications systems.« less
Very-low-power and footprint integrated photonic modulators and switches for ICT
NASA Astrophysics Data System (ADS)
Thylén, Lars; Holmström, Petter; Wosinski, Lech
2013-03-01
The current development in photonics for communications and interconnects pose increasing requirements on reduction of footprint, power dissipation and cost, as well as increased bandwidth. Integrated nanophotonics has been viewed as one solution to this, capitalizing on development in nanotechnology as such as well as on increased insights into light matter interaction on the nanoscale. The latter can be exemplified by plasmonics and low-dimensional semiconductors such as quantum dots (QDs). In this scenario the development of better electrooptic materials is also of great importance, the electrooptic polymers being an example, since they potentially offer improved properties for optical phase modulators in terms of power and probably cost and general flexibility. Phase modulators are essential for e.g. the rapidly developing advanced modulation formats for telecom, since phase modulation basically can generate any type of modulation. The electrooptic polymers, e.g. in combination with plasmonics nanoparticle array waveguides or nanostructured hybrid plasmonic media can theoretically give extremely compact and low power dissipation modulators, still to be demonstrated. The low-dimensional semiconductors, e.g. in the shape of QDs, can be employed for modulation or switching functions, offering possibilities in the future for scaling to 2 or 3 dimensions for advanced switching functions. In both the plasmonics and QD cases, nanosizing and low power dissipation are generally due to near-field interactions, albeit being of different physical origin in the two cases. A comparison of all-optical and electronically controlled switching is given.
Robust, Rework-able Thermal Electronic Packaging: Applications in High Power TR Modules for Space
NASA Technical Reports Server (NTRS)
Hoffman, James Patrick; Del Castillo, Linda; Hunter, Don; Miller, Jennifer
2012-01-01
The higher output power densities required of modern radar architectures, such as the proposed DESDynI [Deformation, Ecosystem Structure, and Dynamics of Ice] SAR [Synthetic Aperture Radar] Instrument (or DSI) require increasingly dense high power electronics. To enable these higher power densities, while maintaining or even improving hardware reliability, requires improvements in integrating advanced thermal packaging technologies into radar transmit/receive (TR) modules. New materials and techniques have been studied and are now being implemented side-by-side with more standard technology typically used in flight hardware.
Periosteum mechanobiology and mechanistic insights for regenerative medicine
Knothe Tate, Melissa L; Yu, Nicole Y C; Jalilian, Iman; Pereira, André F; Knothe, Ulf R
2016-01-01
Periosteum is a smart mechanobiological material that serves as a habitat and delivery vehicle for stem cells as well as biological factors that modulate tissue genesis and healing. Periosteum's remarkable regenerative capacity has been harnessed clinically for over two hundred years. Scientific studies over the past decade have begun to decipher the mechanobiology of periosteum, which has a significant role in its regenerative capacity. This integrative review outlines recent mechanobiological insights that are key to modulating and translating periosteum and its resident stem cells in a regenerative medicine context. PMID:27974968
Electroabsorption-modulated widely tunable DBR laser transmitter for WDM-PONs.
Han, Liangshun; Liang, Song; Wang, Huitao; Qiao, Lijun; Xu, Junjie; Zhao, Lingjuan; Zhu, Hongliang; Wang, Baojun; Wang, Wei
2014-12-01
We present an InP based distributed Bragg reflector (DBR) laser transmitter which has a wide wavelength tuning range and a high chip output power for wavelength division multiplexing passive optical network (WDM-PON) applications. By butt-jointing InGaAsP with 1.45 µm emission wavelength as the material of the grating section, the laser wavelength can be tuned for over 13 nm by the DBR current. Accompanied by varying the chip temperature, the tuning range can be further enlarged to 16 nm. With the help of the integrated semiconductor optical amplifier (SOA), the largest chip output power is over 30 mW. The electroabsorption modulator (EAM) is integrated into the device by the selective-area growth (SAG) technique. The 3 dB small signal modulation bandwidth of the EAM is over 13 GHz. The device has both a simple tuning scheme and a simple fabrication procedure, making it suitable for low cost massive production which is desirable for WDM-PON uses.
Nanometric holograms based on a topological insulator material.
Yue, Zengji; Xue, Gaolei; Liu, Juan; Wang, Yongtian; Gu, Min
2017-05-18
Holography has extremely extensive applications in conventional optical instruments spanning optical microscopy and imaging, three-dimensional displays and metrology. To integrate holography with modern low-dimensional electronic devices, holograms need to be thinned to a nanometric scale. However, to keep a pronounced phase shift modulation, the thickness of holograms has been generally limited to the optical wavelength scale, which hinders their integration with ultrathin electronic devices. Here, we break this limit and achieve 60 nm holograms using a topological insulator material. We discover that nanometric topological insulator thin films act as an intrinsic optical resonant cavity due to the unequal refractive indices in their metallic surfaces and bulk. The resonant cavity leads to enhancement of phase shifts and thus the holographic imaging. Our work paves a way towards integrating holography with flat electronic devices for optical imaging, data storage and information security.
Hybrid integration of carbon nanotubes in silicon photonic structures
NASA Astrophysics Data System (ADS)
Durán-Valdeiglesias, E.; Zhang, W.; Alonso-Ramos, C.; Le Roux, X.; Serna, S.; Hoang, H. C.; Marris-Morini, D.; Cassan, E.; Intonti, F.; Sarti, F.; Caselli, N.; La China, F.; Gurioli, M.; Balestrieri, M.; Vivien, L.; Filoramo, A.
2017-02-01
Silicon photonics, due to its compatibility with the CMOS platform and unprecedented integration capability, has become the preferred solution for the implementation of next generation optical interconnects to accomplish high efficiency, low energy consumption, low cost and device miniaturization in one single chip. However, it is restricted by silicon itself. Silicon does not have efficient light emission or detection in the telecommunication wavelength range (1.3 μm-1.5 μm) or any electro-optic effect (i.e. Pockels effect). Hence, silicon photonic needs to be complemented with other materials for the realization of optically-active devices, including III-V for lasing and Ge for detection. The very different requirement of these materials results in complex fabrication processes that offset the cost-effectiveness of the Si photonics approach. For this purpose, carbon nanotubes (CNTs) have recently been proposed as an attractive one-dimensional light emitting material. Interestingly, semiconducting single walled CNTs (SWNTs) exhibit room-temperature photo- and electro-luminescence in the near-IR that could be exploited for the implementation of integrated nano-sources. They can also be considered for the realization of photo-detectors and optical modulators, since they rely on intrinsically fast non-linear effects, such as Stark and Kerr effect. All these properties make SWNTs ideal candidates in order to fabricate a large variety of optoelectronic devices, including near-IR sources, modulators and photodetectors on Si photonic platforms. In addition, solution processed SWNTs can be integrated on Si using spin-coating or drop-casting techniques, obviating the need of complex epitaxial growth or chip bonding approaches. Here, we report on our recent progress in the coupling of SWNTs light emission into optical resonators implemented on the silicon-on-insulator (SOI) platform. .
Conaway, Mark A; Schroeder, Lauren; von Cramon-Taubadel, Noreen
2018-03-22
Integration and modularity reflect the coordinated action of past evolutionary processes and, in turn, constrain or facilitate phenotypic evolvability. Here, we analyze magnitudes of integration in the macaque postcranium to test whether 20 a priori defined modules are (1) more tightly integrated than random sets of postcranial traits, and (2) are differentiated based on mode of definition, with developmental modules expected to be more integrated than functional or anatomical modules. The 3D morphometric data collected for eight limb and girdle bones for 60 macaques were collated into anatomical, developmental, and functional modules. A resampling technique was used to create random samples of integration values for each module for statistical comparison. Our results found that not all a priori defined modules were more strongly integrated than random samples of postcranial traits and that specific types of modules did not present consistent patterns of integration. Rather, girdle and joint modules were consistently less integrated than limb modules, and forelimb elements were less integrated than hindlimbs. The results suggest that morphometrically complex modules tend to be less integrated than simple limb bones, irrespective of the number of available traits. However, differences in integration of the fore- and hindlimb more likely reflects the multitude of locomotory, feeding, and social functions involved. It remains to be tested whether patterns of integration identified here are primate universals, and to what extent they vary depending on phylogenetic or functional factors. © 2018 Wiley Periodicals, Inc.
1997-01-01
The 11-day training course on integrated management of childhood illness was field tested with three types of first-level facility health workers: medical assistants, rural medical aides, and MCH (maternal and child health) aides. The objective of the field test was to determine whether the materials were effective in preparing participants to manage correctly sick children and to suggest improvements in the course materials and teaching procedures. The course combined classroom work and daily inpatient and outpatient clinical sessions. Each participant individually examined 9-10 inpatients and managed more than 30 sick children as outpatients. Individual feedback from facilitators during clinical practice and module work, combined with data collection documenting the adequacy of the assessment, classification, treatment and counselling carried out by the participants, allowed an assessment of the participants' mastery of key clinical skills. Although some participants had difficulty in reading the modules in English, all three groups overall were able to assess, classify, and treat most sick children by the end of the course, and most of them were able to provide adequate counselling. Specific improvements were suggested and subsequently incorporated into the guidelines and training materials. PMID:9529718
Crystalline-silicon reliability lessons for thin-film modules
NASA Technical Reports Server (NTRS)
Ross, R. G., Jr.
1985-01-01
The reliability of crystalline silicon modules has been brought to a high level with lifetimes approaching 20 years, and excellent industry credibility and user satisfaction. The transition from crystalline modules to thin film modules is comparable to the transition from discrete transistors to integrated circuits. New cell materials and monolithic structures will require new device processing techniques, but the package function and design will evolve to a lesser extent. Although there will be new encapsulants optimized to take advantage of the mechanical flexibility and low temperature processing features of thin films, the reliability and life degradation stresses and mechanisms will remain mostly unchanged. Key reliability technologies in common between crystalline and thin film modules include hot spot heating, galvanic and electrochemical corrosion, hail impact stresses, glass breakage, mechanical fatigue, photothermal degradation of encapsulants, operating temperature, moisture sorption, circuit design strategies, product safety issues, and the process required to achieve a reliable product from a laboratory prototype.
Modelling of polymer photodegradation for solar cell modules
NASA Technical Reports Server (NTRS)
Somersall, A. C.; Guillet, J. E.
1981-01-01
A computer model including an integration routine was developed and demonstrated to simulate, in principle, the chemical changes which may occur in the photooxidation of hydrocarbons, using as input data a set of elementary reactions, corresponding rate constants and appropriate starting conditions. Application of this model to the photooxidation of pottant and plastic materials used in the LSA module designs provides a reliable predictive capability regarding the useful lifetime of these materials. An earlier mechanism consisting of 46 reactions was simplified considerably by reducing the number of formal termination steps since it became apparent that the major termination process goes via the peroxy radicals. In addition, new reactions of oxygen with acryl radicals (from Norrish type I) to form peracids, which then decompose to form carbon dioxide are included.
NASA Technical Reports Server (NTRS)
Prasad, Narashimha S.; Taylor, Patrick J.; Trivedi, Sudhir B.; Kutcher, Susan
2010-01-01
We report the results of fabrication and testing of a thermoelectric power generation module. The module was fabricated using a new "flip-chip" module assembly technique that is scalable and modular. This technique results in a low value of contact resistivity ( < or = 10(exp 5) Ohms-sq cm). It can be used to leverage new advances in thin-film and nanostructured materials for the fabrication of new miniature thermoelectric devices. It may also enable monolithic integration of large devices or tandem arrays of devices on flexible or curved surfaces. Under mild testing, a power of 22 mW/sq cm was obtained from small (<100 K) temperature differences. At higher, more realistic temperature differences, approx.500 K, where the efficiency of these materials greatly improves, this power density would scale to between 0.5 and 1 Watt/cm2. These results highlight the excellent potential for the generation and scavenging of electrical power of practical and usable magnitude for remote applications using thermoelectric power generation technologies.
2016-04-01
the failure process of photovoltaic ( PV ) amorphous Si thin film solar cells using commercial solar cell modules PT15-300 manufactured by Iowa Thin...this research project and the results and conclusions. This research program focused on the mechanics of materials employed in thin film solar cells...experimental results and references are provided to publications for further details. 1. MECHANICAL DURABILITY OF THIN FILM SI SOLAR CELLS We investigated
Gamma motes for detection of radioactive materials in shipping containers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harold McHugh; William Quam; Stephan Weeks
Shipping containers can be effectively monitored for radiological materials using gamma (and neutron) motes in distributed mesh networks. The mote platform is ideal for collecting data for integration into operational management systems required for efficiently and transparently monitoring international trade. Significant reductions in size and power requirements have been achieved for room-temperature cadmium zinc telluride (CZT) gamma detectors. Miniaturization of radio modules and microcontroller units are paving the way for low-power, deeply-embedded, wireless sensor distributed mesh networks.
Cryo Testing of tbe James Webb Space Telescope's Integrated Science Instrument Module
NASA Technical Reports Server (NTRS)
VanCampen, Julie
2004-01-01
The Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope will be integrated and tested at the Environmental Test Facilities at Goddard Space Flight Center (GSFC). The cryogenic thermal vacuum testing of the ISIM will be the most difficult and problematic portion of the GSFC Integration and Test flow. The test is to validate the coupled interface of the science instruments and the ISIM structure and to sufficiently stress that interface while validating image quality of the science instruments. The instruments and the structure are not made from the same materials and have different CTE. Test objectives and verification rationale are currently being evaluated in Phase B of the project plan. The test program will encounter engineering challenges and limitations, which are derived by cost and technology many of which can be mitigated by facility upgrades, creative GSE, and thorough forethought. The cryogenic testing of the ISIM will involve a number of risks such as the implementation of unique metrology techniques, mechanical, electrical and optical simulators housed within the cryogenic vacuum environment. These potential risks are investigated and possible solutions are proposed.
NASA Astrophysics Data System (ADS)
Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya
2015-04-01
A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed. Broadband QD optical gain material was used to achieve Gbps-order high-speed optical data transmission, and an optical gain change as high as approximately 6-7 dB was obtained with a low OGM voltage of 2.0 V. Loss of optical power due to insertion of the device was also effectively compensated for by the SOA section. Furthermore, it was confirmed that the QD-OGM/SOA device helped achieve 6.0-Gbps error-free optical data transmission over a 2.0-km-long photonic crystal fiber. We also successfully demonstrated generation of Gbps-order, high-speed, and error-free optical signals in the >5.5-THz broadband optical frequency bandwidth larger than the C-band. These results suggest that the developed monolithically integrated QD-OGM/SOA device will be an advantageous and compact means of increasing the usable optical frequency channels for short-reach communications.
Magnetic-free non-reciprocity based on staggered commutation
Reiskarimian, Negar; Krishnaswamy, Harish
2016-01-01
Lorentz reciprocity is a fundamental characteristic of the vast majority of electronic and photonic structures. However, non-reciprocal components such as isolators, circulators and gyrators enable new applications ranging from radio frequencies to optical frequencies, including full-duplex wireless communication and on-chip all-optical information processing. Such components today dominantly rely on the phenomenon of Faraday rotation in magneto-optic materials. However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit. Here we demonstrate magnetic-free linear passive non-reciprocity based on the concept of staggered commutation. Commutation is a form of parametric modulation with very high modulation ratio. We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal–oxide–semiconductor integrated circuit for the first time. PMID:27079524
NASA Astrophysics Data System (ADS)
Tsuru, Daigo; Tanigawa, Hisashi; Hirose, Takanori; Mohri, Kensuke; Seki, Yohji; Enoeda, Mikio; Ezato, Koichiro; Suzuki, Satoshi; Nishi, Hiroshi; Akiba, Masato
2009-06-01
As the primary candidate of ITER Test Blanket Module (TBM) to be tested under the leadership of Japan, a water cooled solid breeder (WCSB) TBM is being developed. This paper shows the recent achievements towards the milestones of ITER TBMs prior to the installation, which consist of design integration in ITER, module qualification and safety assessment. With respect to the design integration, targeting the detailed design final report in 2012, structure designs of the WCSB TBM and the interfacing components (common frame and backside shielding) that are placed in a test port of ITER and the layout of the cooling system are presented. As for the module qualification, a real-scale first wall mock-up fabricated by using the hot isostatic pressing method by structural material of reduced activation martensitic ferritic steel, F82H, and flow and irradiation test of the mock-up are presented. As for safety milestones, the contents of the preliminary safety report in 2008 consisting of source term identification, failure mode and effect analysis (FMEA) and identification of postulated initiating events (PIEs) and safety analyses are presented.
ERIC Educational Resources Information Center
Sung, K.; Hillyard, C.; Angotti, R. L.; Panitz, M. W.; Goldstein, D. S.; Nordlinger, J.
2011-01-01
Despite the proven success of using computer video games as a context for teaching introductory programming (CS1/2) courses, barriers including the lack of adoptable materials, required background expertise (in graphics/games), and institutional acceptance still prevent interested faculty members from experimenting with this approach. Game-themed…
2017-10-12
iss053e098185 (Oct. 12, 2017) --- Flight Engineer Paolo Nespoli works inside the Harmony module to configure the Combustion Integrated Rack and enable the Advanced Combustion Microgravity Experiment (ACME). The primary and secondary goals of ACME are the improved fuel efficiency and reduced pollutant production in practical combustion on Earth, and spacecraft fire prevention through innovative research focused on materials flammability.
Nanometric holograms based on a topological insulator material
Yue, Zengji; Xue, Gaolei; Liu, Juan; Wang, Yongtian; Gu, Min
2017-01-01
Holography has extremely extensive applications in conventional optical instruments spanning optical microscopy and imaging, three-dimensional displays and metrology. To integrate holography with modern low-dimensional electronic devices, holograms need to be thinned to a nanometric scale. However, to keep a pronounced phase shift modulation, the thickness of holograms has been generally limited to the optical wavelength scale, which hinders their integration with ultrathin electronic devices. Here, we break this limit and achieve 60 nm holograms using a topological insulator material. We discover that nanometric topological insulator thin films act as an intrinsic optical resonant cavity due to the unequal refractive indices in their metallic surfaces and bulk. The resonant cavity leads to enhancement of phase shifts and thus the holographic imaging. Our work paves a way towards integrating holography with flat electronic devices for optical imaging, data storage and information security. PMID:28516906
2010-01-01
Background The modular approach to analysis of genetically modified organisms (GMOs) relies on the independence of the modules combined (i.e. DNA extraction and GM quantification). The validity of this assumption has to be proved on the basis of specific performance criteria. Results An experiment was conducted using, as a reference, the validated quantitative real-time polymerase chain reaction (PCR) module for detection of glyphosate-tolerant Roundup Ready® GM soybean (RRS). Different DNA extraction modules (CTAB, Wizard and Dellaporta), were used to extract DNA from different food/feed matrices (feed, biscuit and certified reference material [CRM 1%]) containing the target of the real-time PCR module used for validation. Purity and structural integrity (absence of inhibition) were used as basic criteria that a DNA extraction module must satisfy in order to provide suitable template DNA for quantitative real-time (RT) PCR-based GMO analysis. When performance criteria were applied (removal of non-compliant DNA extracts), the independence of GMO quantification from the extraction method and matrix was statistically proved, except in the case of Wizard applied to biscuit. A fuzzy logic-based procedure also confirmed the relatively poor performance of the Wizard/biscuit combination. Conclusions For RRS, this study recognises that modularity can be generally accepted, with the limitation of avoiding combining highly processed material (i.e. biscuit) with a magnetic-beads system (i.e. Wizard). PMID:20687918
NASA welding assessment program
NASA Technical Reports Server (NTRS)
Stofel, E. J.
1984-01-01
A long duration test was conducted for comparing various methods of attaching electrical interconnects to solar cells for near Earth orbit spacecraft. Representative solar array modules were thermally cycled for 36,000 cycles between -80 and +80 C. The environmental stress of more than 6 years on a near Earth spacecraft as it cycles in and out of the earth's shadow was simulated. Evaluations of the integrity of these modules were made by visual and by electrical examinations before starting the cycling and then at periodic intervals during the cycling tests. Modules included examples of parallel gap and of ultrasonic welding, as well as soldering. The materials and fabrication processes are state of the art, suitable for forming large solar arrays of spacecraft quality. The modules survived this extensive cycling without detectable degradation in their ability to generate power under sunlight illumination.
Photovoltaic module and module arrays
Botkin, Jonathan; Graves, Simon; Lenox, Carl J. S.; Culligan, Matthew; Danning, Matt
2013-08-27
A photovoltaic (PV) module including a PV device and a frame, The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.
Photovoltaic module and module arrays
Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Lenox, Carl J. S. [Oakland, CA; Culligan, Matthew [Berkeley, CA; Danning, Matt [Oakland, CA
2012-07-17
A photovoltaic (PV) module including a PV device and a frame. The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.
Topics in electrochemical degradation of photovoltaic modules
NASA Technical Reports Server (NTRS)
Mon, G. R.
1984-01-01
Electrochemical degradation of photovoltaic modules was examined. It is found that the extent of electrochemical damage is dependent on the integrated leakage current. The PV electrochemical degradation mechanisms in the two polarities are different: (1) degradation rates in the two polarities are of the same order of magnitude; (2) center tapped grounded arrays are a preferred system configuration to minimize electrochemical degradation. The use of thicker pottant layers and polymer substrate films to reduce equilibrium leakage current values is suggested. A metallized substrate layer, if used, should be isolated from the pottant and the frame by polyester layers, and EVA modules appear to be consistent with 30 year life allocation levels for electrochemical damage. Temperature acceleration factors are well behaved and moderately well understood; humidity acceleration factors vary radically with module construction and materials and require additional research.
Chung, Haejun; Sun, Xingshu; Mohite, Aditya D; Singh, Rahul; Kumar, Lokendra; Alam, Muhammad A; Bermel, Peter
2017-04-17
A key challenge in photovoltaics today is to develop cell technologies with both higher efficiencies and lower fabrication costs than incumbent crystalline silicon (c-Si) single-junction cells. While tandem cells have higher efficiencies than c-Si alone, it is generally challenging to find a low-cost, high-performance material to pair with c-Si. However, the recent emergence of 22% efficient perovskite photovoltaics has created a tremendous opportunity for high-performance, low-cost perovskite / crystalline silicon tandem photovoltaic cells. Nonetheless, two key challenges remain. First, integrating perovskites into tandem structures has not yet been demonstrated to yield performance exceeding commercially available crystalline silicon modules. Second, the stability of perovskites is inconsistent with the needs of most end-users, who install photovoltaic modules to produce power for 25 years or more. Making these cells viable thus requires innovation in materials processing, device design, fabrication, and yield. We will address these two gaps in the photovoltaic literature by investigating new types of 2D perovskite materials with n-butylammonium spacer layers, and integrating these materials into bifacial tandem solar cells providing at least 30% normalized power production. We find that an optimized 2D perovskite ((BA)2(MA)3(Sn0.6Pb0.4)4I13)/silicon bifacial tandem cell, given a globally average albedo of 30%, yields a normalized power production of 30.31%, which should be stable for extended time periods without further change in materials or encapsulation.
Advances in Materials for Recent Low-Profile Implantable Bioelectronics.
Chen, Yanfei; Kim, Yun-Soung; Tillman, Bryan W; Yeo, Woon-Hong; Chun, Youngjae
2018-03-29
The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material's property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities.
NASA Technical Reports Server (NTRS)
1988-01-01
Martin Marietta Aero and Naval Systems has advanced the CAD art to a very high level at its Robotics Laboratory. One of the company's major projects is construction of a huge Field Material Handling Robot for the Army's Human Engineering Lab. Design of FMR, intended to move heavy and dangerous material such as ammunition, was a triumph in CAD Engineering. Separate computer problems modeled the robot's kinematics and dynamics, yielding such parameters as the strength of materials required for each component, the length of the arms, their degree of freedom and power of hydraulic system needed. The Robotics Lab went a step further and added data enabling computer simulation and animation of the robot's total operational capability under various loading and unloading conditions. NASA computer program (IAC), integrated Analysis Capability Engineering Database was used. Program contains a series of modules that can stand alone or be integrated with data from sensors or software tools.
A MoTe2-based light-emitting diode and photodetector for silicon photonic integrated circuits.
Bie, Ya-Qing; Grosso, Gabriele; Heuck, Mikkel; Furchi, Marco M; Cao, Yuan; Zheng, Jiabao; Bunandar, Darius; Navarro-Moratalla, Efren; Zhou, Lin; Efetov, Dmitri K; Taniguchi, Takashi; Watanabe, Kenji; Kong, Jing; Englund, Dirk; Jarillo-Herrero, Pablo
2017-12-01
One of the current challenges in photonics is developing high-speed, power-efficient, chip-integrated optical communications devices to address the interconnects bottleneck in high-speed computing systems. Silicon photonics has emerged as a leading architecture, in part because of the promise that many components, such as waveguides, couplers, interferometers and modulators, could be directly integrated on silicon-based processors. However, light sources and photodetectors present ongoing challenges. Common approaches for light sources include one or few off-chip or wafer-bonded lasers based on III-V materials, but recent system architecture studies show advantages for the use of many directly modulated light sources positioned at the transmitter location. The most advanced photodetectors in the silicon photonic process are based on germanium, but this requires additional germanium growth, which increases the system cost. The emerging two-dimensional transition-metal dichalcogenides (TMDs) offer a path for optical interconnect components that can be integrated with silicon photonics and complementary metal-oxide-semiconductors (CMOS) processing by back-end-of-the-line steps. Here, we demonstrate a silicon waveguide-integrated light source and photodetector based on a p-n junction of bilayer MoTe 2 , a TMD semiconductor with an infrared bandgap. This state-of-the-art fabrication technology provides new opportunities for integrated optoelectronic systems.
A MoTe2-based light-emitting diode and photodetector for silicon photonic integrated circuits
NASA Astrophysics Data System (ADS)
Bie, Ya-Qing; Grosso, Gabriele; Heuck, Mikkel; Furchi, Marco M.; Cao, Yuan; Zheng, Jiabao; Bunandar, Darius; Navarro-Moratalla, Efren; Zhou, Lin; Efetov, Dmitri K.; Taniguchi, Takashi; Watanabe, Kenji; Kong, Jing; Englund, Dirk; Jarillo-Herrero, Pablo
2017-12-01
One of the current challenges in photonics is developing high-speed, power-efficient, chip-integrated optical communications devices to address the interconnects bottleneck in high-speed computing systems. Silicon photonics has emerged as a leading architecture, in part because of the promise that many components, such as waveguides, couplers, interferometers and modulators, could be directly integrated on silicon-based processors. However, light sources and photodetectors present ongoing challenges. Common approaches for light sources include one or few off-chip or wafer-bonded lasers based on III-V materials, but recent system architecture studies show advantages for the use of many directly modulated light sources positioned at the transmitter location. The most advanced photodetectors in the silicon photonic process are based on germanium, but this requires additional germanium growth, which increases the system cost. The emerging two-dimensional transition-metal dichalcogenides (TMDs) offer a path for optical interconnect components that can be integrated with silicon photonics and complementary metal-oxide-semiconductors (CMOS) processing by back-end-of-the-line steps. Here, we demonstrate a silicon waveguide-integrated light source and photodetector based on a p-n junction of bilayer MoTe2, a TMD semiconductor with an infrared bandgap. This state-of-the-art fabrication technology provides new opportunities for integrated optoelectronic systems.
NASA Technical Reports Server (NTRS)
Mohammed, Anil
2011-01-01
This paper focuses on integrating a large hatch penetration into inflatable modules of various constructions. This paper also compares load predictions with test measurements. The strain was measured by utilizing photogrammetric methods and strain gages mounted to select clevises that interface with the structural webbings. Bench testing showed good correlation between strain data collected from an extensometer and photogrammetric measurements, even when the material transitioned from the low load to high load strain region of the curve. The full-scale torus design module showed mixed results as well in the lower load and high strain regions. After thorough analysis of photogrammetric measurements, strain gage measurements, and predicted load, the photogrammetric measurements seem to be off by a factor of two.
Internet virtual studio: low-cost augmented reality system for WebTV
NASA Astrophysics Data System (ADS)
Sitnik, Robert; Pasko, Slawomir; Karaszewski, Maciej; Witkowski, Marcin
2008-02-01
In this paper a concept of a Internet Virtual Studio as a modern system for production of news, entertainment, educational and training material is proposed. This system is based on virtual studio technology and integrated with multimedia data base. Its was developed for web television content production. In successive subentries the general system architecture, as well as the architecture of modules one by one is discussed. The authors describe each module by presentation of a brief information about work principles and technical limitations. The presentation of modules is strictly connected with a presentation of their capabilities. Results produced by each of them are shown in the form of exemplary images. Finally, exemplary short production is presented and discussed.
Low loss poly-silicon for high performance capacitive silicon modulators.
Douix, Maurin; Baudot, Charles; Marris-Morini, Delphine; Valéry, Alexia; Fowler, Daivid; Acosta-Alba, Pablo; Kerdilès, Sébastien; Euvrard, Catherine; Blanc, Romuald; Beneyton, Rémi; Souhaité, Aurélie; Crémer, Sébastien; Vulliet, Nathalie; Vivien, Laurent; Boeuf, Frédéric
2018-03-05
Optical properties of poly-silicon material are investigated to be integrated in new silicon photonics devices, such as capacitive modulators. Test structure fabrication is done on 300 mm wafer using LPCVD deposition: 300 nm thick amorphous silicon layers are deposited on thermal oxide, followed by solid phase crystallization anneal. Rib waveguides are fabricated and optical propagation losses measured at 1.31 µm. Physical analysis (TEM ASTAR, AFM and SIMS) are used to assess the origin of losses. Optimal deposition and annealing conditions have been defined, resulting in 400 nm-wide rib waveguides with only 9.2-10 dB/cm losses.
Module degradation catalyzed by metal-encapsulation reactions
NASA Technical Reports Server (NTRS)
Gallagher, B. D.
1983-01-01
Four major properties are considered to be relevant in determining service life of a photovoltaic module: (1) Mechanical: creep resistance, modulus, tensile strength; (2) Optical: integrated transmission at 0.4 to 1.1 m wavelength; (3) Chemical: inertness with respect to metals and other components, retention of stabilizers, etc. and (4) Electrical; maintaining effective isolation of conductive components. These properties were measured after exposing polymer specimens to three types of accelerated stress: thermal, ultraviolet radiation and metal catalysts. These conditions give rise to a large number of complex interrelated free-radical reactions that result in the deterioration of polymeric materials.
Rolling dry-coupled transducers for ultrasonic inspections of aging aircraft structures
NASA Astrophysics Data System (ADS)
Komsky, Igor N.
2004-07-01
Some advanced aircraft materials or coatings are porous or otherwise sensitive to the application of water, gel, or some other ultrasonic couplants. To overcome the problems associated with the liquid coupling medium, dry-coupled rolling modules were developed at Northwestern University for the transmission of both longitudinal and transverse ultrasonic waves at frequencies up to 10 MHz. Dry-coupled ultrasonic modules contain solid core internal stators and solid or flexible external rotors with the flexible polymer substrates. Two types of the dry-coupled modules are under development. Cylindrical base transducer modules include solid core cylindrical rotors with flexible polymer substrates that rotate around the stators with ultrasonic elements. Dry-coupled modules with elongated bases contain solid core stators and flexible track-like polymer substrates that rotate around the stators as rotors of the modules. The elongated base modules have larger contact interfaces with the inspection surface in comparison with the cylindrical base modules. Some designs of the dry-coupled rolling modules contain several ultrasonic elements with different incident angles or a variable angle unit for rapid adjustments of incident angles. The prototype dry-coupled rolling modules were integrated with the portable ultrasonic inspection systems and tested on a number of Boeing aircraft structures.
RF to millimeter wave integration and module technologies
NASA Astrophysics Data System (ADS)
Vähä-Heikkilä, T.
2015-04-01
Radio Frequency (RF) consumer applications have boosted silicon integrated circuits (IC) and corresponding technologies. More and more functions are integrated to ICs and their performance is also increasing. However, RF front-end modules with filters and switches as well as antennas still need other way of integration. This paper focuses to RF front-end module and antenna developments as well as to the integration of millimeter wave radios. VTT Technical Research Centre of Finland has developed both Low Temperature Co-fired Ceramics (LTCC) and Integrated Passive Devices (IPD) integration platforms for RF and millimeter wave integrated modules. In addition to in-house technologies, VTT is using module and component technologies from other commercial sources.
Advances in Materials for Recent Low-Profile Implantable Bioelectronics
Kim, Yun-Soung; Tillman, Bryan W.; Chun, Youngjae
2018-01-01
The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material’s property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities. PMID:29596359
NASA Astrophysics Data System (ADS)
Weiss, J. R. M.; Lamprecht, T.; Meier, N.; Dangel, R.; Horst, F.; Jubin, D.; Beyeler, R.; Offrein, B. J.
2010-02-01
We report on the co-packaging of electrical CMOS transceiver and VCSEL chip arrays on a flexible electrical substrate with optical polymer waveguides. The electro-optical components are attached to the substrate edge and butt-coupled to the waveguides. Electrically conductive silver-ink connects them to the substrate at an angle of 90°. The final assembly contacts the surface of a package laminate with an integrated compressible connector. The module can be folded to save space, requires only a small footprint on the package laminate and provides short electrical high-speed signal paths. With our approach, the electro-optical package becomes a compact electro-optical module with integrated polymer waveguides terminated with either optical connectors (e.g., at the card edge) or with an identical assembly for a second processor on the board. Consequently, no costly subassemblies and connectors are needed, and a very high integration density and scalability to virtually arbitrary channel counts and towards very high data rates (20+ Gbps) become possible. Future cost targets of much less than US$1 per Gbps will be reached by employing standard PCB materials and technologies that are well established in the industry. Moreover, our technology platform has both electrical and optical connectivity and functionality.
Integrating Module - NEMS Documentation
2014-01-01
Provides an overview of the complete National Energy Modeling System (NEMS) model, and includes brief descriptions of the modules with which the Integrating Module interacts. The emphasis and focus, however, is on the structure and function of the Integrating Module of NEMS.
Bolotnikov, A. E.; Ackley, K.; Camarda, G. S.; ...
2015-07-28
We developed a robust and low-cost array of virtual Frisch-grid CdZnTe (CZT) detectors coupled to a front-end readout ASIC for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6x6x15 mm 3 detectors grouped into 3x3 sub-arrays of 2x2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readoutmore » electronics. The further enhancement of the arrays’ performance and reduction of their cost are made possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.« less
Solar Thermoelectricity via Advanced Latent Heat Storage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olsen, Michele L.; Rea, J.; Glatzmaier, Greg C.
2016-05-31
We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a 'thermalmore » valve,' which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.« less
Solar thermoelectricity via advanced latent heat storage
NASA Astrophysics Data System (ADS)
Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.
2016-05-01
We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.
Spin-Based Devices for Magneto-Optoelectronic Integrated Circuits
2009-04-29
bulk material and matches that in quantum wells. While these simple linear relationships hold for spin-polarized light-emitting diodes (spin-LEDs...temperature. The quantum efficiency and hence r| increases with decreasing temperature. The individual circuit elements, 33 therefore, exhibit the...Injection, Threshold Reduction and Output Circular Polarization Modulation in Quantum Well and Quantum Dot Semiconductor Spin Polarized Lasers working
ERIC Educational Resources Information Center
Goodson-Espy, Tracy; Cifarelli, Victor V.; Pugalee, David; Lynch-Davis, Kathleen; Morge, Shelby; Salinas, Tracie
2014-01-01
This study explored how mathematics content and methods courses for preservice elementary and middle school teachers could be improved through the integration of a set of instructional materials based on the National Assessment of Educational Progress (NAEP). A set of eight instructional modules was developed and tested. The study involved 7…
Semiconductor diode with external field modulation
Nasby, Robert D.
2000-01-01
A non-destructive-readout nonvolatile semiconductor diode switching device that may be used as a memory element is disclosed. The diode switching device is formed with a ferroelectric material disposed above a rectifying junction to control the conduction characteristics therein by means of a remanent polarization. The invention may be used for the formation of integrated circuit memories for the storage of information.
NASA Astrophysics Data System (ADS)
Gao, Yuanda
Graphene has emerged as an appealing material for a variety of optoelectronic applications due to its unique electrical and optical characteristics. In this thesis, I will present recent advances in integrating graphene and graphene-boron nitride (BN) heterostructures with confined optical architectures, e.g. planar photonic crystal (PPC) nanocavities and silicon channel waveguides, to make this otherwise weakly absorbing material optically opaque. Based on these integrations, I will further demonstrate the resulting chip-integrated optoelectronic devices for optical interconnects. After transferring a layer of graphene onto PPC nanocavities, spectral selectivity at the resonance frequency and orders-of-magnitude enhancement of optical coupling with graphene have been observed in infrared spectrum. By applying electrostatic potential to graphene, electro-optic modulation of the cavity reflection is possible with contrast in excess of 10 dB. And furthermore, a novel and complex modulator device structure based on the cavity-coupled and BN-encapsulated dual-layer graphene capacitor is demonstrated to operate at a speed of 1.2 GHz. On the other hand, an enhanced broad-spectrum light-graphene interaction coupled with silicon channel waveguides is also demonstrated with ?0.1 dB/?m transmission attenuation due to graphene absorption. A waveguide-integrated graphene photodetector is fabricated and shown 0.1 A/W photoresponsivity and 20 GHz operation speed. An improved version of a similar photodetector using graphene-BN heterostructure exhibits 0.36 A/W photoresponsivity and 42 GHz response speed. The integration of graphene and graphene-BN heterostructures with nanophotonic architectures promises a new generation of compact, energy-efficient, high-speed optoelectronic device concepts for on-chip optical communications that are not yet feasible or very difficult to realize using traditional bulk semiconductors.
Science Data Report for the Optical Properties Monitor (OPM) Experiment
NASA Technical Reports Server (NTRS)
Wilkes, Donald R.; Zwiener, James M.
1999-01-01
Long term stability of spacecraft materials when exposed to the space environment continues to be a major area of investigation. The natural and induced environment surrounding a spacecraft can decrease material performance and limit useful lifetimes. The Optical Properties Monitor (OPM) experiment provided the capability to perform the important flight testing of materials and was flown on the Russian Mir Station to study the long term effects of the natural and induced space environment on materials. The core of the OPM in-flight analysis was three independent optical instruments. These instruments included an integrating sphere spectral reflectometer, a vacuum ultraviolet spectrometer, and a Total Integrated Scatter instrument. The OPM also monitored selected components of the environment including molecular contamination. The OPM was exposed on the exterior of the Mir Docking Module for approximately 8-1/2 months. This report describes the OPM experiment, a brief background of its development, program organization, experiment description, mission overview including space environment definition, performance overview, materials data including flight and ground data, in-depth post flight analysis including ground analysis measurements and a summary discussion of the findings and results.
Yu, Woo Jong; Liu, Yuan; Zhou, Hailong; Yin, Anxiang; Li, Zheng; Huang, Yu
2014-01-01
Layered materials of graphene and MoS2, for example, have recently emerged as an exciting material system for future electronics and optoelectronics. Vertical integration of layered materials can enable the design of novel electronic and photonic devices. Here, we report highly efficient photocurrent generation from vertical heterostructures of layered materials. We show that vertically stacked graphene–MoS2–graphene and graphene–MoS2–metal junctions can be created with a broad junction area for efficient photon harvesting. The weak electrostatic screening effect of graphene allows the integration of single or dual gates under and/or above the vertical heterostructure to tune the band slope and photocurrent generation. We demonstrate that the amplitude and polarity of the photocurrent in the gated vertical heterostructures can be readily modulated by the electric field of an external gate to achieve a maximum external quantum efficiency of 55% and internal quantum efficiency up to 85%. Our study establishes a method to control photocarrier generation, separation and transport processes using an external electric field. PMID:24162001
Kim, David K; Lai, Yuming; Diroll, Benjamin T; Murray, Christopher B; Kagan, Cherie R
2012-01-01
Colloidal semiconductor nanocrystals are emerging as a new class of solution-processable materials for low-cost, flexible, thin-film electronics. Although these colloidal inks have been shown to form single, thin-film field-effect transistors with impressive characteristics, the use of multiple high-performance nanocrystal field-effect transistors in large-area integrated circuits has not been shown. This is needed to understand and demonstrate the applicability of these discrete nanocrystal field-effect transistors for advanced electronic technologies. Here we report solution-deposited nanocrystal integrated circuits, showing nanocrystal integrated circuit inverters, amplifiers and ring oscillators, constructed from high-performance, low-voltage, low-hysteresis CdSe nanocrystal field-effect transistors with electron mobilities of up to 22 cm(2) V(-1) s(-1), current modulation >10(6) and subthreshold swing of 0.28 V dec(-1). We fabricated the nanocrystal field-effect transistors and nanocrystal integrated circuits from colloidal inks on flexible plastic substrates and scaled the devices to operate at low voltages. We demonstrate that colloidal nanocrystal field-effect transistors can be used as building blocks to construct complex integrated circuits, promising a viable material for low-cost, flexible, large-area electronics.
Organic printed photonics: From microring lasers to integrated circuits
Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng
2015-01-01
A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 105, which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices. PMID:26601256
Organic printed photonics: From microring lasers to integrated circuits.
Zhang, Chuang; Zou, Chang-Ling; Zhao, Yan; Dong, Chun-Hua; Wei, Cong; Wang, Hanlin; Liu, Yunqi; Guo, Guang-Can; Yao, Jiannian; Zhao, Yong Sheng
2015-09-01
A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 10(5), which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices.
Gain modulation by graphene plasmons in aperiodic lattice lasers
NASA Astrophysics Data System (ADS)
Chakraborty, S.; Marshall, O. P.; Folland, T. G.; Kim, Y.-J.; Grigorenko, A. N.; Novoselov, K. S.
2016-01-01
Two-dimensional graphene plasmon-based technologies will enable the development of fast, compact, and inexpensive active photonic elements because, unlike plasmons in other materials, graphene plasmons can be tuned via the doping level. Such tuning is harnessed within terahertz quantum cascade lasers to reversibly alter their emission. This is achieved in two key steps: first, by exciting graphene plasmons within an aperiodic lattice laser and, second, by engineering photon lifetimes, linking graphene’s Fermi energy with the round-trip gain. Modal gain and hence laser spectra are highly sensitive to the doping of an integrated, electrically controllable, graphene layer. Demonstration of the integrated graphene plasmon laser principle lays the foundation for a new generation of active, programmable plasmonic metamaterials with major implications across photonics, material sciences, and nanotechnology.
NASA Technical Reports Server (NTRS)
Kleinstein, G. G.; Gunzburger, M. D.
1976-01-01
An integral conservation law for wave numbers is considered. In order to test the validity of the proposed conservation law, a complete solution for the reflection and transmission of an acoustic wave impinging normally on a material interface moving at a constant speed is derived. The agreement between the frequency condition thus deduced from the dynamic equations of motion and the frequency condition derived from the jump condition associated with the integral equation supports the proposed law as a true conservation law. Additional comparisons such as amplitude discontinuities and Snells' law in a moving media further confirm the stated proposition. Results are stated concerning frequency and wave number relations across a shock front as predicted by the proposed conservation law.
NASA welding assessment program
NASA Technical Reports Server (NTRS)
Stofel, E. J.
1984-01-01
A long duration test has been conducted for comparing various methods of attaching electrical interconnects to solar cells for near Earth orbit spacecraft. Representative solar array modules have been thermally cycled for 36,000 cycles between -80 and +80 C on this JPL and NASA Lewis Research Center sponsored work. This test simulates the environmental stress of more than 6 years on a near Earth spacecraft as it cycles in and out of the Earth's shadow. Evaluations of the integrity of these modules were made by visual and by electrical examinations before starting the cycling and then at periodic intervals during the cycling tests. Modules included examples of parallel gap and of ultrasonic welding, as well as soldering. The materials and fabrication processes are state of the art, suitable for forming large solar arrays of spacecraft quality. The modules survived his extensive cycling without detectable degradation in their ability to generate power under sunlight illumination.
Development and Sizing of the JWST Integrated Science Instrument Module (ISIM) Metering Structure
NASA Technical Reports Server (NTRS)
Johnston, John; Kunt, Cengiz; Bartoszyk, Andrew; Hendricks, Steve; Cofie, Emmanuel
2006-01-01
The JWST Integrated Science Instrument Module (ISIM) includes a large metering structure (approx. 2m x 2m x 1.5m) that houses the science instruments and guider. Stringent dimensional stability and repeatability requirements combined with mass limitations led to the selection of a composite bonded frame design comprised of biased laminate tubes. Even with the superb material specific stiffness, achieving the required frequency for the given mass allocations in conjunction with severe spatial limitations imposed by the instrument complement has proven challenging. In response to the challenge, the ISIM structure team considered literally over 100 primary structure topology and kinematic mount configurations, and settled on a concept comprised of over 70 m of tubes, over 50 bonded joint assemblies, and a "split bi-pod" kinematic mount configuration. In this paper, we review the evolution of the ISIM primary structure topology and kinematic mount configuration to the current baseline concept.
NREL/industry interaction: Amorphous silicon alloy research team formation
NASA Astrophysics Data System (ADS)
Luft, Werner
1994-06-01
The low material cost and proven manufacturability of amorphous silicon (a-Si) alloy photovoltaic technology make it ideally suited for large-scale terrestrial applications. The present efficiency of a-Si alloy modules is, however, much lower than the 15% stable efficiency that would lead to significant penetration of the electric utility bulk-power market. The slow progress in achieving high stabilized a-Si alloy module efficiencies may in part be attributed to the fact that only in the last few years did we emphasize stable efficiencies. A mission-focused integrated effort among the a-Si PV industry, universities, and the National Renewable Energy Laboratory (NREL) would help. To foster research integration, NREL has established four research teams with significant industry participation. In the 11 months since the research team formation, a close interaction among the a-Si PV industry, universities, and NREL has been achieved and has resulted in mission-directed research.
NREL/industry interaction: Amorphous silicon alloy research team formation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Luft, W.
1994-06-30
The low material cost and proven manufacturability of amorphous silicon (a-Si) alloy photovoltaic technology make it ideally suited for large-scale terrestrial applications. The present efficiency of a-Si alloy modules is, however, much lower than the 15% stable efficiency that would lead to [ital significant] penetration of the electric utility bulk-power market. The slow progress in achieving high stabilized a-Si alloy module efficiencies may in part be attributed to the fact that only in the last few years did we emphasize stable efficiencies. A mission-focused integrated effort among the a-Si PV industry, universities, and the National Renewable Energy Laboratory (NREL) wouldmore » help. To foster research integration, NREL has established four research teams with significant industry participation. In the 11 months since the research team formation, a close interaction among the a-Si PV industry, universities, and NREL has been achieved and has resulted in mission-directed research.« less
Lee, Ming-Che; Chuang, Kei-Shih; Hsu, Tien-Cheng; Lee, Chien-Ding
2016-11-01
Collection of radiation dose derived from radiological examination is necessary not only for radiation protection, but also for fulfillment of structured reports. However, the material regarding of radiation dose cannot be directly utilized by the Radiological Information System (RIS) since it is generated and only stored in the Picture Archiving and Communication System (PACS). In this paper, an integration reporting module is proposed to facilitate handling of dose information and structured reporting by providing two functionalities. First, a gateway is established to automatically collect the related information from PACS for further analyzing and monitoring the accumulated radiation. Second, the designated structured reporting patterns with corresponding radiation dose measurements can be acquired by radiologists as necessary. In the design, the radiation dose collection gateway and the well-established pattern are collocated to achieve that there is no need to do manual entry for structured reporting, thus increasing productivity and medical quality.
NASA Astrophysics Data System (ADS)
Pedelì, C.
2013-07-01
In order to make the most of the digital outsourced documents, based on new technologies (e.g.: 3D LASER scanners, photogrammetry, etc.), a new approach was followed and a new ad hoc information system was implemented. The obtained product allow to the final user to reuse and manage the digital documents providing graphic tools and an integrated specific database to manage the entire documentation and conservation process, starting from the condition assessment until the conservation / restoration work. The system is organised on two main modules: Archaeology and Conservation. This paper focus on the features and the advantages of the second one. In particular it is emphasized its logical organisation, the possibility to easily mapping by using a very precise 3D metric platform, to benefit of the integrated relational database which allows to well organise, compare, keep and manage different kind of information at different level. Conservation module can manage along the time the conservation process of a site, monuments, object or excavation and conservation work in progress. An alternative approach called OVO by the author of this paper, force the surveyor to observe and describe the entity decomposing it on functional components, materials and construction techniques. Some integrated tools as the "ICOMOS-ISCS Illustrated glossary … " help the user to describe pathologies with a unified approach and terminology. Also the conservation project phase is strongly supported to envision future intervention and cost. A final section is devoted to record the conservation/restoration work already done or in progress. All information areas of the conservation module are interconnected to each other to allows to the system a complete interchange of graphic and alphanumeric data. The conservation module it self is connected to the archaeological one to create an interdisciplinary daily tool.
Zhou, Wenbin; Fan, Qingxia; Zhang, Qiang; Cai, Le; Li, Kewei; Gu, Xiaogang; Yang, Feng; Zhang, Nan; Wang, Yanchun; Liu, Huaping; Zhou, Weiya; Xie, Sishen
2017-01-01
It is a great challenge to substantially improve the practical performance of flexible thermoelectric modules due to the absence of air-stable n-type thermoelectric materials with high-power factor. Here an excellent flexible n-type thermoelectric film is developed, which can be conveniently and rapidly prepared based on the as-grown carbon nanotube continuous networks with high conductivity. The optimum n-type film exhibits ultrahigh power factor of ∼1,500 μW m−1 K−2 and outstanding stability in air without encapsulation. Inspired by the findings, we design and successfully fabricate the compact-configuration flexible TE modules, which own great advantages compared with the conventional π-type configuration modules and well integrate the superior thermoelectric properties of p-type and n-type carbon nanotube films resulting in a markedly high performance. Moreover, the research results are highly scalable and also open opportunities for the large-scale production of flexible thermoelectric modules. PMID:28337987
CPV for the rooftop market: novel approaches to tracking integration in photovoltaic modules
NASA Astrophysics Data System (ADS)
Apostoleris, Harry; Stefancich, Marco; Alexander-Katz, Alfredo; Chiesa, Matteo
2016-03-01
Concentrated photovoltaics (CPV) has long been recognized as an effective approach to enabling the use of high cost, high-efficiency solar cells for enhanced solar energy conversion, but is excluded from the domestic rooftop market due to the requirement that solar concentrators track the sun. This market may be opened up by integrating of the tracking mechanism into the module itself. Tracking integration may take the form of a miniaturization of a conventional tracking apparatus, or optical tracking, in which tracking is achieved through variation of optical properties such as refractive index or transparency rather than mechanical movement of the receiver. We have demonstrated a simple system using a heat-responsive transparency switching material to create a moving aperture that tracks the position of a moving light spot. We use this behavior to create a concentrating light trap with a moving aperture that reactively tracks the sun. Taking the other approach, we have fabricated 3D-printed parabolic mini-concentrators which can track the sun using small motors in a low-profile geometry. We characterize the performance of the concentrators and consider the impact of tracking integration on the broader PV market.
Assessing Student Learning about the Earth through the InTeGrate Project
NASA Astrophysics Data System (ADS)
Gilbert, L. A.; Iverson, E. A. R.; Steer, D. N.; Birnbaum, S. J.; Manduca, C. A.
2016-12-01
InTeGrate, a five-year community-based project comprised of faculty in the sciences and other disciplines, educational specialists, and evaluation experts at diverse institutions, instills learning about Earth in the context of societal issues through teaching materials developed into 2-3 week modules or courses. Materials were tested by over 135 materials authors and faculty interested in using these materials in undergraduate courses at a range of institution types across the US in geoscience, engineering, humanities, and social science courses. To assess impact on student learning, the InTeGrate project has collected student work from over 4,600 students enrolled in courses using these materials. To evaluate the influence of the materials on learning gains related to geoscience literacy, a set of 8 multiple choice items were developed, tested, and then administered in the first and last week of class in approximately 180 courses. The items were developed by 14 community members with assessment expertise and address content and concepts in the Earth, Climate, Atmosphere, and Ocean Science literacy documents. In a sample of 2,023 paired first and last week responses, students exhibit a 10% normalized gain (equivalent to 1 point of a 12 point total) regardless of their initial score. Students in the lowest quartile at the beginning of the course demonstrate the highest gains (4th quartile gain of 1.8) versus the higher quartile where a ceiling effect is present. In addition, a free-response essay was administered in the last week of the course which tests students' understanding for how Earth system interactions influence people's ability to make decisions about global societal challenges. Analysis of these essays demonstrates a strong relationship between the InTeGrate content and the subject matter of the student essay. These preliminary findings suggest that the use of InTeGrate materials increases students' understanding of geoscience literacies and the materials give students a topical hook for connecting learning about Earth to societal challenges.
Perspective: The future of quantum dot photonic integrated circuits
NASA Astrophysics Data System (ADS)
Norman, Justin C.; Jung, Daehwan; Wan, Yating; Bowers, John E.
2018-03-01
Direct epitaxial integration of III-V materials on Si offers substantial manufacturing cost and scalability advantages over heterogeneous integration. The challenge is that epitaxial growth introduces high densities of crystalline defects that limit device performance and lifetime. Quantum dot lasers, amplifiers, modulators, and photodetectors epitaxially grown on Si are showing promise for achieving low-cost, scalable integration with silicon photonics. The unique electrical confinement properties of quantum dots provide reduced sensitivity to the crystalline defects that result from III-V/Si growth, while their unique gain dynamics show promise for improved performance and new functionalities relative to their quantum well counterparts in many devices. Clear advantages for using quantum dot active layers for lasers and amplifiers on and off Si have already been demonstrated, and results for quantum dot based photodetectors and modulators look promising. Laser performance on Si is improving rapidly with continuous-wave threshold currents below 1 mA, injection efficiencies of 87%, and output powers of 175 mW at 20 °C. 1500-h reliability tests at 35 °C showed an extrapolated mean-time-to-failure of more than ten million hours. This represents a significant stride toward efficient, scalable, and reliable III-V lasers on on-axis Si substrates for photonic integrate circuits that are fully compatible with complementary metal-oxide-semiconductor (CMOS) foundries.
NASA Technical Reports Server (NTRS)
Springer, Darlene
1989-01-01
Different aspects of Space Station Environmental Control and Life Support System (ECLSS) testing are currently taking place at Marshall Space Flight Center (MSFC). Unique to this testing is the variety of test areas and the fact that all are located in one building. The north high bay of building 4755, the Core Module Integration Facility (CMIF), contains the following test areas: the Subsystem Test Area, the Comparative Test Area, the Process Material Management System (PMMS), the Core Module Simulator (CMS), the End-use Equipment Facility (EEF), and the Pre-development Operational System Test (POST) Area. This paper addresses the facility that supports these test areas and briefly describes the testing in each area. Future plans for the building and Space Station module configurations will also be discussed.
Innovative Ballasted Flat Roof Solar PV Racking System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peek, Richard T.
2014-12-15
The objective of this project was to reduce the cost of racking for PV solar on flat commercial rooftops. Cost reductions would come from both labor savings and material savings related to the installation process. The rack would need to accommodate the majority of modules available on the market. Cascade Engineering has a long history of converting traditional metal type applications over to plastic. Injection molding of plastics have numerous advantages including selection of resin for the application, placing the material exactly where it is needed, designing in features that will speed up the installation process, and weight reduction ofmore » the array. A plastic rack would need to meet the requirements of UL2703, Mounting systems, mounting devices, clamping/retention devices, and ground lugs for use with flat-plate photovoltaic modules and panels. Comparing original data to the end of project racking design, racking material costs were reduced 50% and labor costs reduced 64%. The racking product accommodates all 60 and 72 cell panels on the market, meets UL2703 requirements, contributes only 1.3 pounds per square foot of weight to the array, requires little ballast to secure the array, automatically grounds the module when the module is secured, stacks/nests well for shipping/fewer lifts to the roof, provides integrated wire routing, allows water to drain on the roof, and accommodates various seismic roof connections. Project goals were achieved as noted in the original funding application.« less
Advances in polycrystalline thin-film photovoltaics for space applications
NASA Technical Reports Server (NTRS)
Lanning, Bruce R.; Armstrong, Joseph H.; Misra, Mohan S.
1994-01-01
Polycrystalline, thin-film photovoltaics represent one of the few (if not the only) renewable power sources which has the potential to satisfy the demanding technical requirements for future space applications. The demand in space is for deployable, flexible arrays with high power-to-weight ratios and long-term stability (15-20 years). In addition, there is also the demand that these arrays be produced by scalable, low-cost, high yield, processes. An approach to significantly reduce costs and increase reliability is to interconnect individual cells series via monolithic integration. Both CIS and CdTe semiconductor films are optimum absorber materials for thin-film n-p heterojunction solar cells, having band gaps between 0.9-1.5 ev and demonstrated small area efficiencies, with cadmium sulfide window layers, above 16.5 percent. Both CIS and CdTe polycrystalline thin-film cells have been produced on a laboratory scale by a variety of physical and chemical deposition methods, including evaporation, sputtering, and electrodeposition. Translating laboratory processes which yield these high efficiency, small area cells into the design of a manufacturing process capable of producing 1-sq ft modules, however, requires a quantitative understanding of each individual step in the process and its (each step) effect on overall module performance. With a proper quantification and understanding of material transport and reactivity for each individual step, manufacturing process can be designed that is not 'reactor-specific' and can be controlled intelligently with the design parameters of the process. The objective of this paper is to present an overview of the current efforts at MMC to develop large-scale manufacturing processes for both CIS and CdTe thin-film polycrystalline modules. CIS cells/modules are fabricated in a 'substrate configuration' by physical vapor deposition techniques and CdTe cells/modules are fabricated in a 'superstrate configuration' by wet chemical methods. Both laser and mechanical scribing operations are used to monolithically integrate (series interconnect) the individual cells into modules. Results will be presented at the cell and module development levels with a brief description of the test methods used to qualify these devices for space applications. The approach and development efforts are directed towards large-scale manufacturability of established thin-film, polycrystalline processing methods for large area modules with less emphasis on maximizing small area efficiencies.
A Cutting-Edge Education: Incorporating Nano into the Undergraduate Curricula.
NASA Astrophysics Data System (ADS)
Zenner, Greta M.
2008-03-01
The Interdisciplinary Education Group (IEG) of the Materials Research Science and Engineering Center (MRSEC) on Nanostructured Interfaces at the University of Wisconsin-Madison (UW) develops and uses hands-on, interactive education and outreach materials to engage a variety of audiences in learning about nanotechnology and advanced materials. Many of the education products created are inspired by UW MRSEC research; and faculty, staff, and students regularly contribute to the IEG's work to share nanotechnology with a broader audience. The UW MRSEC has developed numerous teaching modules, labs, and education resources devoted to nanotechnology concepts, and many of these materials have been integrated into key introductory and advanced undergraduate courses at UW and other institutions, including small liberal arts colleges and community colleges. This effort has taken place through both the creation of new courses and the modification of existing courses to include cutting-edge content based on current research and emerging applications in nanotechnology. In this talk, I will present some of the new instructional materials we have developed based on advances in nanoscale science and technology, the implementation and integration of these materials into undergraduate curricula, and an overview of the UW MRSEC education efforts.
Post-merger evolution of a neutron star-black hole binary with neutrino transport
NASA Astrophysics Data System (ADS)
Foucart, Francois; O'Connor, Evan; Roberts, Luke; Duez, Matthew; Kidder, Lawrence; Ott, Christian; Pfeiffer, Harald; Scheel, Mark; Szilagyi, Bela; SXS Collaboration
2015-04-01
We present a first simulation of the post-merger evolution of a black hole-neutron star binary in full general relativity using an energy-integrated truncated moment formalism for neutrino transport. The moment formalism is included as a new module in the SpEC code. We describe the implementation and tests of this new module, and its use to study the formation phase of an accretion disk after a black hole-neutron star merger. We discuss differences with simpler treatments of the neutrinos, the importance of relativistic effects, and the impact of the formation phase of the disk on its expected long-term evolution. We also show that a small amount of material is ejected in the polar region during the circularization of the disk and its interactions with fallback material, and discuss its effects on potential electromagnetic counterparts to the merger.
Integrated microsystems packaging approach with LCP
NASA Astrophysics Data System (ADS)
Jaynes, Paul; Shacklette, Lawrence W.
2006-05-01
Within the government communication market there is an increasing push to further miniaturize systems with the use of chip-scale packages, flip-chip bonding, and other advances over traditional packaging techniques. Harris' approach to miniaturization includes these traditional packaging advances, but goes beyond this level of miniaturization by combining the functional and structural elements of a system, thus creating a Multi-Functional Structural Circuit (MFSC). An emerging high-frequency, near hermetic, thermoplastic electronic substrate material, Liquid Crystal Polymer (LCP), is the material that will enable the combination of the electronic circuit and the physical structure of the system. The first embodiment of this vision for Harris is the development of a battlefield acoustic sensor module. This paper will introduce LCP and its advantages for MFSC, present an example of the work that Harris has performed, and speak to LCP MFSCs' potential benefits to miniature communications modules and sensor platforms.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Zhihua; Evans, Philip G.; Haglund, Richard F.
Mastering dynamic free-space spectral control and modulation in the near-infrared (NIR) and optical regimes remains a challenging task that is hindered by the available functional materials at high frequencies. In this work, we have realized an efficient metadevice capable of spectral control by minimizing the thermal mass of a vanadium dioxide phase-change material (PCM) and placing the PCM at the feed gap of a bow-tie field antenna. The device has an experimentally measured tuning range of up to 360 nm in the NIR and a modulation depth of 33% at the resonant wavelength. The metadevice is configured for integrated andmore » local heating, leading to faster switching and more precise spatial control compared with devices based on phase-change thin films. We envisage that the combined advantages of this device will open new opportunities for signal processing, memory, security, and holography at optical frequencies.« less
Intelligent Luminescence for Communication Display and Identification
2007-07-18
34Fabrication of two-dimensional photonic crystals using interference lithography and electrodeposition of CdSe," Appl. Phys. Letts. 79, 3392-3394 (2001). 7...studies were performed on holographically derived structures fonned in SUS by a four-laser beam interference pattern. As shown in Figure 7 a SUS polymer...dielectric material, as patterned by electron-beam lithography , consisting of a periodic dielectric modulation with integrated line, point and
Manifold, bus support and coupling arrangement for solid oxide fuel cells
Parry, Gareth W.
1989-01-01
Individual, tubular solid oxide fuel cells (SOFCs) are assembled into bundles called a module within a housing, with a plurality of modules arranged end-to-end in a linear, stacked configuration called a string. A common set of piping comprised of a suitable high temperture resistant material (1) provides fuel and air to each module housing, (2) serves as electrically conducting buses, and (3) provides structural support for a string of SOFC modules. The piping thus forms a manfold for directing fuel and air to each module in a string and makes electrical contact with the module's anode and cathode to conduct the DC power generated by the SOFC. The piping also provides structureal support for each individual module and maintains each string of modules as a structurally integral unit for ensuring high strength in a large 3-dimensional array of SOFC modules. Ceramic collars are used to connect fuel and air inlet piping to each of the electrodes in an SOFC module and provide (1) electrical insulation for the current carrying bus bars and gas manifolds, (2) damping for the fuel and air inlet piping, and (3) proper spacing between the fuel and air inlet piping to prevent contact between these tubes and possible damage to the SOFC.
Hydrogen storage and integrated fuel cell assembly
Gross, Karl J.
2010-08-24
Hydrogen is stored in materials that absorb and desorb hydrogen with temperature dependent rates. A housing is provided that allows for the storage of one or more types of hydrogen-storage materials in close thermal proximity to a fuel cell stack. This arrangement, which includes alternating fuel cell stack and hydrogen-storage units, allows for close thermal matching of the hydrogen storage material and the fuel cell stack. Also, the present invention allows for tailoring of the hydrogen delivery by mixing different materials in one unit. Thermal insulation alternatively allows for a highly efficient unit. Individual power modules including one fuel cell stack surrounded by a pair of hydrogen-storage units allows for distribution of power throughout a vehicle or other electric power consuming devices.
Three-Dimensional Finite-Element Simulation for a Thermoelectric Generator Module
NASA Astrophysics Data System (ADS)
Hu, Xiaokai; Takazawa, Hiroyuki; Nagase, Kazuo; Ohta, Michihiro; Yamamoto, Atsushi
2015-10-01
A three-dimensional closed-circuit numerical model of a thermoelectric generator (TEG) module has been constructed with COMSOL® Multiphysics to verify a module test system. The Seebeck, Peltier, and Thomson effects and Joule heating are included in the thermoelectric conversion model. The TEG model is employed to simulate the operation of a 16-leg TEG module based on bismuth telluride with temperature-dependent material properties. The module is mounted on a test platform, and simulated by combining the heat conduction process and thermoelectric conversion process. Simulation results are obtained for the terminal voltage, output power, heat flow, and efficiency as functions of the electric current; the results are compared with measurement data. The Joule and Thomson heats in all the thermoelectric legs, as functions of the electric current, are calculated by finite-element volume integration over the entire legs. The Peltier heat being pumped at the hot side and released at the cold side of the module are also presented in relation to the electric current. The energy balance relations between heat and electricity are verified to support the simulation.
An analysis of international nuclear fuel supply options
NASA Astrophysics Data System (ADS)
Taylor, J'tia Patrice
As the global demand for energy grows, many nations are considering developing or increasing nuclear capacity as a viable, long-term power source. To assess the possible expansion of nuclear power and the intricate relationships---which cover the range of economics, security, and material supply and demand---between established and aspirant nuclear generating entities requires models and system analysis tools that integrate all aspects of the nuclear enterprise. Computational tools and methods now exist across diverse research areas, such as operations research and nuclear engineering, to develop such a tool. This dissertation aims to develop methodologies and employ and expand on existing sources to develop a multipurpose tool to analyze international nuclear fuel supply options. The dissertation is comprised of two distinct components: the development of the Material, Economics, and Proliferation Assessment Tool (MEPAT), and analysis of fuel cycle scenarios using the tool. Development of MEPAT is aimed for unrestricted distribution and therefore uses publicly available and open-source codes in its development when possible. MEPAT is built using the Powersim Studio platform that is widely used in systems analysis. MEPAT development is divided into three modules focusing on: material movement; nonproliferation; and economics. The material movement module tracks material quantity in each process of the fuel cycle and in each nuclear program with respect to ownership, location and composition. The material movement module builds on techniques employed by fuel cycle models such as the Verifiable Fuel Cycle Simulation (VISION) code developed at the Idaho National Laboratory under the Advanced Fuel Cycle Initiative (AFCI) for the analysis of domestic fuel cycle. Material movement parameters such as lending and reactor preference, as well as fuel cycle parameters such as process times and material factors are user-specified through a Microsoft Excel(c) data spreadsheet. The material movement module is the largest of the three, and the two other modules that assess nonproliferation and economics of the options are dependent on its output. Proliferation resistance measures from literature are modified and incorporated in MEPAT. The module to assess the nonproliferation of the supply options allows the user to specify defining attributes for the fuel cycle processes, and determines significant quantities of materials as well as measures of proliferation resistance. The measure is dependent on user-input and material information. The economics module allows the user to specify costs associated with different processes and other aspects of the fuel cycle. The simulation tool then calculates economic measures that relate the cost of the fuel cycle to electricity production. The second part of this dissertation consists of an examination of four scenarios of fuel supply option using MEPAT. The first is a simple scenario illustrating the modules and basic functions of MEPAT. The second scenario recreates a fuel supply study reported earlier in literature, and compares MEPAT results with those reported earlier for validation. The third, and a rather realistic, scenario includes four nuclear programs with one program entering the nuclear energy market. The fourth scenario assesses the reactor options available to the Hashemite Kingdom of Jordan, which is currently assessing available options to introduce nuclear power in the country. The methodology developed and implemented in MEPAT to analyze the material, proliferation and economics of nuclear fuel supply options is expected to help simplify and assess different reactor and fuel options available to utilities, government agencies and international organizations.
Teaching the Anatomy of Oncology: Evaluating the Impact of a Dedicated Oncoanatomy Course
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chino, Junzo P., E-mail: junzo.chino@duke.ed; Lee, W. Robert; Madden, Richard
Purpose: Anatomic considerations are often critical in multidisciplinary cancer care. We developed an anatomy-focused educational program for radiation oncology residents integrating cadaver dissection into the didactic review of diagnostic, surgical, radiologic, and treatment planning, and herein assess its efficacy. Methods and Materials: Monthly, anatomic-site based educational modules were designed and implemented during the 2008-2009 academic year at Duke University Medical Center. Ten radiation oncology residents participated in these modules consisting of a 1-hour didactic introduction followed by a 1-hour session in the gross anatomy lab with cadavers prepared by trained anatomists. Pretests and posttests were given for six modules, andmore » post-module feedback surveys were distributed. Additional review questions testing knowledge from prior sessions were integrated into the later testing to evaluate knowledge retention. Paired analyses of pretests and postests were performed by Wilcoxon signed-rank test. Results: Ninety tests were collected and scored with 35 evaluable pretest and posttest pairs for six site-specific sessions. Posttests had significantly higher scores (median percentage correct 66% vs. 85%, p < 0.001). Of 47 evaluable paired pretest and review questions given 1-3 months after the intervention, correct responses rates were significantly higher for the later (59% vs. 86%, p = 0.008). Resident course satisfaction was high, with a median rating of 9 of 10 (IQR 8-9); with 1 being 'less effective than most educational interventions' and 10 being 'more effective than most educational interventions.' Conclusions: An integrated oncoanatomy course is associated with improved scores on post-intervention tests, sustained knowledge retention, and high resident satisfaction.« less
V-band integrated quadriphase modulator
NASA Technical Reports Server (NTRS)
Grote, A.; Chang, K.
1983-01-01
A V-band integrated circuit quadriphase shift keyed modulator/exciter for space communications systems was developed. Intersatellite communications systems require direct modulation at 60 GHz to enhance signal processing capability. For most systems, particularly space applications, small and lightweight components are essential to alleviate severe system design constraints. Thus to achieve wideband, high data rate systems, direct modulation techniques at millimeter waves using solid state integrated circuit technology are an integral part of the overall technology developments.
NASA Astrophysics Data System (ADS)
Gao, Xin; Chen, Min; Snyder, G. Jeffrey; Andreasen, Søren Juhl; Kær, Søren Knudsen
2013-07-01
To better manage the magnitude and direction of the heat flux in an exchanger-based methanol evaporator of a fuel cell system, thermoelectric (TE) modules can be deployed as TE heat flux regulators (TERs). The performance of the TE-integrated evaporator is strongly influenced by its heat exchange structure. The structure transfers the fuel cell exhaust heat to the evaporation chamber to evaporate the methanol, where TE modules are installed in between to facilitate the heat regulation. In this work, firstly, a numerical study is conducted to determine the working currents and working modes of the TERs under the system working condition fluctuations and during the system cold start. A three-dimensional evaporator model is generated in ANSYS FLUENT® by combining a compact TE model with various heat exchange structure geometries. The compact TE model can dramatically improve the computational efficiency, and uses a different material property acquisition method based on module manufacturers' datasheets. Secondly, a simulation study is carried out on the novel evaporator to minimize its thermal resistance and to assess the evaporator pressure drop. The factors studied include the type of fins in the heat exchange structure, the thickness of the fins, the axial conduction penalty, etc. Results show that the TE-integrated evaporator can work more efficiently and smoothly during both load fluctuations and system cold start, offering superior performance.
Applied optics. Gain modulation by graphene plasmons in aperiodic lattice lasers.
Chakraborty, S; Marshall, O P; Folland, T G; Kim, Y-J; Grigorenko, A N; Novoselov, K S
2016-01-15
Two-dimensional graphene plasmon-based technologies will enable the development of fast, compact, and inexpensive active photonic elements because, unlike plasmons in other materials, graphene plasmons can be tuned via the doping level. Such tuning is harnessed within terahertz quantum cascade lasers to reversibly alter their emission. This is achieved in two key steps: first, by exciting graphene plasmons within an aperiodic lattice laser and, second, by engineering photon lifetimes, linking graphene's Fermi energy with the round-trip gain. Modal gain and hence laser spectra are highly sensitive to the doping of an integrated, electrically controllable, graphene layer. Demonstration of the integrated graphene plasmon laser principle lays the foundation for a new generation of active, programmable plasmonic metamaterials with major implications across photonics, material sciences, and nanotechnology. Copyright © 2016, American Association for the Advancement of Science.
Examination of an optical transmittance test for photovoltaic encapsulation materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, David C.; Bengoechea, Jaione; Bokria, Jayesh G.
2013-09-24
The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and moremore » appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).« less
Examination of an Optical Transmittance Test for Photovoltaic Encapsulation Materials (Presentation)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, D.; Bengoechea, J.; Bokria, J.
2013-09-01
The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and moremore » appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).« less
Light Microscopy Module Imaging Tested and Demonstrated
NASA Technical Reports Server (NTRS)
Gati, Frank
2004-01-01
The Fluids Integrated Rack (FIR), a facility-class payload, and the Light Microscopy Module (LMM), a subrack payload, are integrated research facilities that will fly in the U.S. Laboratory module, Destiny, aboard the International Space Station. Both facilities are being engineered, designed, and developed at the NASA Glenn Research Center by Northrop Grumman Information Technology. The FIR is a modular, multiuser scientific research facility that is one of two racks that make up the Fluids and Combustion Facility (the other being the Combustion Integrated Rack). The FIR has a large volume dedicated for experimental hardware; easily reconfigurable diagnostics, power, and data systems that allow for unique experiment configurations; and customizable software. The FIR will also provide imagers, light sources, power management and control, command and data handling for facility and experiment hardware, and data processing and storage. The first payload in the FIR will be the LMM. The LMM integrated with the FIR is a remotely controllable, automated, on-orbit microscope subrack facility, with key diagnostic capabilities for meeting science requirements--including video microscopy to observe microscopic phenonema and dynamic interactions, interferometry to make thin-film measurements with nanometer resolution, laser tweezers to manipulate micrometer-sized particles, confocal microscopy to provide enhanced three-dimensional visualization of structures, and spectrophotometry to measure the photonic properties of materials. Vibration disturbances were identified early in the LMM development phase as a high risk for contaminating the science microgravity environment. An integrated FIR-LMM test was conducted in Glenn's Acoustics Test Laboratory to assess mechanical sources of vibration and their impact to microscopic imaging. The primary purpose of the test was to characterize the LMM response at the sample location, the x-y stage within the microscope, to vibration emissions from the FIR and LMM support structures.
Kakui, Yasutaka; Sunaga, Tomonari; Arai, Kunio; Dodgson, James; Ji, Liang; Csikász-Nagy, Attila; Carazo-Salas, Rafael; Sato, Masamitsu
2015-01-01
Integration of an external gene into a fission yeast chromosome is useful to investigate the effect of the gene product. An easy way to knock-in a gene construct is use of an integration plasmid, which can be targeted and inserted to a chromosome through homologous recombination. Despite the advantage of integration, construction of integration plasmids is energy- and time-consuming, because there is no systematic library of integration plasmids with various promoters, fluorescent protein tags, terminators and selection markers; therefore, researchers are often forced to make appropriate ones through multiple rounds of cloning procedures. Here, we establish materials and methods to easily construct integration plasmids. We introduce a convenient cloning system based on Golden Gate DNA shuffling, which enables the connection of multiple DNA fragments at once: any kind of promoters and terminators, the gene of interest, in combination with any fluorescent protein tag genes and any selection markers. Each of those DNA fragments, called a ‘module’, can be tandemly ligated in the order we desire in a single reaction, which yields a circular plasmid in a one-step manner. The resulting plasmids can be integrated through standard methods for transformation. Thus, these materials and methods help easy construction of knock-in strains, and this will further increase the value of fission yeast as a model organism. PMID:26108218
2012-01-01
Background Beyond the adoption of the principles of horizontal and vertical integration, significant planning and implementation of curriculum reform is needed. This study aimed to assess the effect of the interdisciplinary integrated Cardiovascular System (CVS) module on both student satisfaction and performance and comparing them to those of the temporally coordinated CVS module that was implemented in the previous year at the faculty of Medicine of the King Abdulaziz University, Saudi Arabia. Methods This interventional study used mixed method research design to assess student and faculty satisfaction with the level of integration within the CVS module. A team from the medical education department was assembled in 2010/2011 to design a plan to improve the CVS module integration level. After delivering the developed module, both student and faculty satisfaction as well as students performance were assessed and compared to those of the previous year to provide an idea about module effectiveness. Results Many challenges faced the medical education team during design and implementation of the developed CVS module e.g. resistance of faculty members to change, increasing the percentage of students directed learning hours from the total contact hour allotted to the module and shifting to integrated item writing in students assessment, spite of that the module achieved a significant increase in both teaching faculty and student satisfaction as well as in the module scores. Conclusion The fully integrated CVS has yielded encouraging results that individual teachers or other medical schools who attempt to reformulate their curriculum may find valuable. PMID:22747781
NASGRO 3.0: A Software for Analyzing Aging Aircraft
NASA Technical Reports Server (NTRS)
Mettu, S. R.; Shivakumar, V.; Beek, J. M.; Yeh, F.; Williams, L. C.; Forman, R. G.; McMahon, J. J.; Newman, J. C., Jr.
1999-01-01
Structural integrity analysis of aging aircraft is a critical necessity in view of the increasing numbers of such aircraft in general aviation, the airlines and the military. Efforts are in progress by NASA, the FAA and the DoD to focus attention on aging aircraft safety. The present paper describes the NASGRO software which is well-suited for effectively analyzing the behavior of defects that may be found in aging aircraft. The newly revised Version 3.0 has many features specifically implemented to suit the needs of the aircraft community. The fatigue crack growth computer program NASA/FLAGRO 2.0 was originally developed to analyze space hardware such as the Space Shuttle, the International Space Station and the associated payloads. Due to popular demand, the software was enhanced to suit the needs of the aircraft industry. Major improvements in Version 3.0 are the incorporation of the ability to read aircraft spectra of unlimited size, generation of common aircraft fatigue load blocks, and the incorporation of crack-growth models which include load-interaction effects such as retardation due to overloads and acceleration due to underloads. Five new crack-growth models, viz., generalized Willenborg, modified generalized Willenborg, constant closure model, Walker-Chang model and the deKoning-Newman strip-yield model, have been implemented. To facilitate easier input of geometry, material properties and load spectra, a Windows-style graphical user interface has been developed. Features to quickly change the input and rerun the problem as well as examine the output are incorporated. NASGRO has been organized into three modules, the crack-growth module being the primary one. The other two modules are the boundary element module and the material properties module. The boundary-element module provides the ability to model and analyze complex two-dimensional problems to obtain stresses and stress-intensity factors. The material properties module allows users to store and curve-fit fatigue-crack growth data. On-line help and documentation are provided for each of the modules. In addition to the popular PC windows version, a unix-based X-windows version of NASGRO is also available. A portable C++ class library called WxWindows was used to facilitate cross-platform availability of the software.
Science Data Report for the Optical Properties Monitor (OPM) Experiment
NASA Technical Reports Server (NTRS)
Wilkes, D. R.; Zwiener, J. M.; Carruth, Ralph (Technical Monitor)
2001-01-01
This science data report describes the Optical Properties Monitor (OPM) experiment and the data gathered during its 9-mo exposure on the Mir space station. Three independent optical instruments made up OPM: an integrating sphere spectral reflectometer, vacuum ultraviolet spectrometer, and a total integrated scatter instrument. Selected materials were exposed to the low-Earth orbit, and their performance monitored in situ by the OPM instruments. Coinvestigators from four NASA Centers, five International Space Station contractors, one university, two Department of Defense organizations, and the Russian space company, Energia, contributed samples to this experiment. These materials included a number of thermal control coatings, optical materials, polymeric films, nanocomposites, and other state-of-the-art materials. Degradation of some materials, including aluminum conversion coatings and Beta cloth, was greater than expected. The OPM experiment was launched aboard the Space Shuttle on mission STS-81 in January 1997 and transferred to the Mir space station. An extravehicular activity (EVA) was performed in April 1997 to attach the OPM experiment to the outside of the Mir/Shuttle Docking Module for space environment exposure. OPM was retrieved during an EVA in January 1998 and was returned to Earth on board the Space Shuttle on mission STS-89.
NASA Astrophysics Data System (ADS)
Hadjloum, Massinissa; El Gibari, Mohammed; Li, Hongwu; Daryoush, Afshin S.
2017-06-01
A large performance improvement of polymer phase modulators is reported by using buried in-plane coupled microstrip (CMS) driving electrodes, instead of standard vertical Micro-Strip electrodes. The in-plane CMS driving electrodes have both low radio frequency (RF) losses and high overlap integral between optical and RF waves compared to the vertical designs. Since the optical waveguide and CMS electrodes are located in the same plane, optical injection and microwave driving access cannot be separated perpendicularly without intersection between them. A via-less transition between grounded coplanar waveguide access and CMS driving electrodes is introduced in order to provide broadband excitation of optical phase modulators and avoid the intersection of the optical core and the electrical probe. Simulation and measurement results of the benzocyclobutene polymer as a cladding material and the PMMI-CPO1 polymer as an optical core with an electro-optic coefficient of 70 pm/V demonstrate a broadband operation of 67 GHz using travelling-wave driving electrodes with a half-wave voltage of 4.5 V, while satisfying its low RF losses and high overlap integral between optical and RF waves of in-plane CMS electrodes.
Unusual strategies for using indium gallium nitride grown on silicon (111) for solid-state lighting
Kim, Hoon-sik; Brueckner, Eric; Song, Jizhou; Li, Yuhang; Kim, Seok; Lu, Chaofeng; Sulkin, Joshua; Choquette, Kent; Huang, Yonggang; Nuzzo, Ralph G.; Rogers, John A.
2011-01-01
Properties that can now be achieved with advanced, blue indium gallium nitride light emitting diodes (LEDs) lead to their potential as replacements for existing infrastructure in general illumination, with important implications for efficient use of energy. Further advances in this technology will benefit from reexamination of the modes for incorporating this materials technology into lighting modules that manage light conversion, extraction, and distribution, in ways that minimize adverse thermal effects associated with operation, with packages that exploit the unique aspects of these light sources. We present here ideas in anisotropic etching, microscale device assembly/integration, and module configuration that address these challenges in unconventional ways. Various device demonstrations provide examples of the capabilities, including thin, flexible lighting “tapes” based on patterned phosphors and large collections of small light emitters on plastic substrates. Quantitative modeling and experimental evaluation of heat flow in such structures illustrates one particular, important aspect of their operation: small, distributed LEDs can be passively cooled simply by direct thermal transport through thin-film metallization used for electrical interconnect, providing an enhanced and scalable means to integrate these devices in modules for white light generation. PMID:21666096
NASA Astrophysics Data System (ADS)
Williams, David J.
The present volume on nonlinear optical properties of organic materials discusses organic nonlinear optics, polymers for nonlinear optics, characterization of nonlinear properties, photorefractive and second-order materials, harmonic generation in organic materials, and devices and applications. Particular attention is given to organic semiconductor-doped polymer glasses as novel nonlinear media, heterocyclic nonlinear optical materials, loss measurements in electrooptic polymer waveguides, the phase-matched second-harmonic generation in planar waveguides, electrooptic measurements in poled polymers, transient effects in spatial light modulation by nonlinearity-absorbing molecules, the electrooptic effects in organic single crystals, surface acoustic wave propagation in an organic nonlinear optical crystal, nonlinear optics of astaxanthin thin films; and advanced high-temperature polymers for integrated optical waveguides. (No individual items are abstracted in this volume)
Integrated residential photovoltaic array development
NASA Astrophysics Data System (ADS)
Shepard, N. F., Jr.
1981-02-01
An optimum integrated residential photovoltaic array/module is addressed. Nineteen existing or proposed systems intended for residential applications are described. Each of these systems is rated against a comprehensive set of evaluation criteria in an effort to formulate three module design concepts for further study and analysis. This evaluation led to a number of observations which are enumerated and should be considered in future module and array designs. Three module concepts are presented as baseline design approaches to be further analyzed and optimized. These options include: (1) a rectangular, direct mounted, shingle type module; (2) an integrally mounted module with nonconductive exposed elements; and (3) an aluminum framed, stand off module. Preliminary design drawings are presented for each of these module configurations.
Integrated residential photovoltaic array development
NASA Technical Reports Server (NTRS)
Shepard, N. F., Jr.
1981-01-01
An optimum integrated residential photovoltaic array/module is addressed. Nineteen existing or proposed systems intended for residential applications are described. Each of these systems is rated against a comprehensive set of evaluation criteria in an effort to formulate three module design concepts for further study and analysis. This evaluation led to a number of observations which are enumerated and should be considered in future module and array designs. Three module concepts are presented as baseline design approaches to be further analyzed and optimized. These options include: (1) a rectangular, direct mounted, shingle type module; (2) an integrally mounted module with nonconductive exposed elements; and (3) an aluminum framed, stand off module. Preliminary design drawings are presented for each of these module configurations.
Thermal-structural design study of an airframe-integrated Scramjet
NASA Technical Reports Server (NTRS)
Killackey, J. J.; Katinsky, E. A.; Tepper, S.; Vuigner, A. A.
1978-01-01
Design concepts are developed and evaluated for a cooled structures assembly for the Scramjet engine, for engine subsystems mass, volume, and operating requirements, and for the aircraft/engine interface. A thermal protection system was defined that makes it possible to attain a life of 100 hours and 1000 cycles. The coolant equivalence ratio at the Mach 10 maximum thermal loading condition is 0.6, indicating a capacity for airframe cooling. The mechanical design is feasible for manufacture using conventional materials. For the cooled structures in a six-module engine, the mass per unit capture area is 12.4 KN/sq m. The total weight of a six-module engine assembly including the fuel system is 14.73 KN.
Integration of hybrid silicon lasers and electroabsorption modulators.
Sysak, Matthew N; Anthes, Joel O; Bowers, John E; Raday, Omri; Jones, Richard
2008-08-18
We present an integration platform based on quantum well intermixing for multi-section hybrid silicon lasers and electroabsorption modulators. As a demonstration of the technology, we have fabricated discrete sampled grating DBR lasers and sampled grating DBR lasers integrated with InGaAsP/InP electroabsorption modulators. The integrated sampled grating DBR laser-modulators use the as-grown III-V bandgap for optical gain, a 50 nm blue shifted bandgap for the electrabosprtion modulators, and an 80 nm blue shifted bandgap for low loss mirrors. Laser continuous wave operation up to 45 ?C is achieved with output power >1.0 mW and threshold current of <50 mA. The modulator bandwidth is >2GHz with 5 dB DC extinction.
MISPS: Module integrated solar position sensor for concentration photovoltaics
NASA Astrophysics Data System (ADS)
Pardell, Ricard
2012-10-01
This paper describes a new device, the MISPS (Module Integrated. Solar Position Sensor) for CPV systems. Its main innovation lies in it being module integrated, so that the sensor is a constituent part of the module and uses its optics. The MISPS has been designed within the scope of the CPVRS project, but it can be used in any refractive optics CPV system.
Switchable Scattering Meta-Surfaces for Broadband Terahertz Modulation
Unlu, M.; Hashemi, M. R.; Berry, C. W.; Li, S.; Yang, S.-H.; Jarrahi, M.
2014-01-01
Active tuning and switching of electromagnetic properties of materials is of great importance for controlling their interaction with electromagnetic waves. In spite of their great promise, previously demonstrated reconfigurable metamaterials are limited in their operation bandwidth due to their resonant nature. Here, we demonstrate a new class of meta-surfaces that exhibit electrically-induced switching in their scattering parameters at room temperature and over a broad range of frequencies. Structural configuration of the subwavelength meta-molecules determines their electromagnetic response to an incident electromagnetic radiation. By reconfiguration of the meta-molecule structure, the strength of the induced electric field and magnetic field in the opposite direction to the incident fields are varied and the scattering parameters of the meta-surface are altered, consequently. We demonstrate a custom-designed meta-surface with switchable scattering parameters at a broad range of terahertz frequencies, enabling terahertz intensity modulation with record high modulation depths and modulation bandwidths through a fully integrated, voltage-controlled device platform at room temperature. PMID:25028123
Ke, Yujie; Balin, Igal; Wang, Ning; Lu, Qi; Tok, Alfred Iing Yoong; White, Timothy J; Magdassi, Shlomo; Abdulhalim, Ibrahim; Long, Yi
2016-12-07
Two-dimensional (2D) photonic structures, widely used for generating photonic band gaps (PBG) in a variety of materials, are for the first time integrated with the temperature-dependent phase change of vanadium dioxide (VO 2 ). VO 2 possesses thermochromic properties, whose potential remains unrealized due to an undesirable yellow-brown color. Here, a SiO 2 /VO 2 core/shell 2D photonic crystal is demonstrated to exhibit static visible light tunability and dynamic near-infrared (NIR) modulation. Three-dimensional (3D) finite difference time domain (FDTD) simulations predict that the transmittance can be tuned across the visible spectrum, while maintaining good solar regulation efficiency (ΔT sol = 11.0%) and high solar transmittance (T lum = 49.6%). Experiments show that the color changes of VO 2 films are accompanied by NIR modulation. This work presents a novel way to manipulate VO 2 photonic structures to modulate light transmission as a function of wavelength at different temperatures.
First Materials Science Research Rack Capabilities and Design Features
NASA Technical Reports Server (NTRS)
Schaefer, D.; King, R.; Cobb, S.; Whitaker, Ann F. (Technical Monitor)
2001-01-01
The first Materials Science Research Rack (MSRR-1) will accommodate dual Experiment Modules (EM's) and provide simultaneous on-orbit processing operations capability. The first international Materials Science Experiment Module for the MSRR-1 is an international cooperative research activity between NASA's Marshall Space Flight Center (MSFC) and the European Space Agency's (ESA) European Space Research and Technology Center. (ESTEC). This International Standard Payload Rack (ISPR) will contain the Materials Science Laboratory (MSL) developed by ESA as an Experiment Module. The MSL Experiment Module will accommodate several on-orbit exchangeable experiment-specific Module Inserts. Module Inserts currently planned are a Quench Module Insert, Low Gradient Furnace, Solidification with Quench Furnace, and Diffusion Module Insert. The second Experiment Module for the MSRR-1 configuration is a commercial device supplied by MSFC's Space Products Department (SPD). It includes capabilities for vapor transport processes and liquid metal sintering. This Experiment Module will be replaced on-orbit with other NASA Materials Science EMs.
Ferroelectric thin-film capacitors and piezoelectric switches for mobile communication applications.
Klee, Mareike; van Esch, Harry; Keur, Wilco; Kumar, Biju; van Leuken-Peters, Linda; Liu, Jin; Mauczok, Rüdiger; Neumann, Kai; Reimann, Klaus; Renders, Christel; Roest, Aarnoud L; Tiggelman, Mark P J; de Wild, Marco; Wunnicke, Olaf; Zhao, Jing
2009-08-01
Thin-film ferroelectric capacitors have been integrated with resistors and active functions such as ESD protection into small, miniaturized modules, which enable a board space saving of up to 80%. With the optimum materials and processes, integrated capacitors with capacitance densities of up to 100 nF/mm2 for stacked capacitors combined with breakdown voltages of 90 V have been achieved. The integration of these high-density capacitors with extremely high breakdown voltage is a major accomplishment in the world of passive components and has not yet been reported for any other passive integration technology. Furthermore, thin-film tunable capacitors based on barium strontium titanate with high tuning range and high quality factor at 1 GHz have been demonstrated. Finally, piezoelectric thin films for piezoelectric switches with high switching speed have been realized.
Modular-based multiscale modeling on viscoelasticity of polymer nanocomposites
NASA Astrophysics Data System (ADS)
Li, Ying; Liu, Zeliang; Jia, Zheng; Liu, Wing Kam; Aldousari, Saad M.; Hedia, Hassan S.; Asiri, Saeed A.
2017-02-01
Polymer nanocomposites have been envisioned as advanced materials for improving the mechanical performance of neat polymers used in aerospace, petrochemical, environment and energy industries. With the filler size approaching the nanoscale, composite materials tend to demonstrate remarkable thermomechanical properties, even with addition of a small amount of fillers. These observations confront the classical composite theories and are usually attributed to the high surface-area-to-volume-ratio of the fillers, which can introduce strong nanoscale interfacial effect and relevant long-range perturbation on polymer chain dynamics. Despite decades of research aimed at understanding interfacial effect and improving the mechanical performance of composite materials, it is not currently possible to accurately predict the mechanical properties of polymer nanocomposites directly from their molecular constituents. To overcome this challenge, different theoretical, experimental and computational schemes will be used to uncover the key physical mechanisms at the relevant spatial and temporal scales for predicting and tuning constitutive behaviors in silico, thereby establishing a bottom-up virtual design principle to achieve unprecedented mechanical performance of nanocomposites. A modular-based multiscale modeling approach for viscoelasticity of polymer nanocomposites has been proposed and discussed in this study, including four modules: (A) neat polymer toolbox; (B) interphase toolbox; (C) microstructural toolbox and (D) homogenization toolbox. Integrating these modules together, macroscopic viscoelasticity of polymer nanocomposites could be directly predicted from their molecular constituents. This will maximize the computational ability to design novel polymer composites with advanced performance. More importantly, elucidating the viscoelasticity of polymer nanocomposites through fundamental studies is a critical step to generate an integrated computational material engineering principle for discovering and manufacturing new composites with transformative impact on aerospace, automobile, petrochemical industries.
Influences of Nozzle Material on Laser Droplet Brazing Joints with Cu89Sn11 Preforms
NASA Astrophysics Data System (ADS)
Stein, Stefan; Heberle, Johannes; Gürtler, Franz Josef; Cvecek, Kristian; Roth, Stephan; Schmidt, Michael
This paper presents latest results on the influences of nozzle material and geometry on the electromechanical contacting of sensitive piezoceramic actuator modules. Two nozzle types have been investigated,a standard WC/Co nozzle which is used for soldering applications and a novelceramic nozzle. Applications for active piezoceramic components integrated in structural parts are e.g. active damping, energy harvesting, or monitoring of vibrations and material failure. Anup to now unsolved problem is the electrical contacting of such components without damaging the conductor or the metallization of the ceramic substrate. Since piezoelectric components are to be integrated into structures made of casted aluminum, requirements are high mechanical strength and temperature resistance. Within this paper a method forcontacting piezoceramic modules is presented. A spherical braze preform of tin bronze Cu89Sn11 with a diameter of 600 μm is located in a ceramic nozzle and is subsequently melted by a laser pulse. The liquid solder is ejected from the nozzlevia nitrogen overpressure and wets the surface of the metallization pad and the Cu-wire, resulting in a brazing joint after solidification. The process is called laser droplet brazing (LDB). To asses the thermal evolution during one cycle WC/Co and ZTA have been simulated numerically for two different geometries enabling a proposition weather the geometry or the material properties have a significant influence on the thermal load during one cycle. To evaluate the influence of the nozzle on the joint the positioning accuracy, joint height and detachment times have been evaluated. Results obtained with the ZTA nozzle show comparable positioning accuracies to a WC/Co nozzle with a lower standard deviation of solder detachment time.
Silicon photonics devices for metro applications
NASA Astrophysics Data System (ADS)
Fukuda, H.; Kikuchi, K.; Jizodo, M.; Kawamura, Y.; Takeda, K.; Honda, K.
2017-01-01
Digital coherent technology is considered an attractive way of realizing both high-speed metro links and long distance transmissions. In metro areas, there is a strong demand for a smaller, faster transceiver module. This demand is mainly driven by the rapidly increasing data center interconnection traffic, where transmission capacity per faceplane is a key feature. Therefore, optical integration technology is desired. Since compensation in digital coherent technology is performed in the electrical or digital domain, users can deal with those optics performances that are not compensated for digitally. This means using a new material that cannot provide perfect characteristics but that is suitable for miniaturization and integration is possible. Silicon photonics (SiPh) is considered an attractive technology that would enable the significant miniaturization of optical circuits and be capable of optical integration with high manufacturability. While SiPh-based devices have begun to be deployed for very short or short reach links on the basis of direct detection technology, their digital coherent applications have recently been investigated in view of their integration capability. This paper describes recent progress on SiPh-based integrated optical devices for high-speed digital coherent transceivers targeting metro links. An optical modulator and receiver with related circuits have been integrated into a single SiPh chip. TEC-free operation under non-hermetic conditions and the direct attachment of optical fibers have both been realized. Very thin and small packaging with sufficient performance has been demonstrated by using the SiPh chip co-packaged with high-speed ICs.
JSUS solar thermal thruster and its integration with thermionic power converter
NASA Astrophysics Data System (ADS)
Shimizu, Morio; Eguchi, Kunihisa; Itoh, Katsuya; Sato, Hitoshi; Fujii, Tadayuki; Okamoto, Ken-Ichi; Igarashi, Tadashi
1998-01-01
This paper describes solar heating test results of a single crystal Mo thruster of solar thermal propulsion (STP) with super high-temperature brazing of Mo/Ru for hydrogen-gas sealing, using the paraboloidal concentrator of 1.6 m diameter newly installed in NAL in the Japan Solar Upper Stage (JSUS) research program. The designed thruster has a target Isp about 800 sec for 2,250 K or higher temperatures of hydrogen propellant. Additionally, tungsten CVD-coating was applied to a outer surface of the thruster in order to prevent vaporization of the wall material and Mo/Ru under the condition of high temperature over 2,500K and high vacuum. Also addressed in our paper is solar thermionic power module design for the integration with the STP receiver. The thermionic converter (TIC) module is of a planar type in a Knudsen-mode operation and provides a high conversion efficiency of 23% at the TIC emitter temperature of nearly 1,850 K for a heat input flux of 24 W/cm2.
Alternative technological development for RF hybridization
NASA Astrophysics Data System (ADS)
Antônio Finardi, Célio; da Fontoura Ponchet, André; Battesini Adamo, Cristina; Flacker, Alexander; Cotrin Teixeira, Ricardo; Panepucci, Roberto Ricardo
2017-03-01
The paper presents a technological solution for high frequency packaging platform evaluated up to 40 GHz. The main purpose of this development was to define an alternative hybrid technology that is more flexible and faster to prototype compared with thin film or multi chip module (MCM-D). The alternative technology also shows adequate performance for high bit rate solutions integrating optical and electronics blocks. This approach consists of a soft substrate (laminate material), plating processes (electroless Ni-P/Au, electrolytic Au) and lithography patterning. Ground coplanar waveguide was used for microwave structures with excellent ground planes connections due to easy via holes implementation. We present results of high frequency packaging of important RF blocks, such as integrated broadband bias-T, transimpedance amplifier ICs and silicon photonics optical modulators. The paper demonstrates a solution for high frequency hybridization that can be implemented with standard substrates, designed with any shape and with large numbers of metalized via holes and compatible with usual assembling techniques.
NASA Astrophysics Data System (ADS)
Pratt-Sitaula, B.; Charlevoix, D. J.; Douglas, B. J.; Crosby, B. T.; Crosby, C. J.; Lauer, I. H.; Shervais, K.
2017-12-01
Field experiences have long been considered an integral part of geoscience learning. However, as data acquisition technologies evolve, undergraduate field courses need to keep pace so students gain exposure to new technologies relevant to the modern workforce. Maintaining expertise on new technologies is also challenging to established field education programs. Professional development and vetted curriculum present an opportunity to advance student exposure to new geoscience data acquisition technology. The GEodesy Tools for Societal Issues (GETSI) Field Collection, funded by NSF's Improving Undergraduate STEM Education program, addresses these needs in geodesy field education. Geodesy is the science of accurately measuring Earth's size, shape, orientation, mass distribution and the variations of these with time. Modern field geodesy methods include terrestrial laser scanning (TLS), kinematic and static GPS/GNSS surveying (global positioning system/global navigation satellite system), and structure from motion (SfM) photogrammetry. The GETSI Field Collection is a collaborative project between UNAVCO, Indiana University, and Idaho State University. The project is provides curriculum modules and instructor training (in the form of short courses) to facilitate the inclusion of SfM, TLS, and GPS surveying into geoscience courses with field components. The first module - Analyzing High Resolution Topography with TLS and SfM - is available via SERC; (serc.carleton.edu/getsi/teaching_materials/high-rez-topo) the second module - "High Precision Positioning with Static and Kinematic GPS/GNSS" - will be published in 2018. The module development and assessment follows the standards of the InTeGrate Project (an NSF STEP Center)previously tested on geodesy content in the GETSI classroom collection (serc.carleton.edu/getsi). This model emphasizes use of best practices in STEM education, including situating learning in the context of societal importance. Analysis of student work during development and testing shows a high level of achievement of module learning goals. Two four-day short courses have been run to train instructors on best practices for integration of these topics into field courses. Overall participant satisfaction with the short courses has been 9 out of 10.
A comprehensive strategy for designing a Web-based medical curriculum.
Zucker, J.; Chase, H.; Molholt, P.; Bean, C.; Kahn, R. M.
1996-01-01
In preparing for a full featured online curriculum, it is necessary to develop scaleable strategies for software design that will support the pedagogical goals of the curriculum and which will address the issues of acquisition and updating of materials, of robust content-based linking, and of integration of the online materials into other methods of learning. A complete online curriculum, as distinct from an individual computerized module, must provide dynamic updating of both content and structure and an easy pathway from the professor's notes to the finished online product. At the College of Physicians and Surgeons, we are developing such strategies including a scripted text conversion process that uses the Hypertext Markup Language (HTML) as structural markup rather than as display markup, automated linking by the use of relational databases and the Unified Medical Language System (UMLS), integration of text, images, and multimedia along with interface designs which promote multiple contexts and collaborative study. PMID:8947624
Silicon-graphene photonic devices
NASA Astrophysics Data System (ADS)
Yin, Yanlong; Li, Jiang; Xu, Yang; Tsang, Hon Ki; Dai, Daoxin
2018-06-01
Silicon photonics has attracted much attention because of the advantages of CMOS (complementary-metal-oxide-semiconductor) compatibility, ultra-high integrated density, etc. Great progress has been achieved in the past decades. However, it is still not easy to realize active silicon photonic devices and circuits by utilizing the material system of pure silicon due to the limitation of the intrinsic properties of silicon. Graphene has been regarded as a promising material for optoelectronics due to its unique properties and thus provides a potential option for realizing active photonic integrated devices on silicon. In this paper, we present a review on recent progress of some silicon-graphene photonic devices for photodetection, all-optical modulation, as well as thermal-tuning. Project supported by the National Major Research and Development Program (No. 2016YFB0402502), the National Natural Science Foundation of China (Nos. 11374263, 61422510, 61431166001, 61474099, 61674127), and the National Key Research and Development Program (No. 2016YFA0200200).
Optics Communications: Special issue on Polymer Photonics and Its Applications
NASA Astrophysics Data System (ADS)
Zhang, Ziyang; Pitwon, Richard C. A.; Feng, Jing
2016-03-01
In the last decade polymer photonics has witnessed a tremendous boost in research efforts and practical applications. Polymer materials can be engineered to exhibit unique optical and electrical properties. Extremely transparent and reliable passive optical polymers have been made commercially available and paved the ground for the development of various waveguide components. Advancement in the research activities regarding the synthesis of active polymers has enabled devices such as ultra-fast electro-optic modulators, efficient white light emitting diodes, broadband solar cells, flexible displays, and so on. The fabrication technology is not only fast and cost-effective, but also provides flexibility and broad compatibility with other semiconductor processing technologies. Reports show that polymers have been integrated in photonic platforms such as silicon-on-insulator (SOI), III-V semiconductors, and silica PLCs, and vice versa, photonic components made from a multitude of materials have been integrated, in a heterogeneous/hybrid manner, in polymer photonic platforms.
A hybrid electronically scanned pressure module for cryogenic environments
NASA Technical Reports Server (NTRS)
Chapman, J. J.; Hopson, P., Jr.; Kruse, N.
1995-01-01
Pressure is one of the most important parameters measured when testing models in wind tunnels. For models tested in the cryogenic environment of the National Transonic Facility at NASA Langley Research Center, the technique of utilizing commercially available multichannel pressure modules inside the models is difficult due to the small internal volume of the models and the requirement of keeping the pressure transducer modules within an acceptable temperature range well above the -173 degrees C tunnel temperature. A prototype multichannel pressure transducer module has been designed and fabricated with stable, repeatable sensors and materials optimized for reliable performance in the cryogenic environment. The module has 16 single crystal silicon piezoresistive pressure sensors electrostatically bonded to a metalized Pyrex substrate for sensing the wind tunnel model pressures. An integral temperature sensor mounted on each silicon micromachined pressure sensor senses real-time temperature fluctuations to within 0.1 degrees C to correct for thermally induced non-random sensor drift. The data presented here are from a prototype sensor module tested in the 0.3 M cryogenic tunnel and thermal equilibrium conditions in an environmental chamber which approximates the thermal environment (-173 degrees C to +60 degrees C) of the National Transonic Facility.
Optical integration of SPO mirror modules in the ATHENA telescope
NASA Astrophysics Data System (ADS)
Valsecchi, G.; Marioni, F.; Bianucci, G.; Zocchi, F. E.; Gallieni, D.; Parodi, G.; Ottolini, M.; Collon, M.; Civitani, M.; Pareschi, G.; Spiga, D.; Bavdaz, M.; Wille, E.
2017-08-01
ATHENA (Advanced Telescope for High-ENergy Astrophysics) is the next high-energy astrophysical mission selected by the European Space Agency for launch in 2028. The X-ray telescope consists of 1062 silicon pore optics mirror modules with a target angular resolution of 5 arcsec. Each module must be integrated on a 3 m structure with an accuracy of 1.5 arcsec for alignment and assembly. This industrial and scientific team is developing the alignment and integration process of the SPO mirror modules based on ultra-violet imaging at the 12 m focal plane. This technique promises to meet the accuracy requirement while, at the same time, allowing arbitrary integration sequence and mirror module exchangeability. Moreover, it enables monitoring the telescope point spread function during the planned 3-year integration phase.
A W-band integrated power module using MMIC MESFET power amplifiers and varactor doublers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ho, T.C.; Chen, Seng Woon; Pande, K.
1993-12-01
A high-performance integrated power module using U-band MMIC MESFET power amplifiers in conjunction with W-band MMIC high efficiency varactor doublers has been developed for millimeter-wave system applications. This paper presents the design, fabrication, and performance of this W-band integrated power module. Measured results of the complete integrated power module show an output power of 90 mW with an overall associated gain of 29.5 dB at 94 GHz. A saturated power of over 95 mW was also achieved. These results represent the highest reported power and gain at W-band using MESFET and varactor frequency doubling technologies. This integrated power module ismore » suitable for the future 94 GHz missile seeker applications.« less
NASA Astrophysics Data System (ADS)
Brand, B. D.; McMullin-Messier, P. A.; Schlegel, M. E.
2014-12-01
'Map your Hazards' is an educational module developed within the NSF Interdisciplinary Teaching about Earth for a Sustainable Future program (InTeGrate). The module engages students in place-based explorations of natural hazards, social vulnerability, and the perception of natural hazards and risk. Students integrate geoscience and social science methodologies to (1) identify and assess hazards, vulnerability and risk within their communities; (2) distribute, collect and evaluate survey data (designed by authors) on the knowledge, risk perception and preparedness within their social networks; and (3) deliver a PPT presentation to local stakeholders detailing their findings and recommendations for development of a prepared, resilient community. 'Map your Hazards' underwent four rigorous assessments by a team of geoscience educators and external review before being piloted in our classrooms. The module was piloted in a 300-level 'Volcanoes and Society' course at Boise State University, a 300-level 'Environmental Sociology' course at Central Washington University, and a 100-level 'Natural Disasters and Environmental Geology' course at the College of Western Idaho. In all courses students reported a fascination with learning about the hazards around them and identifying the high risk areas in their communities. They were also surprised at the low level of knowledge, inaccurate risk perception and lack of preparedness of their social networks. This successful approach to engaging students in an interdisciplinary, place-based learning environment also has the broad implications of raising awareness of natural hazards (survey participants are provided links to local hazard and preparedness information). The data and preparedness suggestions can be shared with local emergency managers, who are encouraged to attend the student's final presentations. All module materials are published at serc.carleton.edu/integrate/ and are appropriate to a wide range of classrooms.
2012-05-01
field-programmable gate array (FPGA) uses digital signal processing (DSP) algorithms to decode echo-location information from the backscattered signal ...characterizing and understanding of the physical properties of the BST and PZT thin films. Using microwave reflection spectroscopy, the complex...acoustic data, , would be encoded in the reflected MW signal by means of phase modulation (PM). By using high-Q resonators as the reactive
Ford poses at the FIR/LMM/ACE in the U.S. Laboratory
2013-02-21
ISS034-E-056144 (21 Feb. 2013) --- Inside the U.S. Laboratory (Destiny) aboard the Earth-orbiting International Space Statio, NASA astronaut Kevin Ford, Expedition 34 commander, is seen with the Fluids Integration Rack (FIR)/Light Microscopy Module (LMM)/Advanced Colloids Experiment (ACE). ACE samples, which produce microscopic images of materials containing small colloidal particles, are scheduled for arrival on SpaceX-2 in the first week of March.
2013-06-24
In the International Space Stations Destiny laboratory,NASA astronaut Karen Nyberg,Expedition 36 flight engineer,speaks into a microphone while conducting a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.
Passive Isolators for use on the International Space Station
NASA Technical Reports Server (NTRS)
Houston, Janice; Gattis, Christy
2003-01-01
The value of the International Space Station (ISS) as a premier microgravity environment is currently at risk due to structure-borne vibration. The vibration sources are varied and include crew activities such as exercising or simply moving from module to module, and electro- mechanical equipment such as fans and pumps. Given such potential degradation of usable microgravity, anything that can be done to dampen vibration on-orbit will significantly benefit microgravity users. Most vibration isolation schemes, both active and passive, have proven to be expensive - both operationally and from the cost of integrating isolation systems into primary/secondary structural interfaces (e.g., the ISS module/rack interface). Recently, passively absorptive materials have been tested at the bolt interfaces between the operating equipment and support structure (secondary/tertiary structural interfaces). The results indicate that these materials may prove cost-effective in mitigating the vibrational problems of the ISS. We report herein tests of passive absorbers placed at the interface of a vibration-inducing component: the Development Distillation Assembly, a subassembly of the Urine Processing Assembly, which is a rotating centrifuge and cylinder assembly attached to a mounting plate. Passive isolators were installed between this mounting plate and its support shelf. Three materials were tested: BISCO HT-800, Sorbothane 30 and Sorbothane 50, plus a control test with a hard shim. In addition, four distinct combinations of the HT-800 and Sorbothane 50 were tested. Results show a significant (three orders of magnitude) reduction of transmitted energy, as measured in power spectral density (PSD), using the isolation materials. It is noted, however, that passive materials cannot prevent the transmission of very strong forces or absorb the total energy induced from structural resonances.
Measurement of thermal conductivity and thermal diffusivity using a thermoelectric module
NASA Astrophysics Data System (ADS)
Beltrán-Pitarch, Braulio; Márquez-García, Lourdes; Min, Gao; García-Cañadas, Jorge
2017-04-01
A proof of concept of using a thermoelectric module to measure both thermal conductivity and thermal diffusivity of bulk disc samples at room temperature is demonstrated. The method involves the calculation of the integral area from an impedance spectrum, which empirically correlates with the thermal properties of the sample through an exponential relationship. This relationship was obtained employing different reference materials. The impedance spectroscopy measurements are performed in a very simple setup, comprising a thermoelectric module, which is soldered at its bottom side to a Cu block (heat sink) and thermally connected with the sample at its top side employing thermal grease. Random and systematic errors of the method were calculated for the thermal conductivity (18.6% and 10.9%, respectively) and thermal diffusivity (14.2% and 14.7%, respectively) employing a BCR724 standard reference material. Although errors are somewhat high, the technique could be useful for screening purposes or high-throughput measurements at its current state. This new method establishes a new application for thermoelectric modules as thermal properties sensors. It involves the use of a very simple setup in conjunction with a frequency response analyzer, which provides a low cost alternative to most of currently available apparatus in the market. In addition, impedance analyzers are reliable and widely spread equipment, which facilities the sometimes difficult access to thermal conductivity facilities.
Papadakis, G; Friedt, J M; Eck, M; Rabus, D; Jobst, G; Gizeli, E
2017-09-01
The development of integrated platforms incorporating an acoustic device as the detection element requires addressing simultaneously several challenges of technological and scientific nature. The present work was focused on the design of a microfluidic module, which, combined with a dual or array type Love wave acoustic chip could be applied to biomedical applications and molecular diagnostics. Based on a systematic study we optimized the mechanics of the flow cell attachment and the sealing material so that fluidic interfacing/encapsulation would impose minimal losses to the acoustic wave. We have also investigated combinations of operating frequencies with waveguide materials and thicknesses for maximum sensitivity during the detection of protein and DNA biomarkers. Within our investigations neutravidin was used as a model protein biomarker and unpurified PCR amplified Salmonella DNA as the model genetic target. Our results clearly indicate the need for experimental verification of the optimum engineering and analytical parameters, in order to develop commercially viable systems for integrated analysis. The good reproducibility of the signal together with the ability of the array biochip to detect multiple samples hold promise for the future use of the integrated system in a Lab-on-a-Chip platform for application to molecular diagnostics.
Method and apparatus for assessing material properties of sheet-like materials
Telschow, Kenneth L.; Deason, Vance A.
2002-01-01
Apparatus for producing an indication of a material property of a sheet-like material according to the present invention may comprise an excitation source for vibrating the sheet-like material to produce at least one traveling wave therein. A light source configured to produce an object wavefront and a reference wavefront directs the object wavefront toward the sheet-like material to produce a modulated object wavefront. A modulator operatively associated with the reference wavefront modulates the reference wavefront in synchronization with the traveling wave on the sheet-like material to produce a modulated reference wavefront. A sensing medium positioned to receive the modulated object wavefront and the modulated reference wavefront produces an image of the traveling wave in the sheet-like material, the image of the anti-symmetric traveling wave being related to a displacement amplitude of the anti-symmetric traveling wave over a two-dimensional area of the vibrating sheet-like material. A detector detects the image of the traveling wave in the sheet-like material.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bolotnikov, A. E.; Ackley, K.; Camarda, G. S.
We developed a robust and low-cost array of virtual Frisch-grid CdZnTe (CZT) detectors coupled to a front-end readout ASIC for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6x6x15 mm 3 detectors grouped into 3x3 sub-arrays of 2x2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readoutmore » electronics. The further enhancement of the arrays’ performance and reduction of their cost are made possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.« less
High Fidelity Tape Transfer Printing Based On Chemically Induced Adhesive Strength Modulation
NASA Astrophysics Data System (ADS)
Sim, Kyoseung; Chen, Song; Li, Yuhang; Kammoun, Mejdi; Peng, Yun; Xu, Minwei; Gao, Yang; Song, Jizhou; Zhang, Yingchun; Ardebili, Haleh; Yu, Cunjiang
2015-11-01
Transfer printing, a two-step process (i.e. picking up and printing) for heterogeneous integration, has been widely exploited for the fabrication of functional electronics system. To ensure a reliable process, strong adhesion for picking up and weak or no adhesion for printing are required. However, it is challenging to meet the requirements of switchable stamp adhesion. Here we introduce a simple, high fidelity process, namely tape transfer printing(TTP), enabled by chemically induced dramatic modulation in tape adhesive strength. We describe the working mechanism of the adhesion modulation that governs this process and demonstrate the method by high fidelity tape transfer printing several types of materials and devices, including Si pellets arrays, photodetector arrays, and electromyography (EMG) sensors, from their preparation substrates to various alien substrates. High fidelity tape transfer printing of components onto curvilinear surfaces is also illustrated.
Liu, Xiaochi; Qu, Deshun; Li, Hua-Min; Moon, Inyong; Ahmed, Faisal; Kim, Changsik; Lee, Myeongjin; Choi, Yongsuk; Cho, Jeong Ho; Hone, James C; Yoo, Won Jong
2017-09-26
Diverse diode characteristics were observed in two-dimensional (2D) black phosphorus (BP) and molybdenum disulfide (MoS 2 ) heterojunctions. The characteristics of a backward rectifying diode, a Zener diode, and a forward rectifying diode were obtained from the heterojunction through thickness modulation of the BP flake or back gate modulation. Moreover, a tunnel diode with a precursor to negative differential resistance can be realized by applying dual gating with a solid polymer electrolyte layer as a top gate dielectric material. Interestingly, a steep subthreshold swing of 55 mV/dec was achieved in a top-gated 2D BP-MoS 2 junction. Our simple device architecture and chemical doping-free processing guaranteed the device quality. This work helps us understand the fundamentals of tunneling in 2D semiconductor heterostructures and shows great potential in future applications in integrated low-power circuits.
Integrated modular teaching in dermatology for undergraduate students: A novel approach.
Karthikeyan, Kaliaperumal; Kumar, Annapurna
2014-07-01
Undergraduate teaching in dermatology comprises didactic lectures and clinical classes. Integrated modular teaching is a novel approach, which integrates basic sciences with dermatology in the form of a module. Further the module also incorporates various teaching modalities, which facilitate active participation from students and promotes learning. The pre- and post-test values showed the effectiveness of the integrated module. The students feedback was encouraging. The aim of this study was to determine the acceptance and opinion of undergraduate students regarding integrated modular teaching as a new teaching aid in dermatology. This was a descriptive study. Varied teaching methodologies involving multiple disciplines were undertaken in six major undergraduate topics in dermatology for seventh and eighth semester students. A total of six modules were conducted over a period of 12 months for students of seventh and eighth semesters. The topics for the various modules were sexually transmitted diseases, acquired immunodeficiency syndrome, oral ulcers, leprosy, connective tissue disorders and psoriasis. Faculty members from different disciplines participated. Pre- and post-test were conducted before and after the modules respectively to gauge the effectiveness of the modules. It was found that almost every student had a better score on the posttest as compared to the pretest. General feedback obtained from the students showed that all of them felt that modular teaching was a more interesting and useful teaching learning experience than conventional teaching. Integrated modular teaching can be an effective adjunct in imparting theoretical and practical knowledge to the students. Further, various teaching methodologies can be used in integrated modules effectively with active student participation. Thus integrated modular teaching addresses two important issues in medical education, namely integration and active student participation.
Transceivers and receivers for quantum key distribution and methods pertaining thereto
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeRose, Christopher; Sarovar, Mohan; Soh, Daniel B.S.
Various technologies for performing continuous-variable (CV) and discrete-variable (DV) quantum key distribution (QKD) with integrated electro-optical circuits are described herein. An integrated DV-QKD system uses Mach-Zehnder modulators to modulate a polarization of photons at a transmitter and select a photon polarization measurement basis at a receiver. An integrated CV-QKD system uses wavelength division multiplexing to send and receive amplitude-modulated and phase-modulated optical signals with a local oscillator signal while maintaining phase coherence between the modulated signals and the local oscillator signal.
Mazzola, Rosario; Ricchetti, Francesco; Fiorentino, Alba; Levra, Niccolò Giaj; Fersino, Sergio; Di Paola, Gioacchino; Ruggieri, Ruggero
2016-01-01
Background: To evaluate the feasibility and clinical preliminary results of weekly cisplatin and volumetric-modulated arc therapy to the pelvis with simultaneous integrated boost to macroscopic disease in a cohort of elderly patients. Materials and Methods: Inclusion criteria of this prospective study were age ≥70 years, Karnofsky performance status 70 to 100, locally advanced histologically proven squamous cervical carcinoma, and patients unable to undergo brachytherapy. Radiation doses prescribed were 66 Gy to the macroscopic disease and 54 Gy to the pelvic nodes in 30 fractions. Weekly cisplatin dose was 40 mg/mq. Results: A total of 30 patients were recruited. Median follow-up was 32 months (range: 8-48 months). Median age was 72 years (range: 70-84 years). The 3-year overall survival and local control were 93% and 80%, respectively. The median time to progression was 24 months (range: 6-30 months). Analyzing clinical outcome grouping based on the stage of disease, II versus III, the 3-year overall survival was 100% and 85%, respectively. The 3-year local control was 91% for stage II and 67% for stage III. Acute and late toxicities were acceptable without severe events. Conclusion: Weekly cisplatin and volumetric-modulated arc therapy–simultaneous integrated boost for radical treatment of advanced cervical cancer in the current cohort of elderly patients were feasible. Long-term results and prospective randomized trials are advocated. PMID:27402633
NASA Astrophysics Data System (ADS)
Barbosa, A.; Robertson, W. H.
2013-12-01
In the 2012, the National Research Council (NRC) of the National Academies' reported that one of the major issues associated with the development of climate change curriculum was the lack of interdisciplinary materials that also promoted a correlation between science standards and content. Therefore, in order to respond to this need, our group has developed an interdisciplinary climate change curriculum that has had as its fundamental basis the alignment with the guidelines presented by the Next Generation Science Standards (NGSS) and the ones presented by the international document entitled The Earth Charter. In this regards, while the alignment with NGSS disciplinary core ideas, cross-concepts and students' expectations intended to fulfill the need for the development of climate change curriculum activities that were directly associated with the appropriate set of NGSS guidelines, the alignment with The Earth Charter document intended to reinforce the need the for the integration of sociological, philosophical and intercultural analysis of the theme 'climate change'. Additionally, our curriculum was also developed as part of a collaborative project between climate scientists and engineers, who are responsible for the development of a Regional Arctic Simulation Model (RASM). Hence, another important curriculum constituent was the feedback, suggestions and reviews provided by these professionals, who have also contributed to these pedagogical materials' scientific accuracy by facilitating the integration of datasets and visualizations developed by RASM. Furthermore, our group has developed a climate change curriculum for two types of audience: high school and early undergraduate students. Each curriculum unit is divided into modules and each module contains a set of lesson plans. The topics selected to compose each unit and module were designated according to the surveys conducted with scientists and engineers involved with the development of the climate change simulation model. Inside each module, we have provided a description of the general topic being addressed, the appropriate grade levels, students' required prior knowledge, the correspondent NGSS topics, disciplinary core ideas and students' performance expectations, purpose of the activities, and lesson plan activities. Each lesson plan activity is composed by the following: an introductory text that aims at explaining the topic, activities description (classroom tasks and optional classroom activities), time frame, materials, assessment, additional readings and online resources (scientific journals, online simulation models, and books). Each module presents activities and discussions that incorporate historical, philosophical, sociological and/or scientific perspectives on the topics being addressed. Moreover, the activities and lesson plans designed to compose our curriculum have the potential of being used either individually or together, according to the teacher and topic of interest, at the same time that each unit can also be used as a full semester course.
Automatic fixation facility for plant seedlings in the TEXUS Sounding Rocket Programme.
Tewinkel, M; Burfeindt, J; Rank, P; Volkmann, D
1991-10-01
Automatic chemical fixation of plant seedlings within a 6 min period of reduced gravity (10(-4)g) was performed on three ballistic rocket flights provided by the German Sounding Rocket Programme TEXUS (Technologische Experimente unter Schwerelosigkeit = Technological Experiments in Microgravity). The described TEXUS experiment module consists of a standard experiment housing with batteries, cooling and heating systems, timer, and a data recording unit. Typically, 60 min before launch an experiment plug-in unit containing chambers with the plant material, the fixation system, and the temperature sensors is installed into the module which is already integrated in the payload section of the sounding rocket (late access). During the ballistic flight plant chambers are rapidly filled at pre-selected instants to preserve the cell structure of gravity sensing cells. After landing the plant material is processed for transmission electron microscopy. Up to now three experiments were successfully performed with cress roots (Lepidium sativum L.). Detailed improvements resulted in an automatic fixation facility which in principle can be used in unmanned missions.
Temgoua, D D Estelle; Tchokonte, M B Tchoula; Kofane, T C
2018-04-01
The generalized nonparaxial nonlinear Schrödinger (NLS) equation in optical fibers filled with chiral materials is reduced to the higher-order integrable Hirota equation. Based on the modified Darboux transformation method, the nonparaxial chiral optical rogue waves are constructed from the scalar model with modulated coefficients. We show that the parameters of nonparaxiality, third-order dispersion, and differential gain or loss term are the main keys to control the amplitude, linear, and nonlinear effects in the model. Moreover, the influence of nonparaxiality, optical activity, and walk-off effect are also evidenced under the defocusing and focusing regimes of the vector nonparaxial NLS equations with constant and modulated coefficients. Through an algorithm scheme of wider applicability on nonparaxial beam propagation methods, the most influential effect and the simultaneous controllability of combined effects are underlined, showing their properties and their potential applications in optical fibers and in a variety of complex dynamical systems.
NASA Astrophysics Data System (ADS)
Temgoua, D. D. Estelle; Tchokonte, M. B. Tchoula; Kofane, T. C.
2018-04-01
The generalized nonparaxial nonlinear Schrödinger (NLS) equation in optical fibers filled with chiral materials is reduced to the higher-order integrable Hirota equation. Based on the modified Darboux transformation method, the nonparaxial chiral optical rogue waves are constructed from the scalar model with modulated coefficients. We show that the parameters of nonparaxiality, third-order dispersion, and differential gain or loss term are the main keys to control the amplitude, linear, and nonlinear effects in the model. Moreover, the influence of nonparaxiality, optical activity, and walk-off effect are also evidenced under the defocusing and focusing regimes of the vector nonparaxial NLS equations with constant and modulated coefficients. Through an algorithm scheme of wider applicability on nonparaxial beam propagation methods, the most influential effect and the simultaneous controllability of combined effects are underlined, showing their properties and their potential applications in optical fibers and in a variety of complex dynamical systems.
Engaging Undergraduates in Soil Sustainability Decision-Making through an InTeGrate Module
ERIC Educational Resources Information Center
Fortner, Sarah K.; Scherer, Hannah H.; Murphy, Martha A.
2016-01-01
Continued agricultural productivity hinges on understanding how to manage soil resources. A 2-week undergraduate introductory-level module: "A Growing Concern: Sustaining Soil Resources Through Local Decision Making" was collaboratively developed through the InTeGrate Project. InTeGrate modules and courses engage students in grand…
Digital Image Correlation Engine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turner, Dan; Crozier, Paul; Reu, Phil
DICe is an open source digital image correlation (DIC) tool intended for use as a module in an external application or as a standalone analysis code. It's primary capability is computing full-field displacements and strains from sequences of digital These images are typically of a material sample undergoing a materials characterization experiment, but DICe is also useful for other applications (for example, trajectory tracking). DICe is machine portable (Windows, Linux and Mac) and can be effectively deployed on a high performance computing platform. Capabilities from DICe can be invoked through a library interface, via source code integration of DICe classesmore » or through a graphical user interface.« less
Development of simplified process for environmentally resistant cells
NASA Technical Reports Server (NTRS)
King, W. J.
1980-01-01
This report describes a program to develop a simple, foolproof, all vacuum solar cell manufacturing process which can be completely automated and which results in medium efficiency cells which are inherently environmentally resistant. All components of the completed cells are integrated into a monolithic structure with no material interfaces. The exposed materials (SI, Al2O3, Al, Ni) are all resistant to atmospheric attack and the junction, per se, is passivated to prevent long term degradation. Such cells are intended to be incorporated into a simple module consisting basically of a press formed metallic superstructure with a separated glass cover for missile, etc., protection.
Thermal stress response of General Purpose Heat Source (GPHS) aeroshell material
NASA Technical Reports Server (NTRS)
Grinberg, I. M.; Hulbert, L. E.; Luce, R. G.
1980-01-01
A thermal stress test was conducted to determine the ability of the GPHS aeroshell 3 D FWPF material to maintain physical integrity when exposed to a severe heat flux such as would occur from prompt reentry of GPHS modules. The test was performed in the Giant Planetary Facility at NASA's Ames Research Center. Good agreement was obtained between the theoretical and experimental results for both temperature and strain time histories. No physical damage was observed in the test specimen. These results provide initial corroboration both of the analysis techniques and that the GPHS reentry member will survive the reentry thermal stress levels expected.
Welch, James D.
2000-01-01
Disclosed are semiconductor systems, such as integrated circuits utilizing Schotky barrier and/or diffused junction technology, which semiconductor systems incorporate material(s) that form rectifying junctions in both metallurgically and/or field induced N and P-type doping regions, and methods of their use. Disclosed are Schottky barrier based inverting and non-inverting gate voltage channel induced semiconductor single devices with operating characteristics similar to multiple device CMOS systems and which can be operated as modulators, N and P-channel MOSFETS and CMOS formed therefrom, and (MOS) gate voltage controlled rectification direction and gate voltage controlled switching devices, and use of such material(s) to block parasitic current flow pathways. Simple demonstrative five mask fabrication procedures for inverting and non-inverting gate voltage channel induced semiconductor single devices with operating characteristics similar to multiple device CMOS systems are also presented.
Incident Waste Decision Support Tool - Waste Materials ...
Report This is the technical documentation to the waste materials estimator module of I-WASTE. This document outlines the methodology and data used to develop the Waste Materials Estimator (WME) contained in the Incident Waste Decision Support Tool (I-WASTE DST). Specifically, this document reflects version 6.4 of the I-WASTE DST. The WME is one of four primary features of the I-WASTE DST. The WME is both a standalone calculator that generates waste estimates in terms of broad waste categories, and is also integrated into the Incident Planning and Response section of the tool where default inventories of specific waste items are provided in addition to the estimates for the broader waste categories. The WME can generate waste estimates for both common materials found in open spaces (soil, vegetation, concrete, and asphalt) and for a vast array of items and materials found in common structures.
Integration of a Communicating Science Module into an Advanced Chemistry Laboratory Course
ERIC Educational Resources Information Center
Renaud, Jessica; Squier, Christopher; Larsen, Sarah C.
2006-01-01
A communicating science module was introduced into an advanced undergraduate physical chemistry laboratory course. The module was integrated into the course such that students received formal instruction in communicating science interwoven with the chemistry laboratory curriculum. The content of the communicating science module included three…
GaAs photovoltaics and optoelectronics using releasable multilayer epitaxial assemblies.
Yoon, Jongseung; Jo, Sungjin; Chun, Ik Su; Jung, Inhwa; Kim, Hoon-Sik; Meitl, Matthew; Menard, Etienne; Li, Xiuling; Coleman, James J; Paik, Ungyu; Rogers, John A
2010-05-20
Compound semiconductors like gallium arsenide (GaAs) provide advantages over silicon for many applications, owing to their direct bandgaps and high electron mobilities. Examples range from efficient photovoltaic devices to radio-frequency electronics and most forms of optoelectronics. However, growing large, high quality wafers of these materials, and intimately integrating them on silicon or amorphous substrates (such as glass or plastic) is expensive, which restricts their use. Here we describe materials and fabrication concepts that address many of these challenges, through the use of films of GaAs or AlGaAs grown in thick, multilayer epitaxial assemblies, then separated from each other and distributed on foreign substrates by printing. This method yields large quantities of high quality semiconductor material capable of device integration in large area formats, in a manner that also allows the wafer to be reused for additional growths. We demonstrate some capabilities of this approach with three different applications: GaAs-based metal semiconductor field effect transistors and logic gates on plates of glass, near-infrared imaging devices on wafers of silicon, and photovoltaic modules on sheets of plastic. These results illustrate the implementation of compound semiconductors such as GaAs in applications whose cost structures, formats, area coverages or modes of use are incompatible with conventional growth or integration strategies.
Monolithically Integrated Flexible Black Phosphorus Complementary Inverter Circuits.
Liu, Yuanda; Ang, Kah-Wee
2017-07-25
Two-dimensional (2D) inverters are a fundamental building block for flexible logic circuits which have previously been realized by heterogeneously wiring transistors with two discrete channel materials. Here, we demonstrate a monolithically integrated complementary inverter made using a homogeneous black phosphorus (BP) nanosheet on flexible substrates. The digital logic inverter circuit is demonstrated via effective threshold voltage tuning within a single BP material, which offers both electron and hole dominated conducting channels with nearly symmetric pinch-off and current saturation. Controllable electron concentration is achieved by accurately modulating the aluminum (Al) donor doping, which realizes BP n-FET with a room-temperature on/off ratio >10 3 . Simultaneously, work function engineering is employed to obtain a low Schottky barrier contact electrode that facilities hole injection, thus enhancing the current density of the BP p-FET by 9.4 times. The flexible inverter circuit shows a clear digital logic voltage inversion operation along with a larger-than-unity direct current voltage gain, while exhibits alternating current dynamic signal switching at a record high frequency up to 100 kHz and remarkable electrical stability upon mechanical bending with a radii as small as 4 mm. Our study demonstrates a practical monolithic integration strategy for achieving functional logic circuits on one material platform, paving the way for future high-density flexible electronic applications.
NASA Technical Reports Server (NTRS)
Leslie, Thomas M.
1993-01-01
A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film-forming material in a working device is a complex, multifaceted endeavor. It requires close attention to maintaining the optical properties of the electro-optic active portion of the polymer while manipulating the polymer structure to obtain the desired secondary polymer properties.
Semiconductor Devices and Applications. Electronics Module 5. Instructor's Guide.
ERIC Educational Resources Information Center
Chappell, John; And Others
This module is the fifth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module, a parts/equipment list, and a cross-reference table of instructional materials. Sixteen instructional units cover: semiconductor materials; diodes; diode applications and…
Nanocomposites for high-speed optical modulators and plasmonic thermal mid-infrared emitters
NASA Astrophysics Data System (ADS)
Demir, Veysi
Demand for high-speed optical modulators and narrow-bandwidth infrared thermal emitters for numerous applications continues to rise and new optical devices are needed to deal with massive data flows, processing powers, and fabrication costs. Conventional techniques are usually hindered by material limitations or electronic interconnects and advances in organic nanocomposite materials and their integration into photonic integrated circuits (PICs) have been acknowledged as a promising alternative to single crystal techniques. The work presented in this thesis uses plasmonic and magneto-optic effects towards the development of novel optical devices for harnessing light and generating high bandwidth signals (>40GHz) at room and cryogenic temperatures (4.2°K). Several publications have resulted from these efforts and are listed at the end of the abstract. In our first published research we developed a narrow-bandwidth mid-infrared thermal emitter using an Ag/dielectric/Ag thin film structure arranged in hexagonal planar lattice structures. PECVD produced nanoamorphous carbon (NAC) is used as a dielectric layer. Spectrally tunable (>2 mum) and narrow bandwidth (<0.5 mum) emission peaks in the range of 4-7 mum were demonstrated by decreasing the resistivity of NAC from 1012 and 109 O.cm with an MoSi2 dopant and increasing the emitter lattice constant from 4 to 7 mum. This technique offers excellent flexibility for developing cost-effective mid-IR sources as compared to costly fiber and quantum cascade lasers (QCLs). Next, the effect of temperature on the Verdet constant for cobalt-ferrite polymer nanocomposites was measured for a series of temperatures ranging from 40 to 200°K with a Faraday rotation polarimeter. No visual change was observed in the films during thermal cycling, and ˜4x improvement was achieved at 40°K. The results are promising and further analysis is merited at 4.2°K to assess the performance of this material for cryogenic magneto-optic modulators for supercomputers. Finally, the dielectric constant and loss tangent of MAPTMS sol-gel films were measured over a wide range of microwave frequencies. The test structures were prepared by spin-coating sol-gel films onto metallized glass substrates. The dielectric properties of the sol-gel were probed with several different sets of coplanar waveguides (CPWs) electroplated onto sol-gel films. The dielectric constant and loss-tangent of these films were determined to be ˜3.1 and 3 x 10-3 at 35GHz. These results are very promising indicating that sol-gels are viable cladding materials for high-speed electro-optic polymer modulators (>40GHz).
2009-09-01
Year Defense Plan (FYDP), on which the Department of Defense operates, subsequently needs 26 Richard G. Lugar, U.S. Senator for Indiana , “U.S...mature thin-film technologies exist such as Amorphous Silicon (a-Si), Cadmium Telluride (CdTe), and Copper Indium Gallium (di) Selenide (CIGS), all...cheaper processing, lower material costs, and is free of the environmental and health hazard issues of cadmium . Amorphous silicon coupled with
Research studies on advanced optical module/head designs for optical devices
NASA Technical Reports Server (NTRS)
Burke, James J.
1991-01-01
A summary is presented of research in optical data storage materials and of research at the center. The first section contains summary reports under the general headings of: (1) Magnetooptic media: modeling, design, fabrication, characterization, and testing; (2) Optical heads: holographic optical elements; and (3) Optical heads: integrated optics. The second section consist of a proposal entitled, Signal Processing Techniques for Optical Data Storage. And section three presents various publications prepared by the center.
2013-06-24
ISS036-E-019760 (24 June 2013) --- In the International Space Station’s Destiny laboratory, NASA astronaut Karen Nyberg, Expedition 36 flight engineer, conducts a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Philipp, Hugh T.; Tate, Mark W.; Purohit, Prafull
A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8–12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10–100 ps) and intense X-ray pulses atmore » megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. Lastly, we detail the characteristics, operation, testing and application of the detector.« less
Automated Composites Processing Technology: Film Module
NASA Technical Reports Server (NTRS)
Hulcher, A. Bruce
2004-01-01
NASA's Marshall Space Flight Center (MSFC) has developed a technology that combines a film/adhesive laydown module with fiber placement technology to enable the processing of composite prepreg tow/tape and films, foils or adhesives on the same placement machine. The development of this technology grew out of NASA's need for lightweight, permeation-resistant cryogenic propellant tanks. Autoclave processing of high performance composites results in thermally-induced stresses due to differences in the coefficients of thermal expansion of the fiber and matrix resin components. These stresses, together with the reduction in temperature due to cryogen storage, tend to initiate microcracking within the composite tank wall. One way in which to mitigate this problem is to introduce a thin, crack-resistant polymer film or foil into the tank wall. Investigation into methods to automate the processing of thin film or foil materials into composites led to the development of this technology. The concept employs an automated film supply and feed module that may be designed to fit existing fiber placement machines, or may be designed as integral equipment to new machines. This patent-pending technology can be designed such that both film and foil materials may be processed simultaneously, leading to a decrease in part build cycle time. The module may be designed having a compaction device independent of the host machine, or may utilize the host machine's compactor. The film module functions are controlled by a dedicated system independent of the fiber placement machine controls. The film, foil, or adhesive is processed via pre-existing placement machine run programs, further reducing operational expense.
NASA Astrophysics Data System (ADS)
Zolotov, Evgenii M.; Pelekhatyĭ, V. M.; Tavlykaev, R. F.
1990-05-01
A simultaneous increase in the frequency bandwidth and a reduction in the control (drive) power of integrated optical traveling-wave modulators can be achieved as a result of the electrooptic interaction in accordance with a linear frequency-modulated oscillatory law derived by inverse Fourier transformation of a rectangular amplitude-frequency characteristic and a quadratic phase-frequency characteristic of a modulator. This oscillatory law is realized using planar electrode structures with triangular or trapezoidal toothed edges. The tooth repetition frequency is governed by the linearly frequency-modulated oscillations and it rises on increase in the light modulation frequency.
Vertical electro-absorption modulator design and its integration in a VCSEL
NASA Astrophysics Data System (ADS)
Marigo-Lombart, L.; Calvez, S.; Arnoult, A.; Thienpont, H.; Almuneau, G.; Panajotov, K.
2018-04-01
Electro-absorption modulators, either embedded in CMOS technology or integrated with a semiconductor laser, are of high interest for many applications such as optical communications, signal processing and 3D imaging. Recently, the integration of a surface-normal electro-absorption modulator into a vertical-cavity surface-emitting laser has been considered. In this paper we implement a simple quantum well electro-absorption model and design and optimize an asymmetric Fabry-Pérot semiconductor modulator while considering all physical properties within figures of merit. We also extend this model to account for the impact of temperature on the different parameters involved in the calculation of the absorption, such as refractive indices and exciton transition broadening. Two types of vertical modulator structures have been fabricated and experimentally characterized by reflectivity and photocurrent measurements demonstrating a very good agreement with our model. Finally, preliminary results of an electro-absorption modulator vertically integrated with a vertical-cavity surface-emitting laser device are presented, showing good modulation performances required for high speed communications.
Deason, Vance A.; Telschow, Kenneth L.
2006-10-17
An imaging system includes: an object wavefront source and an optical microscope objective all positioned to direct an object wavefront onto an area of a vibrating subject surface encompassed by a field of view of the microscope objective, and to direct a modulated object wavefront reflected from the encompassed surface area through a photorefractive material; and a reference wavefront source and at least one phase modulator all positioned to direct a reference wavefront through the phase modulator and to direct a modulated reference wavefront from the phase modulator through the photorefractive material to interfere with the modulated object wavefront. The photorefractive material has a composition and a position such that interference of the modulated object wavefront and modulated reference wavefront occurs within the photorefractive material, providing a full-field, real-time image signal of the encompassed surface area.
Integrative modules for efficient genome engineering in yeast
Amen, Triana; Kaganovich, Daniel
2017-01-01
We present a set of vectors containing integrative modules for efficient genome integration into the commonly used selection marker loci of the yeast Saccharomyces cerevisiae. A fragment for genome integration is generated via PCR with a unique set of short primers and integrated into HIS3, URA3, ADE2, and TRP1 loci. The desired level of expression can be achieved by using constitutive (TEF1p, GPD1p), inducible (CUP1p, GAL1/10p), and daughter-specific (DSE4p) promoters available in the modules. The reduced size of the integrative module compared to conventional integrative plasmids allows efficient integration of multiple fragments. We demonstrate the efficiency of this tool by simultaneously tagging markers of the nucleus, vacuole, actin, and peroxisomes with genomically integrated fluorophores. Improved integration of our new pDK plasmid series allows stable introduction of several genes and can be used for multi-color imaging. New bidirectional promoters (TEF1p-GPD1p, TEF1p-CUP1p, and TEF1p-DSE4p) allow tractable metabolic engineering. PMID:28660202
Laser-controlled optical transconductance varistor system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nguyen, Hoang T.; Stuart, Brent C.
2017-07-11
An optical transconductance varistor system having a modulated radiation source configured to provide modulated stimulus, a wavelength converter operably connected to the modulated radiation source to produce a modulated stimulus having a predetermined wavelength, and a wide bandgap semiconductor photoconductive material in contact between two electrodes. The photoconductive material is operably coupled, such as by a beam transport module, to receive the modulated stimulus having the predetermined wavelength to control a current flowing through the photoconductive material when a voltage potential is present across the electrodes.
Zhang, Ning; Ma, Yansong; Weir, Michael D.; Xu, Hockin H. K.; Bai, Yuxing; Melo, Mary Anne S.
2017-01-01
Dental polymeric composites have become the first choice for cavity restorations due to their esthetics and capacity to be bonded to the tooth. However, the oral cavity is considered to be harsh environment for a polymeric material. Oral biofilms can degrade the polymeric components, thus compromising the marginal integrity and leading to the recurrence of caries. Recurrent caries around restorations has been reported as the main reason for restoration failure. The degradation of materials greatly compromises the clinical longevity. This review focuses on the degradation process of resin composites by oral biofilms, the mechanisms of degradation and its consequences. In addition, potential future developments in the area of resin-based dental biomaterials with an emphasis on anti-biofilm strategies are also reviewed. PMID:28772863
Guo, Peijun; Schaller, Richard D.; Ocola, Leonidas E.; ...
2016-08-15
Active control of light is important for photonic integrated circuits, optical switches,. and telecommunications. Coupling light with acoustic vibrations in nanoscale optical resonators offers optical modulation capabilities with high bandwidth and Small footprint Instead of using noble metals, here we introduce indium tin-oxide nanorod arrays (ITO-NRAs) as the operating media;and demonstrate optical modulation covering the visible spectral range (from 360 to 700 nm), with similar to 20 GHz bandwidth through the excitation of coherent acoustic vibrations in ITO-NRAs. This broadband modulation results from the collective optical diffraction by the dielectric ITO-NRAs, and a high differential transmission modulation up to 10%more » is achieved through efficient near-infrared, on-plasmon-resonance pumping. By combining the frequency signatures Of the vibrational modes with finite-element simulations, we,further determine the anisotropic elastic constants for single-crystalline ITO, which are not known-for the bulk phase. Furthermore, this technique to determine elastic constants using Coherent acoustic vibrations of uniform nanostructures can be generalized to the study of other inorganic materials.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Peijun; Schaller, Richard D.; Ocola, Leonidas E.
Active control of light is important for photonic integrated circuits, optical switches,. and telecommunications. Coupling light with acoustic vibrations in nanoscale optical resonators offers optical modulation capabilities with high bandwidth and Small footprint Instead of using noble metals, here we introduce indium tin-oxide nanorod arrays (ITO-NRAs) as the operating media;and demonstrate optical modulation covering the visible spectral range (from 360 to 700 nm), with similar to 20 GHz bandwidth through the excitation of coherent acoustic vibrations in ITO-NRAs. This broadband modulation results from the collective optical diffraction by the dielectric ITO-NRAs, and a high differential transmission modulation up to 10%more » is achieved through efficient near-infrared, on-plasmon-resonance pumping. By combining the frequency signatures Of the vibrational modes with finite-element simulations, we,further determine the anisotropic elastic constants for single-crystalline ITO, which are not known-for the bulk phase. Furthermore, this technique to determine elastic constants using Coherent acoustic vibrations of uniform nanostructures can be generalized to the study of other inorganic materials.« less
Zhang, Jing; De Groote, Andreas; Abbasi, Amin; Loi, Ruggero; O'Callaghan, James; Corbett, Brian; Trindade, António José; Bower, Christopher A; Roelkens, Gunther
2017-06-26
A 4-channel silicon photonics transceiver array for Point-to-Point (P2P) fiber-to-the-home (FTTH) optical networks at the central office (CO) side is demonstrated. A III-V O-band photodetector array was integrated onto the silicon photonic transmitter through transfer printing technology, showing a polarization-independent responsivity of 0.39 - 0.49 A/W in the O-band. The integrated PDs (30 × 40 μm 2 mesa) have a 3 dB bandwidth of 11.5 GHz at -3 V bias. Together with high-speed C-band silicon ring modulators whose bandwidth is up to 15 GHz, operation of the transceiver array at 10 Gbit/s is demonstrated. The use of transfer printing for the integration of the III-V photodetectors allows for an efficient use of III-V material and enables the scalable integration of III-V devices on silicon photonics wafers, thereby reducing their cost.
Polymer enabled 100 Gbaud connectivity for datacom applications
NASA Astrophysics Data System (ADS)
Katopodis, V.; Groumas, P.; Zhang, Z.; Dinu, R.; Miller, E.; Konczykowska, A.; Dupuy, J.-Y.; Beretta, A.; Dede, A.; Choi, J. H.; Harati, P.; Jorge, F.; Nodjiadjim, V.; Riet, Muriel; Cangini, G.; Vannucci, A.; Keil, N.; Bach, H.-G.; Grote, N.; Avramopoulos, H.; Kouloumentas, Ch.
2016-03-01
Polymers hold the promise for ultra-fast modulation of optical signals due to their potential for ultra-fast electro-optic (EO) response and high EO coefficient. In this work, we present the basic structure and properties of an efficient EO material system, and we summarize the efforts made within the project ICT-POLYSYS for the development of high-speed transmitters based on this system. More specifically, we describe successful efforts for the monolithic integration of multi-mode interference (MMI) couplers and Bragg-gratings (BGs) along with Mach-Zehnder modulators (MZMs) on this platform, and for the hybrid integration of InP active elements in the form of laser diodes (LDs) and gain chips (GCs). Using these integration techniques and the combination of the hybrid optical chips with ultra-fast indium phosphide double heterojunction bipolar transistor (InP-DHBT) electronics, we develop and fully package a single 100 Gb/s transmitter and a 2×100 Gb/s transmitter that can support serial operation at this rate with conventional non-return-to-zero on-off-keying (NRZ-OOK) modulation format. We also present the experimental evaluation of the devices, validating the efficiency of the monolithic and hybrid integration concepts and confirming the potential of this technology for single-lane 100 Gb/s optical connectivity in data-center network environments. Results from transmission experiments to this end include the achievement of BER close to 6·10-9 in B2B configuration, the achievement of BER lower than 10-7 for propagation over standard single-mode fiber (SSMF) with total length up to 1000 m, and the achievement of BER at the level of 10-5 after 1625 m of SSMF. Finally, plans for the use of the EO polymer system in a more complex hybrid integration platform for high-flexibility/high-capacity transmitters are also outlined.
NASA Astrophysics Data System (ADS)
Orr, C. H.; McFadden, R.; Manduca, C. A.; Newman, A.
2016-12-01
Teaching sustainability curriculum provides an opportunity for building connections between academic learning and examples, experiences, and issues from beyond academia. Done well, this can increase students interest in a topic that feels relevant to their lives and help them transfer this learning to real life situations in their professional and personal lives. To support this approach to teaching, the NSF STEP Center InTeGrate developed a set of five core principles to guide development of teaching materials and programs that draw content from grand challenges to society and work to improve students' ability to understand the nature of science and think like a scientist. These principles include both effective pedagogical approaches and an interdisciplinary framework and are reflected in example curriculum modules, and implementation programs supported by InTeGrate. In order to promote adoption of teaching aligned with the InTeGrate philosophy and to use the InTeGrate-developed materials as tools, we organized a public webinar series led by materials developers and program leaders in the InTeGrate community. The webinars highlight programs that have addressed bigger-scale challenges such as increasing diversity of our majors and creating pathways to the workforce, as well as the materials used by these programs. They provide detailed examples designed to help other groups implement similar programs including showcase teaching activities and examples of their use in a wide range of settings. The webinars are interactive, with built-in activities and reflections that promote discussion among participants and speakers. Topics include natural hazards and risks, water resources and sustainability, energy and atmosphere, integrating sustainability into your course, and tracing environmental contaminants. These have clear components of geoscience, but promote an interdisciplinary perspective, that provides a deeper and more thorough discussion. Each webinar is archived on the InTeGrate website. We invite people to learn about InTeGrate teaching strategies, activities, and interdisciplinary approaches, and models for implementing the principles highlighted through the STEP Center work.
NASA Astrophysics Data System (ADS)
Bosch, Henry
2016-03-01
A heat exchanger concept for a thermoelectric generator with integrated planar modules for passenger car applications is introduced. The module housings, made of deep drawn stainless steel sheet metal, are brazed onto the exhaust gas channel to achieve an optimal heat transfer on the hot side of the modules. The cooling side consists of winding fluid channels, which are mounted directly onto the cold side of the modules. Only a thin foil separates the cooling media from the modules for an almost direct heat contact on the cooling side. Thermoelectric generators with up to 20 modules made of PbTe and Bi2Te3, respectively, are manufactured and tested on a hot gas generator to investigate electrical power output and performance of the thermoelectric generator. The proof of concept of the light weight heat exchanger design made of sheet metal with integrated modules is positively accomplished.
NASA Astrophysics Data System (ADS)
Huang, Bo
Enzyme-catalyzed degradation of the restoration-tooth interface compromises interfacial integrity, thereby contributing to secondary caries, which is a major cause of resin-based restoration failure. It is hypothesized that in addition to salivary esterases, the cariogenic bacterium Streptococcus mutans has specific esterases that degrade the resin-dentin interface, releasing biodegradation by- products (BBPs) such as bis-hydroxy-propoxy-phenyl-propane (BisHPPP). In turn, BisHPPP affects S. mutans by stimulating the expression of esterases. Another hypothesis is that the biostability of the resin-dentin interface is affected by simulated salivary esterases, dentinal matrix metalloproteinase (MMP) inhibition, and restorative materials. To test the first hypothesis, putative esterase genes in S. mutans UA159 were identified, purified, and characterized. SMU_118c was identified as the dominant esterase in S. mutans UA159 and showed a similar hydrolytic activity profile to salivary esterases. BisHPPP upregulated expression of the SMU_118c gene and related protein in a concentration-dependent manner. This positive feedback process could accelerate the degradation of the restoration-tooth interface and lead to premature restoration failure. To test the second hypothesis, an in vitro model was established to evaluate the effects of salivary esterases, MMP inhibition and restorative materials on interfacial integrity. It was confirmed that interfacial integrity was compromised with time and was further deteriorated by simulated salivary esterases, as indicated by the greater depth of bacterial ingress and more bacterial biomass of biofilm along the interface. However, this process could be modulated by using different restorative materials and MMPs inhibition. This project elucidated the mechanistic interaction between oral bacteria and restorative materials and established a new, in vitro, and physiologically relevant model to assess the effect of material chemistry, properties, and application modes on bacterial penetration and biofilm formation. These findings offer the oral health community practical ways to reduce secondary caries by altering material composition and restorative procedures.
Health, migration and border management: analysis and capacity-building at Europe's borders.
Hollings, Jennifer; Samuilova, Mariya; Petrova-Benedict, Roumyana
2012-04-01
Three key elements were analysed in Hungary, Poland and Slovakia as a basis for strengthening the capacity of staff and structures related to health, migration and border management: public health concerns linked to migration, health needs and rights of migrants and the occupational health of staff. This IOM project was implemented through an in-depth situation analysis as well as the development of training modules and public health guidelines. Findings indicate a paucity of existing data, gaps in the health care for migrants and few existing tools for border officials and health professionals. Sets of training modules were developed for each of these groups, including common modules on migration and the right to health and intercultural communication, as well as targeted health modules. The guidelines promote good practices in the context of border management and detention. The EU is working towards a common immigration policy and integrated border management; however, a harmonized approach to migration and health is still lacking. Further research and piloting of the developed materials is needed to fully establish an adaptable, common toolkit.
Packaging of ferroelectric liquid crystal-on-silicon spatial light modulators
NASA Astrophysics Data System (ADS)
Lin, W.; Morozova, Nina D.; Ju, TehHua; Zhang, Weidong; Lee, Yung-Cheng; McKnight, Douglas J.; Johnson, Kristina M.
1996-11-01
A self-pulling soldering technology has been demonstrated for assembling liquid crystal on silicon (LCOS) spatial light modulators (SLMs). One of the major challenges in manufacturing the LCOS modules is to reproducibly control the thickness of the gap between the very large scale integrated circuit (VLSI) chip and the cover glass. The liquid crystal material is sandwiched between the VLSI chop and the cover glass which is coated with a transparent conductor. Solder joints with different profiles and sizes have been designed to provide surface tension forces to control the gap accommodating the ferroelectric liquid crystal layer in the range of a micron level with sub- micron uniformity. The optimum solder joint design is defined as a joint that results in the maximum pulling force. This technology provides an automatic, batch assembly process for a LCOS SLM through one reflow process. Fluxless soldering technology is used to assemble the module. This approach avoids residues from chemical of flux and oxides, and eliminates potential contamination to the device. Two different LCOS SLM designs and the process optimization are described.
Ultra high frequency imaging acoustic microscope
Deason, Vance A.; Telschow, Kenneth L.
2006-05-23
An imaging system includes: an object wavefront source and an optical microscope objective all positioned to direct an object wavefront onto an area of a vibrating subject surface encompassed by a field of view of the microscope objective, and to direct a modulated object wavefront reflected from the encompassed surface area through a photorefractive material; and a reference wavefront source and at least one phase modulator all positioned to direct a reference wavefront through the phase modulator and to direct a modulated reference wavefront from the phase modulator through the photorefractive material to interfere with the modulated object wavefront. The photorefractive material has a composition and a position such that interference of the modulated object wavefront and modulated reference wavefront occurs within the photorefractive material, providing a full-field, real-time image signal of the encompassed surface area.
Coordination in Large Scale Software Development
1990-01-01
toward achieving common and explicitly recognized goals" (Blau and Scott, 1962) and "the integration or linking together of different parts of an...require a strong degree of integration of its components. Much software is built of thousands of modules that must mesh with each other perfectly for the...coordination between subgroups producing software modules could lead to failure in integrating the modules themselves. Informal communication. Both
Mathematical Methods of System Analysis in Construction Materials
NASA Astrophysics Data System (ADS)
Garkina, Irina; Danilov, Alexander
2017-10-01
System attributes of construction materials are defined: complexity of an object, integrity of set of elements, existence of essential, stable relations between elements defining integrative properties of system, existence of structure, etc. On the basis of cognitive modelling (intensive and extensive properties; the operating parameters) materials (as difficult systems) and creation of the cognitive map the hierarchical modular structure of criteria of quality is under construction. It actually is a basis for preparation of the specification on development of material (the required organization and properties). Proceeding from a modern paradigm (model of statement of problems and their decisions) of development of materials, levels and modules are specified in structure of material. It when using the principles of the system analysis allows to considered technological process as the difficult system consisting of elements of the distinguished specification level: from atomic before separate process. Each element of system depending on an effective objective is considered as separate system with more detailed levels of decomposition. Among them, semantic and qualitative analyses of an object (are considered a research objective, decomposition levels, separate elements and communications between them come to light). Further formalization of the available knowledge in the form of mathematical models (structural identification) is carried out; communications between input and output parameters (parametrical identification) are defined. Hierarchical structures of criteria of quality are under construction for each allocated level. On her the relevant hierarchical structures of system (material) are under construction. Regularities of structurization and formation of properties, generally are considered at the levels from micro to a macrostructure. The mathematical model of material is represented as set of the models corresponding to private criteria by which separate modules and their levels (the mathematical description, a decision algorithm) are defined. Adequacy is established (compliance of results of modelling to experimental data; is defined by the level of knowledge of process and validity of the accepted assumptions). The global criterion of quality of material is considered as a set of private criteria (properties). Synthesis of material is carried out on the basis of one-criteria optimization on each of the chosen private criteria. Results of one-criteria optimization are used at multicriteria optimization. The methods of developing materials as single-purpose, multi-purpose, including contradictory, systems are indicated. The scheme of synthesis of composite materials as difficult systems is developed. The specified system approach effectively was used in case of synthesis of composite materials with special properties.
Time encoded radiation imaging
Marleau, Peter; Brubaker, Erik; Kiff, Scott
2014-10-21
The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.
Materials-Process Interactions in Ternary Alloy Semiconductors.
1984-08-01
high, the surface potential can be * modulated . PECVD SiO. appears to be a viable candidate as a gate dielectric for * Irf ,fO-4A)s MISFETs...it is desirable to integrate the detectors with circuits capable of performing signal processing functions. These circuits can either be fabricated in...to be a major problem in In0. 5 3Ga 0.* 47 s. 25 S. . . . . 13821 -1 R I (a) CROSS SECTION KEYBOARD 210M ANNEALING CHAMBER GATE TRIGG TRIAC
High resolution projection micro stereolithography system and method
Spadaccini, Christopher M.; Farquar, George; Weisgraber, Todd; Gemberling, Steven; Fang, Nicholas; Xu, Jun; Alonso, Matthew; Lee, Howon
2016-11-15
A high-resolution P.mu.SL system and method incorporating one or more of the following features with a standard P.mu.SL system using a SLM projected digital image to form components in a stereolithographic bath: a far-field superlens for producing sub-diffraction-limited features, multiple spatial light modulators (SLM) to generate spatially-controlled three-dimensional interference holograms with nanoscale features, and the integration of microfluidic components into the resin bath of a P.mu.SL system to fabricate microstructures of different materials.
2017-03-17
The payload fairing containing the Orbital ATK Cygnus pressurized cargo module is lowered onto the Centaur upper stage, or second stage, of the United Launch Alliance (ULA) rocket in the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
2017-03-17
The payload fairing containing the Orbital ATK Cygnus pressurized cargo module is mated to the Centaur upper stage, or second stage, of the United Launch Alliance (ULA) rocket in the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
2013-06-24
ISS036-E-019830 (24 June 2013) --- In the International Space Station’s Destiny laboratory, NASA astronaut Karen Nyberg, Expedition 36 flight engineer, speaks into a microphone while conducting a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.
3D packaging of a microfluidic system with sensory applications
NASA Astrophysics Data System (ADS)
Morrissey, Anthony; Kelly, Gerard; Alderman, John C.
1997-09-01
Among the main benefits of microsystem technology are its contributions to cost reductio, reliability and improved performance. however, the packaging of microsystems, and particularly microsensor, has proven to be one of the biggest limitations to their commercialization and the packaging of silicon sensor devices can be the most costly part of their fabrication. This paper describes the integration of 3D packaging of a microsystem. Central to the operation of the 3D demonstrator is a micromachined silicon membrane pump to supply fluids to a sensing chamber constructed about the active area of a sensor chip. This chip carries ISFET based chemical sensors, pressure sensors and thermal sensors. The electronics required for controlling and regulating the activity of the various sensors ar also available on this chip and as other chips in the 3D assembly. The demonstrator also contains a power supply module with optical fiber interconnections. All of these modules are integrated into a single plastic- encapsulated 3D vertical multichip module. The reliability of such a structure, initially proposed by Val was demonstrated by Barrett et al. An additional module available for inclusion in some of our assemblies is a test chip capable of measuring the packaging-induced stress experienced during and after assembly. The packaging process described produces a module with very high density and utilizes standard off-the-shelf components to minimize costs. As the sensor chip and micropump include micromachined silicon membranes and microvalves, the packaging of such structures has to allow consideration for the minimization of the packaging-induced stresses. With this in mind, low stress techniques, including the use of soft glob-top materials, were employed.
Photovoltaic module encapsulation design and materials selection, volume 1
NASA Technical Reports Server (NTRS)
Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.
1982-01-01
Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.
AEROELASTIC SIMULATION TOOL FOR INFLATABLE BALLUTE AEROCAPTURE
NASA Technical Reports Server (NTRS)
Liever, P. A.; Sheta, E. F.; Habchi, S. D.
2006-01-01
A multidisciplinary analysis tool is under development for predicting the impact of aeroelastic effects on the functionality of inflatable ballute aeroassist vehicles in both the continuum and rarefied flow regimes. High-fidelity modules for continuum and rarefied aerodynamics, structural dynamics, heat transfer, and computational grid deformation are coupled in an integrated multi-physics, multi-disciplinary computing environment. This flexible and extensible approach allows the integration of state-of-the-art, stand-alone NASA and industry leading continuum and rarefied flow solvers and structural analysis codes into a computing environment in which the modules can run concurrently with synchronized data transfer. Coupled fluid-structure continuum flow demonstrations were conducted on a clamped ballute configuration. The feasibility of implementing a DSMC flow solver in the simulation framework was demonstrated, and loosely coupled rarefied flow aeroelastic demonstrations were performed. A NASA and industry technology survey identified CFD, DSMC and structural analysis codes capable of modeling non-linear shape and material response of thin-film inflated aeroshells. The simulation technology will find direct and immediate applications with NASA and industry in ongoing aerocapture technology development programs.
Arefin, Md Shamsul; Redoute, Jean-Michel; Yuce, Mehmet Rasit
2018-01-01
This paper presents a wireless capsule microsystem to detect and monitor the pH, pressure, and temperature of the gastrointestinal tract in real time. This research contributes to the integration of sensors (microfabricated capacitive pH, capacitive pressure, and resistive temperature sensors), frequency modulation and pulse width modulation based interface IC circuits, microcontroller, and transceiver with meandered conformal antenna for the development of a capsule system. The challenges associated with the system miniaturization, higher sensitivity and resolution of sensors, and lower power consumption of interface circuits are addressed. The layout, PCB design, and packaging of a miniaturized wireless capsule, having diameter of 13 mm and length of 28 mm, have successfully been implemented. A data receiver and recorder system is also designed to receive physiological data from the wireless capsule and to send it to a computer for real-time display and recording. Experiments are performed in vitro using a stomach model and minced pork as tissue simulating material. The real-time measurements also validate the suitability of sensors, interface circuits, and meandered antenna for wireless capsule applications.
Sheikhaleh, Arash; Abedi, Kambiz; Jafari, Kian; Gholamzadeh, Reza
2016-11-10
In this paper, we propose what we believe is a novel sensitive micro-optoelectromechanical systems (MOEMS) accelerometer based on intensity modulation by using a one-dimensional photonic crystal. The optical sensing system of the proposed structure includes an air-dielectric multilayer photonic bandgap material, a laser diode (LD) light source, a typical photodiode (1550 nm) and a set of integrated optical waveguides. The proposed sensor provides several advantages, such as a relatively wide measurement range, good linearity in the whole measurement range, integration capability, negligible cross-axis sensitivity, high reliability, and low air-damping coefficient, which results in a wider frequency bandwidth for a fixed resonance frequency. Simulation results show that the functional characteristics of the sensor are as follows: a mechanical sensitivity of 119.21 nm/g, a linear measurement range of ±38g and a resonance frequency of 1444 Hz. Thanks to the above-mentioned characteristics, the proposed MOEMS accelerometer is suitable for a wide spectrum of applications, ranging from consumer electronics to aerospace and inertial navigation.
NASA Astrophysics Data System (ADS)
Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Matsumoto, Atsushi; Kawanishi, Tetsuya
2016-04-01
A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed with T-band (1.0 µm waveband) and O-band (1.3 µm waveband) QD optical gain materials for Gbps-order, high-speed optical data generation. The insertion loss due to coupling between the device and the optical fiber was effectively compensated for by the SOA section. It was also confirmed that the monolithic QD-OGM/SOA device enabled >4.8 Gbps optical data generation with a clear eye opening in the T-band. Furthermore, we successfully demonstrated error-free 4.8 Gbps optical data transmissions in each of the six wavelength channels over a 10-km-long photonic crystal fiber using the monolithic QD-OGM/SOA device in multiple O-band wavelength channels, which were generated by the single QD gain chip. These results suggest that the monolithic QD-OGM/SOA device will be advantageous in ultra-broadband optical frequency systems that utilize the T+O-band for short- and medium-range optical communications.
Application of electrically invisible antennas to the modulated scatterer technique
NASA Astrophysics Data System (ADS)
Crocker, Dylan Andrew
The Modulated Scatterer Technique (MST) has shown promise for applications in microwave imaging, electric field mapping, and materials characterization. Traditionally, MST scatterers consist of dipole antennas centrally loaded with a lumped element capable of modulation (commonly a PIN diode). By modulating the load element, the signal scattered from the MST scatterer is also modulated. However, due to the small size of such scatterers, it can be difficult to reliably detect the modulated signal. Increasing the modulation depth (a parameter related to how well the scatterer modulates the scattered signal) may improve the detectability of the scattered signal. In an effort to improve the modulation depth of scatterers commonly used in MST, the concept of electrically invisible antennas is applied to the design of these scatterers and is the focus of this work. Electrical invisibility of linear antennas, such as loaded dipoles, can be achieved by loading a scatterer in such a way that, when illuminated by an electromagnetic wave, the integral of the current induced along the length of the scatterer (and hence the scattered field as well) approaches zero. By designing a scatterer to be capable of modulation between visible (scattering) and invisible (minimum scattering) states, the modulation depth may be improved. This thesis presents simulations and measurements of new MST scatterers that have been designed to be electrically invisible during the reverse bias state of the modulated element (i.e., a PIN diode). Further, the scattering during the forward bias state remains the same as that of a traditional MST scatterer, resulting in an increase in modulation depth. This new MST scatterer design technique may also have application in improving the performance of similar sensors such as radio frequency identification (RFID) tags.
Safe Handling and Use of Flammable and Combustible Materials. Module SH-30. Safety and Health.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
This student module on safe handling and use of flammable and combustible materials is one of 50 modules concerned with job safety and health. This module introduces the student to the hazards of flammable and combustible materials and the measures necessary to control those hazards. Following the introduction, 14 objectives (each keyed to a page…
Sutherland, J. C.
2016-07-20
Photoelastic modulators can alter the polarization state of a beam of ultraviolet, visible or infrared photons by means of periodic stress-induced differences in the refractive index of a transparent material that forms the optical element of the device and is isotropic in the absence of stress. Furthermore, they have found widespread application in instruments that characterize or alter the polarization state of a beam in fields as diverse as astronomy, structural biology, materials science and ultraviolet lithography for the manufacture of nano-scale integrated circuits. Measurement of circular dichroism, the differential absorption of left- and right circularly polarized light, and ofmore » strain-induced birefringence of optical components are major applications. Instruments using synchrotron radiation and photoelastic modulators with CaF 2 optical elements have extended circular dichroism measurements down to wavelengths of about 130 nm in the vacuum ultraviolet. Maintaining a constant phase shift between two orthogonal polarization states across a spectrum requires that the amplitude of the modulated stress be changed as a function of wavelength. For commercially available photoelastic modulators, the voltage that controls the amplitude of modulation required to produce a specified phase shift, which is a surrogate for the stress modulation amplitude, has been shown to be an approximately linear function of wavelength in the spectral region where the optical element is transparent. But, extrapolations of such straight lines cross zero voltage at a non-zero wavelength, not at zero-wavelength. For modulators with calcium fluoride and fused silica optical elements, the zero-crossing wavelength is always in the spectral region where the optical element of the modulator strongly absorbs the incident radiation, and at a wavelength less than the longest-wavelength apparent resonance deduced from experimental values of the refractive index fit to the Sellmeier equation. Using a model that relates the refractive indices of a stressed optical element to the refractive index of its unstressed state, an expression for the modulator control voltage was derived that closely fits the experimental data. Our result provides a theoretical rational for the apparently linear constant-phase programming voltage, and thus provides theoretical backing for the calibration procedure frequently used for these modulators. Lastly there are other factors that can influence the calibration of a photoelastic modulator, including temperature and atmospheric pressure, are discussed briefly.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sutherland, J. C.
Photoelastic modulators can alter the polarization state of a beam of ultraviolet, visible or infrared photons by means of periodic stress-induced differences in the refractive index of a transparent material that forms the optical element of the device and is isotropic in the absence of stress. Furthermore, they have found widespread application in instruments that characterize or alter the polarization state of a beam in fields as diverse as astronomy, structural biology, materials science and ultraviolet lithography for the manufacture of nano-scale integrated circuits. Measurement of circular dichroism, the differential absorption of left- and right circularly polarized light, and ofmore » strain-induced birefringence of optical components are major applications. Instruments using synchrotron radiation and photoelastic modulators with CaF 2 optical elements have extended circular dichroism measurements down to wavelengths of about 130 nm in the vacuum ultraviolet. Maintaining a constant phase shift between two orthogonal polarization states across a spectrum requires that the amplitude of the modulated stress be changed as a function of wavelength. For commercially available photoelastic modulators, the voltage that controls the amplitude of modulation required to produce a specified phase shift, which is a surrogate for the stress modulation amplitude, has been shown to be an approximately linear function of wavelength in the spectral region where the optical element is transparent. But, extrapolations of such straight lines cross zero voltage at a non-zero wavelength, not at zero-wavelength. For modulators with calcium fluoride and fused silica optical elements, the zero-crossing wavelength is always in the spectral region where the optical element of the modulator strongly absorbs the incident radiation, and at a wavelength less than the longest-wavelength apparent resonance deduced from experimental values of the refractive index fit to the Sellmeier equation. Using a model that relates the refractive indices of a stressed optical element to the refractive index of its unstressed state, an expression for the modulator control voltage was derived that closely fits the experimental data. Our result provides a theoretical rational for the apparently linear constant-phase programming voltage, and thus provides theoretical backing for the calibration procedure frequently used for these modulators. Lastly there are other factors that can influence the calibration of a photoelastic modulator, including temperature and atmospheric pressure, are discussed briefly.« less
ERIC Educational Resources Information Center
McPherson, Kenard; Weidman, James R.
This volume contains materials to supplement existing driver education programming offered by high schools to youthful (16- to 18-year old) drivers. Section I contains three drinking/driving modules: an information-only module, a self-image module, and a three-unit peer intervention module. An instructor's guide provided for each module includes…
Active Metamaterials for Terahertz Communication and Imaging
NASA Astrophysics Data System (ADS)
Rout, Saroj
In recent years there has been significant interest in terahertz (THz) systems mostly due to their unique applications in communication and imaging. One of the primary reason for this resurgence is the use of metamaterials to design THz devices due to lack of natural materials that can respond to this electromagnetic spectrum, the so-called ''THz gap''. Even after years of intense research, THz systems are complex and expensive, unsuitable for mainstream applications. This work focuses on bridging this gap by building all solid-state THz devices for imaging and communication applications in a commercial integrated circuit (IC) technology. One such canonical device is a THz wave modulator that can be used in THz wireless communication devices and as spatial light modulator (SLM) for THz imaging systems. The key contribution of this thesis is a metamaterial based THz wave modulator fabricated in a commercial gallium arsenide (GaAs) process resonant at 0.46 THz using a novel approach of embedding pseudomorphic high electron mobility transistors (pHEMTs) in metamaterial and demonstrate modulation values over 30%, and THz modulation at frequencies up to 10 MHz. Using the THz wave modulator, we fabricated and experimentally demonstrated an all solid-state metamaterial based THz spatial light modulator (SLM) as a 2x2 pixel array operating around 0.46 THz, by raster scanning an occluded metal object in polystyrene using a single-pixel imaging setup. This was an important step towards building an low-voltage (1V), low power, on-chip integrable THz imaging device. Using the characterization result from the THz SLM, we computationally demonstrated a multi-level amplitude shift keying (ASK) terahertz wireless communication system using spatial light modulation instead of traditional voltage mode modulation, achieving higher spectral efficiency for high speed communication. We show two orders of magnitude improvement in symbol error rate (SER) for a degradation of 20 dB in transmit signal-to-noise ratio (SNR). We have computationally demonstrated a novel pictorial modulation technique showing N/log2(N) improvement in bandwidth using a N-tile SLM compared to standard spatial modulation using a single-pixel detector. Finally, we demonstrate a path to realize a terahertz focal plane array (FPA) using a commercial 0.18 mum CMOS foundry process. Through EM simulation and circuit simulation we have demonstrated a metamaterial based THz detectors at 230-325 GHz that can be used in a focal plane array.
Novel Techniques for Millimeter-Wave Packages
NASA Technical Reports Server (NTRS)
Herman, Martin I.; Lee, Karen A.; Kolawa, Elzbieta A.; Lowry, Lynn E.; Tulintseff, Ann N.
1995-01-01
A new millimeter-wave package architecture with supporting electrical, mechanical and material science experiment and analysis is presented. This package is well suited for discrete devices, monolithic microwave integrated circuits (MMIC's) and multichip module (MCM) applications. It has low-loss wide-band RF transitions which are necessary to overcome manufacturing tolerances leading to lower per unit cost Potential applications of this new packaging architecture which go beyond the standard requirements of device protection include integration of antennas, compatibility to photonic networks and direct transitions to waveguide systems. Techniques for electromagnetic analysis, thermal control and hermetic sealing were explored. Three dimensional electromagnetic analysis was performed using a finite difference time-domain (FDTD) algorithm and experimentally verified for millimeter-wave package input and output transitions. New multi-material system concepts (AlN, Cu, and diamond thin films) which allow excellent surface finishes to be achieved with enhanced thermal management have been investigated. A new approach utilizing block copolymer coatings was employed to hermetically seal packages which met MIL STD-883.
An Integrated Teaching Module.
ERIC Educational Resources Information Center
Samuel, Marie R.; Seiferth, Berniece B.
This integrated teaching module provides elementary and junior high school teachers with a "hands-on" approach to studying the Anasazi Indian. Emphasis is on creative exploration that focuses on integrating art, music, poetry, writing, geography, dance, history, anthropology, sociology, and archaeology. Replicas of artifacts,…
Senna, Irene; Maravita, Angelo; Bolognini, Nadia; Parise, Cesare V.
2014-01-01
Our body is made of flesh and bones. We know it, and in our daily lives all the senses constantly provide converging information about this simple, factual truth. But is this always the case? Here we report a surprising bodily illusion demonstrating that humans rapidly update their assumptions about the material qualities of their body, based on their recent multisensory perceptual experience. To induce a misperception of the material properties of the hand, we repeatedly gently hit participants' hand with a small hammer, while progressively replacing the natural sound of the hammer against the skin with the sound of a hammer hitting a piece of marble. After five minutes, the hand started feeling stiffer, heavier, harder, less sensitive, unnatural, and showed enhanced Galvanic skin response (GSR) to threatening stimuli. Notably, such a change in skin conductivity positively correlated with changes in perceived hand stiffness. Conversely, when hammer hits and impact sounds were temporally uncorrelated, participants did not spontaneously report any changes in the perceived properties of the hand, nor did they show any modulation in GSR. In two further experiments, we ruled out that mere audio-tactile synchrony is the causal factor triggering the illusion, further demonstrating the key role of material information conveyed by impact sounds in modulating the perceived material properties of the hand. This novel bodily illusion, the ‘Marble-Hand Illusion', demonstrates that the perceived material of our body, surely the most stable attribute of our bodily self, can be quickly updated through multisensory integration. PMID:24621793
Wide-band analog frequency modulation of optic signals using indirect techniques
NASA Technical Reports Server (NTRS)
Fitzmartin, D. J.; Balboni, E. J.; Gels, R. G.
1991-01-01
The wideband frequency modulation (FM) of an optical carrier by a radio frequency (RF) or microwave signal can be accomplished independent of laser type when indirect modulation is employed. Indirect modulators exploit the integral relation of phase to frequency so that phase modulators can be used to impress frequency modulation on an optical carrier. The use of integrated optics phase modulators, which are highly linear, enables the generation of optical wideband FM signals with very low intermodulation distortion. This modulator can be used as part of an optical wideband FM link for RF and microwave signals. Experimental results from the test of an indirect frequency modulator for an optical carrier are discussed.
Development and testing of advanced fire-resistant photovoltaic modules
NASA Technical Reports Server (NTRS)
Sugimura, R. S.; Otth, D. H.; Ross, R. G., Jr.
1985-01-01
The evaluation of back-surface materials flammability in order to identify fire resistant module designs is examined. The fire test apparatus, burning-brand test sequence, and spread-of-flame test sequence are described. Video recordings and time-temperature profiles of module back surfaces are utilized to study the flammability failure mechanism and identify high-temperature materials. A table of flammability test results for various module designs is provided. The data reveals that 2-mil kapton, fiberglass cloth coated or impregnated with a material to plug pores, and metal foil back-surface materials achieve class A and B fire-resistance levels, and are applicable for photovoltaic module designs.
Fundamental concepts of integrated and fiber optic sensors
NASA Technical Reports Server (NTRS)
Tuma, Margaret L.
1995-01-01
This chapter discusses fiber optic and integrated optic sensor concepts. Unfortunately, there is no standard method to categorize these sensor concepts. Here, fiber optic and integrated optic sensor concepts will be categorized by the primary modulation technique. These modulation techniques have been classified as: intensity, phase, wavelength, polarization, and time/frequency modulation. All modulate the output light with respect to changes in the physical or chemical property to be measured. Each primary modulation technique is then divided into fiber optic and integrated optic sections which are treated independently. For each sensor concept, possible sensor applications are discussed. The sensors and references discussed are not exhaustive, but sufficient to give the reader an overview of sensor concepts developed to date. Sensor multiplexing techniques such as wavelength division, time division, and frequency division will not be discussed as they are beyond the scope of this report.
Thermal Expansion of Vitrified Blood Vessels Permeated with DP6 and Synthetic Ice Modulators
Eisenberg, David P.; Taylor, Michael J.; Jimenez-Rios, Jorge L.; Rabin, Yoed
2014-01-01
This study provides thermal expansion data for blood vessels permeated with the cryoprotective cocktail DP6, when combined with selected synthetic ice modulators (SIMs): 12% polyethylene glycol 400, 6% 1,3-cyclohexanediol, and 6% 2,3-butanediol. The general classification of SIMs includes molecules that modulate ice nucleation and growth, or possess properties of stabilizing the amorphous state, by virtue of their chemical structure and at concentrations that are not explained on a purely colligative basis. The current study is part of an ongoing effort to characterize thermo-mechanical effects on structural integrity of cryopreserved materials, where thermal expansion is the driving mechanism to thermo-mechanical stress. This study focuses on the lower part of the cryogenic temperature range, where the cryoprotective agent (CPA) behaves as a solid for all practical applications. By combining results obtained in the current study with literature data on the thermal expansion in the upper part of the cryogenic temperature range, unified thermal expansion curves are presented. PMID:24769313
ERIC Educational Resources Information Center
Navarro Coll., Corsicana, TX.
This module is the first in a series of eleven modules in an energy conservation curriculum for secondary and postsecondary vocational students. It is designed for use by itself, to be integrated with the other ten modules into a program on energy conservation, or to be integrated into conventional vocational courses as a unit of instruction. The…
Combined, solid-state molecular property and gamma spectrometers for CBRNE detection
NASA Astrophysics Data System (ADS)
Rogers, Ben; Grate, Jay; Pearson, Brett; Gallagher, Neal; Wise, Barry; Whitten, Ralph; Adams, Jesse
2013-05-01
Nevada Nanotech Systems, Inc. (Nevada Nano) has developed a multi-sensor solution to Chemical, Biological, Radiological, Nuclear and Explosives (CBRNE) detection that combines the Molecular Property Spectrometer™ (MPS™)—a micro-electro-mechanical chip-based technology capable of measuring a variety of thermodynamic and electrostatic molecular properties of sampled vapors and particles—and a compact, high-resolution, solid-state gamma spectrometer module for identifying radioactive materials, including isotopes used in dirty bombs and nuclear weapons. By conducting multiple measurements, the system can provide a more complete characterization of an unknown sample, leading to a more accurate identification. Positive identifications of threats are communicated using an integrated wireless module. Currently, system development is focused on detection of commercial, military and improvised explosives, radioactive materials, and chemical threats. The system can be configured for a variety of CBRNE applications, including handheld wands and swab-type threat detectors requiring short sample times, and ultra-high sensitivity detectors in which longer sampling times are used. Here we provide an overview of the system design and operation and present results from preliminary testing.
Xu, Renxiao; Lee, Jung Woo; Pan, Taisong; Ma, Siyi; Wang, Jiayi; Han, June Hyun; Ma, Yinji; Rogers, John A; Huang, Yonggang
2017-01-26
Many recently developed soft, skin-like electronics with high performance circuits and low modulus encapsulation materials can accommodate large bending, stretching, and twisting deformations. Their compliant mechanics also allows for intimate, nonintrusive integration to the curvilinear surfaces of soft biological tissues. By introducing a stacked circuit construct, the functional density of these systems can be greatly improved, yet their desirable mechanics may be compromised due to the increased overall thickness. To address this issue, the results presented here establish design guidelines for optimizing the deformable properties of stretchable electronics with stacked circuit layers. The effects of three contributing factors (i.e., the silicone inter-layer, the composite encapsulation, and the deformable interconnects) on the stretchability of a multilayer system are explored in detail via combined experimental observation, finite element modeling, and theoretical analysis. Finally, an electronic module with optimized design is demonstrated. This highly deformable system can be repetitively folded, twisted, or stretched without observable influences to its electrical functionality. The ultrasoft, thin nature of the module makes it suitable for conformal biointegration.
Xu, Renxiao; Lee, Jung Woo; Pan, Taisong; Ma, Siyi; Wang, Jiayi; Han, June Hyun; Ma, Yinji
2017-01-01
Many recently developed soft, skin-like electronics with high performance circuits and low modulus encapsulation materials can accommodate large bending, stretching, and twisting deformations. Their compliant mechanics also allows for intimate, nonintrusive integration to the curvilinear surfaces of soft biological tissues. By introducing a stacked circuit construct, the functional density of these systems can be greatly improved, yet their desirable mechanics may be compromised due to the increased overall thickness. To address this issue, the results presented here establish design guidelines for optimizing the deformable properties of stretchable electronics with stacked circuit layers. The effects of three contributing factors (i.e., the silicone inter-layer, the composite encapsulation, and the deformable interconnects) on the stretchability of a multilayer system are explored in detail via combined experimental observation, finite element modeling, and theoretical analysis. Finally, an electronic module with optimized design is demonstrated. This highly deformable system can be repetitively folded, twisted, or stretched without observable influences to its electrical functionality. The ultrasoft, thin nature of the module makes it suitable for conformal biointegration. PMID:29046624
Damage Detection and Self-Repair in Inflatable/Deployable Structures
NASA Technical Reports Server (NTRS)
Brandon, Erik; Studor, George; Banks, DAvid; Curry, Mark; Broccato, Robert; Jackson, Tom; Champaigne, Kevin; Sottos, Nancy
2009-01-01
Inflatable/deployable structures are under consideration for applications as varied as expansion modules for the International Space Station to destinations for space tourism to habitats for the lunar surface. Monitoring and maintaining the integrity of the physical structure is critical, particularly since these structures rely on non-traditional engineering materials such as fabrics, foams, and elastomeric polymers to provide the primary protection for the human crew. The closely related prior concept of monitoring structural integrity by use of built-in or permanently attached sensors has been applied to structures made of such standard engineering materials as metals, alloys, and rigid composites. To effect monitoring of flexible structures comprised mainly of soft goods, however, it will be necessary to solve a different set of problems - especially those of integrating power and data-transfer cabling that can withstand, and not unduly interfere with, stowage and subsequent deployment of the structures. By incorporating capabilities for self-repair along with capabilities for structural health monitoring, successful implementation of these technologies would be a significant step toward semi-autonomous structures, which need little human intervention to maintain. This would not only increase the safety of these structures, but also reduce the inspection and maintenance costs associated with more conventional structures.
Engineering and fabrication cost considerations for cryogenic wind tunnel models
NASA Technical Reports Server (NTRS)
Boykin, R. M., Jr.; Davenport, J. B., Jr.
1983-01-01
Design and fabrication cost drivers for cryogenic transonic wind tunnel models are defined. The major cost factors for wind tunnel models are model complexity, tolerances, surface finishes, materials, material validation, and model inspection. The cryogenic temperatures require the use of materials with relatively high fracture toughness but at the same time high strength. Some of these materials are very difficult to machine, requiring extensive machine hours which can add significantly to the manufacturing costs. Some additional engineering costs are incurred to certify the materials through mechanical tests and nondestructive evaluation techniques, which are not normally required with conventional models. When instrumentation such as accelerometers and electronically scanned pressure modules is required, temperature control of these devices needs to be incorporated into the design, which requires added effort. Additional thermal analyses and subsystem tests may be necessary, which also adds to the design costs. The largest driver to the design costs is potentially the additional static and dynamic analyses required to insure structural integrity of the model and support system.
Analogy-Integrated e-Learning Module: Facilitating Students' Conceptual Understanding
ERIC Educational Resources Information Center
Florida, Jennifer
2012-01-01
The study deals with the development of an analogy-integrated e-learning module on Cellular Respiration, which is intended to facilitate conceptual understanding of students with different brain hemisphere dominance and learning styles. The module includes eight analogies originally conceptualized following the specific steps used to prepare…
This proposal pertains to the on-going development of the Data Collection Manager (DCM) module, which is one of three modules that compose MIRA, Multi-criteria Integrated Resource Assessment. MIRA is Region III's newly conceived and continually developing decision support approac...
High extinction ratio integrated optical modulator for quantum telecommunication systems
NASA Astrophysics Data System (ADS)
Tronev, A.; Parfenov, M.; Agruzov, P.; Ilichev, I.; Shamray, A.
2018-01-01
A method for increasing the extinction ratio of integrated optical Mach-Zehnder modulators based on LiNbO3 via the photorefractive effect is proposed. The influence of the photorefractive effect on the X- and Y-splitters of intensity modulators is experimentally studied. An increase in the modulator extinction ratio by 17 dB (from 30 to 47 dB) is obtained. It is shown that fabricated modulators with a high extinction ratio are important for quantum key distribution systems.
NASA Astrophysics Data System (ADS)
Brook, A.; Cristofani, E.; Vandewal, M.; Matheis, C.; Jonuscheit, J.; Beigang, R.
2012-05-01
The present study proposes a fully integrated, semi-automatic and near real-time mode-operated image processing methodology developed for Frequency-Modulated Continuous-Wave (FMCW) THz images with the center frequencies around: 100 GHz and 300 GHz. The quality control of aeronautics composite multi-layered materials and structures using Non-Destructive Testing is the main focus of this work. Image processing is applied on the 3-D images to extract useful information. The data is processed by extracting areas of interest. The detected areas are subjected to image analysis for more particular investigation managed by a spatial model. Finally, the post-processing stage examines and evaluates the spatial accuracy of the extracted information.
Conceptual Trade Study of General Purpose Heat Source Powered Stirling Converter Configurations
NASA Technical Reports Server (NTRS)
Turpin, J. B.
2007-01-01
This Technical Manual describes a parametric study of general purpose heat source (GPHS) powered Stirling converter configurations. This study was performed in support of MSFC s efforts to establish the capability to perform non-nuclear system level testing and integration of radioisotope power systems. Six different GPHS stack configurations at a total of three different power levels (80, 250, and 500 W(sub e) were analyzed. The thermal profiles of the integrated GPHS modules (for each configuration) were calculated to determine maximum temperatures for comparison to allowable material limits. Temperature profiles for off-nominal power conditions were also assessed in order to better understand how power demands from the Stirling engine impact the performance of a given configuration.
Transverse-longitudinal integrated resonator
Hutchinson, Donald P [Knoxville, TN; Simpson, Marcus L [Knoxville, TN; Simpson, John T [Knoxville, TN
2003-03-11
A transverse-longitudinal integrated optical resonator (TLIR) is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide. The PBG is positioned between the first and second subwavelength resonant gratings. An electro-optic waveguide material may be used to permit tuning the TLIR and to permit the TLIR to perform signal modulation and switching. The TLIR may be positioned on a bulk substrate die with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a TLIR including fabricating a broadband reflective grating is disclosed. A method for tuning the TLIR's transmission resonance wavelength is also disclosed.
Upgrading and extended testing of the MSC integrated water and waste management hardware
NASA Technical Reports Server (NTRS)
Bambenek, R. A.; Nuccio, P. P.; Hurley, T. L.; Jasionowski, W. J.
1972-01-01
The results are presented of upgrading and testing an integrated water and waste management system, which uses the compression distillation, reverse osmosis, adsorption filtration and ion-exchange processes to recover potable water from urine, flush water and used wash water. Also included is the development of techniques for extending the useful biological life of biological filters, activated carbon filters and ion-exchange resins to at least 30 days, and presterilizing ion-exchange resins so that sterile water can be recovered from waste water. A wide variety of reverse osmosos materials, surfactants and germicides were experimentally evaluated to determine the best combination for a wash water subsystem. Full-scale module tests with real wash water demonstrated that surface fouling is a major problem.
Flexible Proton-Gated Oxide Synaptic Transistors on Si Membrane.
Zhu, Li Qiang; Wan, Chang Jin; Gao, Ping Qi; Liu, Yang Hui; Xiao, Hui; Ye, Ji Chun; Wan, Qing
2016-08-24
Ion-conducting materials have received considerable attention for their applications in fuel cells, electrochemical devices, and sensors. Here, flexible indium zinc oxide (InZnO) synaptic transistors with multiple presynaptic inputs gated by proton-conducting phosphorosilicate glass-based electrolyte films are fabricated on ultrathin Si membranes. Transient characteristics of the proton gated InZnO synaptic transistors are investigated, indicating stable proton-gating behaviors. Short-term synaptic plasticities are mimicked on the proposed proton-gated synaptic transistors. Furthermore, synaptic integration regulations are mimicked on the proposed synaptic transistor networks. Spiking logic modulations are realized based on the transition between superlinear and sublinear synaptic integration. The multigates coupled flexible proton-gated oxide synaptic transistors may be interesting for neuroinspired platforms with sophisticated spatiotemporal information processing.
Advanced 3-V semiconductor technology assessment
NASA Technical Reports Server (NTRS)
Nowogrodzki, M.
1983-01-01
Components required for extensions of currently planned space communications systems are discussed for large antennas, crosslink systems, single sideband systems, Aerostat systems, and digital signal processing. Systems using advanced modulation concepts and new concepts in communications satellites are included. The current status and trends in materials technology are examined with emphasis on bulk growth of semi-insulating GaAs and InP, epitaxial growth, and ion implantation. Microwave solid state discrete active devices, multigigabit rate GaAs digital integrated circuits, microwave integrated circuits, and the exploratory development of GaInAs devices, heterojunction devices, and quasi-ballistic devices is considered. Competing technologies such as RF power generation, filter structures, and microwave circuit fabrication are discussed. The fundamental limits of semiconductor devices and problems in implementation are explored.
2D Materials for Optical Modulation: Challenges and Opportunities.
Yu, Shaoliang; Wu, Xiaoqin; Wang, Yipei; Guo, Xin; Tong, Limin
2017-04-01
Owing to their atomic layer thickness, strong light-material interaction, high nonlinearity, broadband optical response, fast relaxation, controllable optoelectronic properties, and high compatibility with other photonic structures, 2D materials, including graphene, transition metal dichalcogenides and black phosphorus, have been attracting increasing attention for photonic applications. By tuning the carrier density via electrical or optical means that modifies their physical properties (e.g., Fermi level or nonlinear absorption), optical response of the 2D materials can be instantly changed, making them versatile nanostructures for optical modulation. Here, up-to-date 2D material-based optical modulation in three categories is reviewed: free-space, fiber-based, and on-chip configurations. By analysing cons and pros of different modulation approaches from material and mechanism aspects, the challenges faced by using these materials for device applications are presented. In addition, thermal effects (e.g., laser induced damage) in 2D materials, which are critical to practical applications, are also discussed. Finally, the outlook for future opportunities of these 2D materials for optical modulation is given. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
White Paper: Radiological Curriculum for Undergraduate Medical Education in Germany.
Ertl-Wagner, B; Barkhausen, J; Mahnken, A H; Mentzel, H J; Uder, M; Weidemann, J; Stumpp, P
2016-11-01
Purpose: Radiology represents a highly relevant part of undergraduate medical education from preclinical studies to subinternship training. It is therefore important to establish a content base for teaching radiology in German Medical Faculties. Materials and Methods: The German Society of Radiology (DRG) developed a model curriculum for radiological teaching at German medical universities, which is presented in this article. There is also a European model curriculum for undergraduate teaching (U-level curriculum of the European Society of Radiology). In a modular concept, the students shall learn important radiological core principles in the realms of knowledge, skills and competences as well as core scientific competences in the imaging sciences. Results: The curriculum is divided into two modules. Module 1 includes principles of radiation biology, radiation protection and imaging technology, imaging anatomy as well as the risks and side effects of radiological methods, procedures and contrast media. This module is modality-oriented. Module 2 comprises radiological diagnostic decision-making and imaging-based interventional techniques for various disease entities. This module is organ system-oriented. Conclusion: The curriculum is meant as a living document to be amended and revised at regular intervals. The curriculum can be used as a basis for individual curricular development at German Medical Faculties. It can be integrated into traditional or reformed medical teaching curricula. Key Points: • Radiology is an integral and important part of medical education.• The German Society of Radiology (DRG) developed a model curriculum for teaching radiology at German Medical Faculties to help students develop the ability to make medical decisions based on scientific knowledge and act accordingly.• This curriculum can be used for individual curricular development at medical departments. It is divided into two modules with several chapters. Citation Format: • Ertl-Wagner B, Barkhausen J, Mahnken AH et al. White Paper: Radiological Curriculum for Undergraduate Medical Education in Germany. Fortschr Röntgenstr 2016; 188: 1017 - 1023. © Georg Thieme Verlag KG Stuttgart · New York.
High-speed X-ray imaging pixel array detector for synchrotron bunch isolation
Philipp, Hugh T.; Tate, Mark W.; Purohit, Prafull; ...
2016-01-28
A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8–12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10–100 ps) and intense X-ray pulses atmore » megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. Lastly, we detail the characteristics, operation, testing and application of the detector.« less
High-speed X-ray imaging pixel array detector for synchrotron bunch isolation
Philipp, Hugh T.; Tate, Mark W.; Purohit, Prafull; Shanks, Katherine S.; Weiss, Joel T.; Gruner, Sol M.
2016-01-01
A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8–12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10–100 ps) and intense X-ray pulses at megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. The characteristics, operation, testing and application of the detector are detailed. PMID:26917125
High-speed X-ray imaging pixel array detector for synchrotron bunch isolation.
Philipp, Hugh T; Tate, Mark W; Purohit, Prafull; Shanks, Katherine S; Weiss, Joel T; Gruner, Sol M
2016-03-01
A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8-12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10-100 ps) and intense X-ray pulses at megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. The characteristics, operation, testing and application of the detector are detailed.
Materials Handling. Module SH-01. Safety and Health.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
This student module on materials handling is one of 50 modules concerned with job safety and health. It presents the procedures for safe materials handling. Discussed are manual handling methods (lifting and carrying by hand) and mechanical lifting (lifting by powered trucks, cranes or conveyors). Following the introduction, 15 objectives (each…
1987-01-16
Occupational Health Information Management System (NOHIMS) 6 Hazardous Materials Control Module (HMC) User’s Manual 7. Author(s) 8. Performing Organization...Materials Control (HMC) module of the Naval Medical Command’s (NAVMED) Navy Occupational Health Information Management System (NOHIMS). After presenting
Integrable high order UWB pulse photonic generator based on cross phase modulation in a SOA-MZI.
Moreno, Vanessa; Rius, Manuel; Mora, José; Muriel, Miguel A; Capmany, José
2013-09-23
We propose and experimentally demonstrate a potentially integrable optical scheme to generate high order UWB pulses. The technique is based on exploiting the cross phase modulation generated in an InGaAsP Mach-Zehnder interferometer containing integrated semiconductor optical amplifiers, and is also adaptable to different pulse modulation formats through an optical processing unit which allows to control of the amplitude, polarity and time delay of the generated taps.
Electro-optic voltage sensor head
Crawford, T.M.; Davidson, J.R.; Woods, G.K.
1999-08-17
The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers. 6 figs.
Electro-optic voltage sensor head
Crawford, Thomas M.; Davidson, James R.; Woods, Gregory K.
1999-01-01
The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers.
NASA Technical Reports Server (NTRS)
Tri, Terry O.; Kennedy, Kriss J.; Toups, Larry; Gill, Tracy R.; Howe, A. Scott
2011-01-01
This paper describes the construction, assembly, subsystem integration, transportation, and field testing operations associated with the Habitat Demonstration Unit (HDU) Pressurized Excursion Module (PEM) and discusses lessons learned. In a one-year period beginning summer 2009, a tightly scheduled design-develop-build process was utilized by a small NASA "tiger team" to produce the functional HDU-PEM prototype in time to participate in the 2010 Desert Research and Technology Studies (Desert RATS) field campaign. The process required the coordination of multiple teams, subcontractors, facility management and safety staff. It also required a well-choreographed material handling and transportation process to deliver the finished product from the NASA-Johnson Space Center facilities to the remote Arizona desert locations of the field test. Significant findings of this paper include the team s greater understanding of the HDU-PEM s many integration issues and the in-field training the team acquired which will enable the implementation of the next-generation of improvements and development of high-fidelity field operations in a harsh environment. The Desert RATS analog environment is being promoted by NASA as an efficient means to design, build, and integrate multiple technologies in a mission architecture context, with the eventual goal of evolving the technologies into robust flight hardware systems. The HDU-PEM in-field demonstration at Desert RATS 2010 provided a validation process for the integration team, which has already begun to retool for the 2011 field tests that require an adapted architecture.
Nonreciprocal Thermal Material by Spatiotemporal Modulation
NASA Astrophysics Data System (ADS)
Torrent, Daniel; Poncelet, Olivier; Batsale, Jean-Chirstophe
2018-03-01
The thermal properties of a material with a spatiotemporal modulation, in the form of a traveling wave, in both the thermal conductivity and the specific heat capacity are studied. It is found that these materials behave as materials with an internal convectionlike term that provides them with nonreciprocal properties, in the sense that the heat flux has different properties when it propagates in the same direction or in the opposite one to the modulation of the parameters. An effective medium description is presented which accurately describes the modulated material, and numerical simulations support this description and verify the nonreciprocal properties of the material. It is found that these materials are promising candidates for the design of thermal diodes and other advanced devices for the control of the heat flow at all scales.
ERIC Educational Resources Information Center
Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
These instructor materials for an aviation maintenance technology course contain three instructional modules covering safety, aviation mathematics, and aviation physics. Each module may contain an introduction and module objective, specific objectives, an instructor's module implementation guide, technical information supplements, transparency…
Bardella, Paolo; Chow, Weng; Montrosset, Ivo
2016-01-08
In the last decades, various solutions have been proposed to increase the modulation bandwidth and consequently the transmission bit rate of integrated semiconductor lasers. In this manuscript we discuss a design procedure for a recently proposed laser structure realized with the integration of two DBR lasers. Design guidelines will be proposed and dynamic small and large signal simulations, calculated using a Finite Difference Traveling Wave numerical simulator, will be performed to confirm the design results and the effectiveness of the analyzed integrated configuration to achieve a direct modulation bandwidth up to 80 GHz
Surface studies of solids using integral x-ray-induced photoemission yield
Stoupin, Stanislav; Zhernenkov, Mikhail; Shi, Bing
2016-11-22
X-ray induced photoemission yield contains structural information complementary to that provided by X-ray Fresnel reflectivity, which presents an advantage to a wide variety of surface studies if this information is made easily accessible. Photoemission in materials research is commonly acknowledged as a method with a probing depth limited by the escape depth of the photoelectrons. Here we show that the integral hard-X-ray-induced photoemission yield is modulated by the Fresnel reflectivity of a multilayer structure and carries structural information that extends well beyond the photoelectron escape depth. A simple electric self-detection of the integral photoemission yield and Fourier data analysis permitmore » extraction of thicknesses of individual layers. The approach does not require detection of the reflected radiation and can be considered as a framework for non-invasive evaluation of buried layers with hard X-rays under grazing incidence.« less
Surface studies of solids using integral X-ray-induced photoemission yield
Stoupin, Stanislav; Zhernenkov, Mikhail; Shi, Bing
2016-01-01
X-ray induced photoemission yield contains structural information complementary to that provided by X-ray Fresnel reflectivity, which presents an advantage to a wide variety of surface studies if this information is made easily accessible. Photoemission in materials research is commonly acknowledged as a method with a probing depth limited by the escape depth of the photoelectrons. Here we show that the integral hard-X-ray-induced photoemission yield is modulated by the Fresnel reflectivity of a multilayer structure and carries structural information that extends well beyond the photoelectron escape depth. A simple electric self-detection of the integral photoemission yield and Fourier data analysis permit extraction of thicknesses of individual layers. The approach does not require detection of the reflected radiation and can be considered as a framework for non-invasive evaluation of buried layers with hard X-rays under grazing incidence. PMID:27874041
Ground Operations Autonomous Control and Integrated Health Management
NASA Technical Reports Server (NTRS)
Daniels, James
2014-01-01
The Ground Operations Autonomous Control and Integrated Health Management plays a key role for future ground operations at NASA. The software that is integrated into this system is called G2 2011 Gensym. The purpose of this report is to describe the Ground Operations Autonomous Control and Integrated Health Management with the use of the G2 Gensym software and the G2 NASA toolkit for Integrated System Health Management (ISHM) which is a Computer Software Configuration Item (CSCI). The decision rationale for the use of the G2 platform is to develop a modular capability for ISHM and AC. Toolkit modules include knowledge bases that are generic and can be applied in any application domain module. That way, there's a maximization of reusability, maintainability, and systematic evolution, portability, and scalability. Engine modules are generic, while application modules represent the domain model of a specific application. Furthermore, the NASA toolkit, developed since 2006 (a set of modules), makes it possible to create application domain models quickly, using pre-defined objects that include sensors and components libraries for typical fluid, electrical, and mechanical systems.
Design and Construction of Manned Lunar Base
NASA Astrophysics Data System (ADS)
Li, Zhijie
2016-07-01
Building manned lunar base is one of the core aims of human lunar exploration project, which is also an important way to carry out the exploitation and utilization of lunar in situ resources. The most important part of manned lunar base is the design and construction of living habitation and many factors should be considered including science objective and site selection. Through investigating and research, the scientific goals of manned lunar base should be status and characteristics ascertainment of lunar available in situ resources, then developing necessary scientific experiments and utilization of lunar in situ resources by using special environment conditions of lunar surface. The site selection strategy of manned lunar base should rely on scientific goals according to special lunar surface environment and engineering capacity constraints, meanwhile, consulting the landing sites of foreign unmanned and manned lunar exploration, and choosing different typical regions of lunar surface and analyzing the landform and physiognomy, reachability, thermal environment, sunlight condition, micro meteoroids protection and utilization of in situ resources, after these steps, a logical lunar living habitation site should be confirmed. This paper brings out and compares three kinds of configurations with fabricating processes of manned lunar base, including rigid module, flexible and construction module manned lunar base. 1.The rigid habitation module is usually made by metal materials. The design and fabrication may consult the experience of space station, hence with mature technique. Because this configuration cannot be folded or deployed, which not only afford limit working and living room for astronauts, but also needs repetitious cargo transit between earth and moon for lunar base extending. 2. The flexible module habitation can be folded in fairing while launching. When deploying on moon, the configuration can be inflatable or mechanically-deployed, which means under the condition of the same volume it has less weight than rigid module, but based on durable, high hermetic, low density and elastic modulus advanced materials. 3.The construction habitation has high expansibility and various configurations by using in situ resources as construction materials, but this technique is difficult to implement since it involves deep exploitation of lunar resources. Aiming at different missions' objects and development periods, three different patterns talked above can be chosen as the scheme of lunar base habitation establishments. But each of them is too simple to adapt high-level lunar base during a long period. Thereby, based on the design of rigid module and flexible module, this paper brings out an assumed scheme of an integrated lunar base, and the exterior part of lunar base is built by using construction technique. The design of lunar base follows the principle of crew-robot coordinated exploration, which functions automatically in a long period and short period with attention by astronauts. The technique characteristics are as follows: life period ≥ 8 years; 6 astronauts; single lunar surface mission period ≥ 3 months. The inner main body of integrated manned lunar base consists of habitation module, laboratory module and support module. In order to afford security and comfortableness, the habitation module provides astronauts kitchen, bedroom, gymnasium, toilet, and so on. The laboratory module is used for science experiments, which involves plant cultivation devices and animal cultivation devices of bioregenerative life support system. The communication system, main computer, central control system and backup powers are arranged in the support module. For convenience of outside working and emergency rescue, every module with two exports is connected with other modules or lunar rovers. In order to solve the problems of waste treatment, atmosphere/water regeneration and food supply, this paper designed a bioregenerative life support system based on physical/chemic-regenerative life support system, which includes microbial waste treatment system, plants cultivation system and animal-protein production system. Energy is another important aspect needs to be solved when building lunar base habitation. The steps of lunar base building process are divided into lunar surface landing, transport, unloading, assembly and construction. Thus the activity systems including lunar lander, lunar chain block, various lunar rovers, robots and 3D printing machine are needed while building a lunar base. For the sake of enough power support for these facilities, the integrated manned lunar base will use solar + nuclear energy plus regenerative fuel cell together with 180kW power to satisfy the requirement of power supply. Besides these two questions talked above, the lunar base habitation also needs to solve the problem of lunar dust protection. Lunar dust grains are sharp and have electrostatic adsorption, which means this kind of dust may damage the functions of spacesuit, lunar rover and other equipments, and it may cause diseases if breathed by astronauts, consequently, lunar dust protection and cleaning mechanism needs to be founded and the anti-dust, automatic dust removal and self-cleaning materials need to be used. At last, this paper puts forward corresponding advices about building lunar base by using international collaboration. Out of question, the construction of lunar base is a huge project, it is very hard to be accomplished by any country alone since lots of uncertain complications exist there. By this token, international collaboration is a certain development direction, and lots of aerospace countries have already achieved the breakout of correlation key technologies, in order to avoid unnecessary waste, the dispersive advantageous resources need to be combined together.
High-Performance Silicon-Germanium-Based Thermoelectric Modules for Gas Exhaust Energy Scavenging
NASA Astrophysics Data System (ADS)
Romanjek, K.; Vesin, S.; Aixala, L.; Baffie, T.; Bernard-Granger, G.; Dufourcq, J.
2015-06-01
Some of the energy used in transportation and industry is lost as heat, often at high-temperatures, during conversion processes. Thermoelectricity enables direct conversion of heat into electricity, and is an alternative to the waste-heat-recovery technology currently used, for example turbines and other types of thermodynamic cycling. The performance of thermoelectric (TE) materials and modules has improved continuously in recent decades. In the high-temperature range ( T hot side > 500°C), silicon-germanium (SiGe) alloys are among the best TE materials reported in the literature. These materials are based on non-toxic elements. The Thermoelectrics Laboratory at CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives) has synthesized n and p-type SiGe pellets, manufactured TE modules, and integrated these into thermoelectric generators (TEG) which were tested on a dedicated bench with hot air as the source of heat. SiGe TE samples of diameter 60 mm were created by spark-plasma sintering. For n-type SiGe doped with phosphorus the peak thermoelectric figure of merit reached ZT = 1.0 at 700°C whereas for p-type SiGe doped with boron the peak was ZT = 0.75 at 700°C. Thus, state-of-the-art conversion efficiency was obtained while also achieving higher production throughput capacity than for competing processes. A standard deviation <4% in the electrical resistance of batches of ten pellets of both types was indicative of high reproducibility. A silver-paste-based brazing technique was used to assemble the TE elements into modules. This assembly technique afforded low and repeatable electrical contact resistance (<3 nΩ m2). A test bench was developed for measuring the performance of TE modules at high temperatures (up to 600°C), and thirty 20 mm × 20 mm TE modules were produced and tested. The results revealed the performance was reproducible, with power output reaching 1.9 ± 0.2 W for a 370 degree temperature difference. When the temperature difference was increased to 500°C, electrical power output increased to >3.6 W. An air-water heat exchanger was developed and 30 TE modules were clamped and connected electrically. The TEG was tested under vacuum on a hot-air test bench. The measured output power was 45 W for an air flow of 16 g/s at 750°C. The hot surface of the TE module reached 550°C under these conditions. Silicon-germanium TE modules can survive such temperatures, in contrast with commercial modules based on bismuth telluride, which are limited to 400°C.
NASA Technical Reports Server (NTRS)
Gaucher, Brian P. (Inventor); Grzyb, Janusz (Inventor); Liu, Duixian (Inventor); Pfeiffer, Ullrich R. (Inventor)
2008-01-01
Apparatus and methods are provided for packaging IC chips together with integrated antenna modules designed to provide a closed EM (electromagnetic) environment for antenna radiators, thereby allowing antennas to be designed independent from the packaging technology.
NASA Astrophysics Data System (ADS)
Cho, Chun-Hyung; Kim, Jongseong; Sung, Hyuk-Kee
2016-09-01
We report on the enhancement of the static extinction ratio by using a dual-section distributed feedback laser diode integrated with an electro-absorption modulator. A directly- modulated dual-section laser can provide improved modulation performance under a low bias level ( i.e., below the threshold level) compared with a standard directly-modulated laser. By combining the extinction ratio from a dual-section laser with that from an electro-absorption modulator section, a total extinction ratio of 49.6. dB are successfully achieved.
Pan, Jui-Wen; Tu, Sheng-Han
2012-05-20
A cost-effective, high-throughput, and high-yield method for the efficiency enhancement of an optical mouse lighting module is proposed. We integrated imprinting technology and free-form surface design to obtain a lighting module with high illumination efficiency and uniform intensity distribution. The imprinting technique can increase the light extraction efficiency and modulate the intensity distribution of light-emitting diodes. A modulated light source was utilized to add a compact free-form surface element to create a lighting module with 95% uniformity and 80% optical efficiency.
Waveguide-based electro-absorption modulator performance: comparative analysis
NASA Astrophysics Data System (ADS)
Amin, Rubab; Khurgin, Jacob B.; Sorger, Volker J.
2018-06-01
Electro-optic modulation is a key function for data communication. Given the vast amount of data handled, understanding the intricate physics and trade-offs of modulators on-chip allows revealing performance regimes not explored yet. Here we show a holistic performance analysis for waveguide-based electro-absorption modulators. Our approach centers around material properties revealing obtainable optical absorption leading to effective modal cross-section, and material broadening effects. Taken together both describe the modulator physical behavior entirely. We consider a plurality of material modulation classes to include two-level absorbers such as quantum dots, free carrier accumulation or depletion such as ITO or Silicon, two-dimensional electron gas in semiconductors such as quantum wells, Pauli blocking in Graphene, and excitons in two-dimensional atomic layered materials such as found in transition metal dichalcogendies. Our results show that reducing the modal area generally improves modulator performance defined by the amount of induced electrical charge, and hence the energy-per-bit function, required switching the signal. We find that broadening increases the amount of switching charge needed. While some material classes allow for reduced broadening such as quantum dots and 2-dimensional materials due to their reduced Coulomb screening leading to increased oscillator strengths, the sharpness of broadening is overshadowed by thermal effects independent of the material class. Further we find that plasmonics allows the switching charge and energy-per-bit function to be reduced by about one order of magnitude compared to bulk photonics. This analysis is aimed as a guide for the community to predict anticipated modulator performance based on both existing and emerging materials.
Integrating Oracle Human Resources with Other Modules
NASA Technical Reports Server (NTRS)
Sparks, Karl; Shope, Shawn
1998-01-01
One of the most challenging aspects of implementing an enterprise-wide business system is achieving integration of the different modules to the satisfaction of diverse customers. The Jet Propulsion Laboratory's (JPL) implementation of the Oracle application suite demonstrates the need to coordinate Oracle Human Resources Management System (HRMS) decision across the Oracle modules.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. Instructional Materials Lab.
This learner manual for rescuers covers the current techniques or practices required in the rescue service. The fifth of 10 modules contains information on hazardous materials. Key points, an introduction, and conclusion accompany substantive material in this module. In addition, the module contains a Department of Transportation guide chart on…
Modulating the level of components within plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bobzin, Steven Craig; Apuya, Nestor; Chiang, Karen
Materials and Methods for identifying lignin regulatory region-regulatory protein associations are disclosed. Materials and methods for modulating lignin accumulation are also disclosed. In addition, methods and materials for modulating (e.g., increasing or decreasing) the level of a component (e.g., protein, oil, lignin, carbon, a carotenoid, or a triterpenoid) in plants are disclosed.
Gradation (approx. 10 size states) of synaptic strength by quantal addition of structural modules
2017-01-01
Memory storage involves activity-dependent strengthening of synaptic transmission, a process termed long-term potentiation (LTP). The late phase of LTP is thought to encode long-term memory and involves structural processes that enlarge the synapse. Hence, understanding how synapse size is graded provides fundamental information about the information storage capability of synapses. Recent work using electron microscopy (EM) to quantify synapse dimensions has suggested that synapses may structurally encode as many as 26 functionally distinct states, which correspond to a series of proportionally spaced synapse sizes. Other recent evidence using super-resolution microscopy has revealed that synapses are composed of stereotyped nanoclusters of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and scaffolding proteins; furthermore, synapse size varies linearly with the number of nanoclusters. Here we have sought to develop a model of synapse structure and growth that is consistent with both the EM and super-resolution data. We argue that synapses are composed of modules consisting of matrix material and potentially one nanocluster. LTP induction can add a trans-synaptic nanocluster to a module, thereby converting a silent module to an AMPA functional module. LTP can also add modules by a linear process, thereby producing an approximately 10-fold gradation in synapse size and strength. This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’. PMID:28093559
Gradation (approx. 10 size states) of synaptic strength by quantal addition of structural modules.
Liu, Kang K L; Hagan, Michael F; Lisman, John E
2017-03-05
Memory storage involves activity-dependent strengthening of synaptic transmission, a process termed long-term potentiation (LTP). The late phase of LTP is thought to encode long-term memory and involves structural processes that enlarge the synapse. Hence, understanding how synapse size is graded provides fundamental information about the information storage capability of synapses. Recent work using electron microscopy (EM) to quantify synapse dimensions has suggested that synapses may structurally encode as many as 26 functionally distinct states, which correspond to a series of proportionally spaced synapse sizes. Other recent evidence using super-resolution microscopy has revealed that synapses are composed of stereotyped nanoclusters of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and scaffolding proteins; furthermore, synapse size varies linearly with the number of nanoclusters. Here we have sought to develop a model of synapse structure and growth that is consistent with both the EM and super-resolution data. We argue that synapses are composed of modules consisting of matrix material and potentially one nanocluster. LTP induction can add a trans-synaptic nanocluster to a module, thereby converting a silent module to an AMPA functional module. LTP can also add modules by a linear process, thereby producing an approximately 10-fold gradation in synapse size and strength.This article is part of the themed issue 'Integrating Hebbian and homeostatic plasticity'. © 2017 The Author(s).
Post surgical pain management with poly(ortho esters).
Barr, John; Woodburn, Kathryn W; Ng, Steven Y; Shen, Hui-Rong; Heller, Jorge
2002-10-16
Poly(ortho esters), POE, are synthetic bioerodible polymers that can be prepared as solid materials, or as viscous, injectable polymers. These materials have evolved through a number of families, and the latest member of this family, POE IV, is particularly well suited to drug delivery since latent acid is integrated into the polymer backbone, thereby, modulating surface erosion. POE IV predominantly undergoes surface erosion and is able to moderate drug release over periods from days to many months. One indication in which the POE IV polymer is currently being investigated is in sustained post-surgical pain management. The local anesthetic agent, mepivacaine, has been incorporated into a viscous, injectable POE IV and its potential to provide longer-acting anesthesia has been explored in non-clinical models.
Connecting with Teachers and Students through K-12 Outreach Activities
NASA Astrophysics Data System (ADS)
Chapman, Susan; Lindbo, David; Robinson, Clay
2014-05-01
The Soil Science Society of America has invested heavily in a significant outreach effort to reach teachers and students in the primary/secondary grades (K-12 grades in US/Canada) to raise awareness of soil as a critical resource. The SSSA K-12 committee has been charged with increasing interest and awareness of soil science as a scientific pursuit and career choice, and providing resources that integrate more information on soil science into biology, chemistry, physics, and earth science areas taught at multiple grade levels. Activities center around five main areas: assessment and standards, learning modules/lesson plans, website development, and books and materials, and partnership activities. Members (professionals and students) of SSSA are involved through committee participation, local events, materials review, and project development.
Apparatus configured for identification of a material and method of identifying a material
Slater, John M.; Crawford, Thomas M.; Frickey, Dean A.
2001-01-01
The present invention relates to an apparatus configured for identification of a material and method of identifying a material. One embodiment of the present invention provides an apparatus configured for identification of a material including a first region configured to receive a first sample and output a first spectrum responsive to exposure of the first sample to radiation; a signal generator configured to provide a reference signal having a reference frequency and a modulation signal having a modulation frequency; a modulator configured to selectively modulate the first spectrum using the modulation signal according to the reference frequency; a second region configured to receive a second sample and output a second spectrum responsive to exposure of the second sample to the first spectrum; and a detector configured to detect the second spectrum.
ERIC Educational Resources Information Center
Hoffman, Kathleen; Leupen, Sarah; Dowell, Kathy; Kephart, Kerrie; Leips, Jeff
2016-01-01
Redesigning undergraduate biology courses to integrate quantitative reasoning and skill development is critical to prepare students for careers in modern medicine and scientific research. In this paper, we report on the development, implementation, and assessment of stand-alone modules that integrate quantitative reasoning into introductory…
NASA Astrophysics Data System (ADS)
Wicht, A.; Bawamia, A.; Krüger, M.; Kürbis, Ch.; Schiemangk, M.; Smol, R.; Peters, A.; Tränkle, G.
2017-02-01
We present the status of our efforts to develop very compact and robust diode laser modules specifically suited for quantum optics experiments in the field and in space. The paper describes why hybrid micro-integration and GaAs-diode laser technology is best suited to meet the needs of such applications. The electro-optical performance achieved with hybrid micro-integrated, medium linewidth, high power distributed-feedback master-oscillator-power-amplifier modules and with medium power, narrow linewidth extended cavity diode lasers emitting at 767 nm and 780 nm are briefly described and the status of space relevant stress tests and space heritage is summarized. We also describe the performance of an ECDL operating at 1070 nm. Further, a novel and versatile technology platform is introduced that allows for integration of any type of laser system or electro-optical module that can be constructed from two GaAs chips. This facilitates, for the first time, hybrid micro-integration, e.g. of extended cavity diode laser master-oscillator-poweramplifier modules, of dual-stage optical amplifiers, or of lasers with integrated, chip-based phase modulator. As an example we describe the implementation of an ECDL-MOPA designed for experiments on ultra-cold rubidium and potassium atoms on board a sounding rocket and give basic performance parameters.
Ahmad, Badariah; Ramadas, Amutha; Kia Fatt, Quek; Md Zain, Anuar Zaini
2014-04-08
Diabetes education and self-care remains the cornerstone of diabetes management. There are many structured diabetes modules available in the United Kingdom, Europe and United States of America. Contrastingly, few structured and validated diabetes modules are available in Malaysia. This pilot study aims to develop and validate diabetes education material suitable and tailored for a multicultural society like Malaysia. The theoretical framework of this module was founded from the Health Belief Model (HBM). The participants were assessed using 6-item pre- and post-test questionnaires that measured some of the known HBM constructs namely cues to action, perceived severity and perceived benefit. Data was analysed using PASW Statistics 18.0. The pre- and post-test questionnaires were administered to 88 participants (31 males). In general, there was a significant increase in the total score in post-test (97.34 ± 6.13%) compared to pre-test (92.80 ± 12.83%) (p < 0.05) and a significant increase in excellent score (>85%) at post-test (84.1%) compared to pre-test (70.5%) (p < 0.05). There was an improvement in post-test score in 4 of 6 items tested. The remaining 2 items which measured the perceived severity and cues to action had poorer post-test score. The preliminary results from this pilot study suggest contextualised content material embedded within MY DEMO maybe suitable for integration with the existing diabetes education programmes. This was the first known validated diabetes education programme available in the Malay language.
NASA Astrophysics Data System (ADS)
Ng, Chee Hoe; Adnan, M.
2018-01-01
This research aims to investigate the effect of integrating STEM education through Project-based Inquiry Learning (PIL) and the users of the STEM modules which consists of five projects on topic Space in Year One Mathematics Syllabus in Kurikulum Standard Sekolah Rendah (KSSR) of Malaysia. STEM education in primary school focuses on the introduces and awareness of students about the importance of STEM education. The projects in STEM modules are covering the different ethnic cultures in Malaysia. The modules are designed using the four phases in PIL. Concepts and the explanation of STEM education on each project are emphasized and provided in the modules so the teachers able to carry out the projects by using the modules. By using the modules in primary Mathematics, the students and teachers will be more understanding on how to integrate the Mathematics’ concepts in STEM education.
Space Applications Industrial Laser System (SAILS)
NASA Technical Reports Server (NTRS)
Mccay, T. D.; Bible, J. B.; Mueller, R. E.
1993-01-01
A program is underway to develop a YAG laser based materials processing workstation to fly in the cargo bay of the Space Shuttle. This workstation, called Space Applications Industrial Laser System (SAILS), will be capable of cutting and welding steel, aluminum, and Inconel alloys of the type planned for use in constructing the Space Station Freedom. As well as demonstrating the ability of a YAG laser to perform remote (fiber-optic delivered) repair and fabrication operations in space, fundamental data will be collected on these interactions for comparison with terrestrial data and models. The flight system, scheduled to fly in 1996, will be constructed as three modules using standard Get-Away-Special (GAS) canisters. The first module holds the laser head and cooling system, while the second contains a high peak power electrical supply. The third module houses the materials processing workstation and the command and data acquisition subsystems. The laser head and workstation cansisters are linked by a fiber-optic cable to transmit the laser light. The team assembled to carry out this project includes Lumonics Industrial Products (laser), Tennessee Technological University (structural analysis and fabrication), Auburn University Center for Space Power (electrical engineering), University of Waterloo (low-g laser process consulting), and CSTAR/UTSI (data acquisition, control, software, integration, experiment design). This report describes the SAILS program and highlights recent activities undertaken at CSTAR.
Tuchman, Ellen; Hanley, Kathleen; Naegle, Madeline; More, Frederick; Bereket, Sewit; Gourevitch, Marc N
2017-01-01
The Substance Abuse Research and Education Training (SARET) program is funded by the National Institutes of Drug Abuse in 2006 as a novel approach to spark interest in substance abuse research among medical, dental, nursing, and social work graduate students through a Web-based curriculum and research mentorships. This report presents the initial integration of the intervention in a Master of Social Work (MSW) program, the components of the program, and the mixed-methods evaluation of its effect on students' attitudes towards substance abuse research and treatment. SARET comprises 2 main components: stipend-supported research mentorships and a Web-based module series, consisting of 6 interactive, multimedia modules addressing core SA research topics, delivered via course curricula and in the research mentorships. An initial evaluation was designed to assess SARET's acceptability and short-term impact on participants' interest in SA research. The components of this Web-based curriculum evaluation include focus group feedback on the relevance of the modules to SW students, number of courses into which the modules were integrated with number of module completions, changes in interest in SA research associated with module completion. The full series of Web-based modules has been integrated across several courses in the social work curriculum, and social work students have become integral participants in the summer mentored research experience. One hundred eighteen students completed at least 1 module and 42 students completed all 6 modules. Neurobiology, Screening, and Epidemiology were the most widely viewed modules. Students reported positive impact on their vision of SA-related clinical care, more positive attitudes about conducting research, and in some cases, change in career. The SARET program's modules and summer mentored research increased clinical and research interest related to SUDs, as well as interprofessional attitudes among social work students. Participants have shown some early research success. Longer-term follow-up will enable us to continue to assess the effectiveness of the program.
Optical Electronics. Electronics Module 9. Instructor's Guide.
ERIC Educational Resources Information Center
Franken, Bill
This module is the ninth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module, a parts/equipment list, and a cross reference table of instructional materials. Five instructional units cover: fiber optic cable; optical coupler; lasers and masers; optical displays;…
Electromechanical Devices and Controllers. Electronics Module 10. Instructor's Guide.
ERIC Educational Resources Information Center
Carter, Ed
This module is the tenth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module, a parts/equipment list, and a cross-reference table of instructional materials. Six instructional units cover: electromechanical control devices; programmable logic controllers (PLC);…
Organic Micro/Nanoscale Lasers.
Zhang, Wei; Yao, Jiannian; Zhao, Yong Sheng
2016-09-20
Micro/nanoscale lasers that can deliver intense coherent light signals at (sub)wavelength scale have recently captured broad research interest because of their potential applications ranging from on-chip information processing to high-throughput sensing. Organic molecular materials are a promising kind of ideal platform to construct high-performance microlasers, mainly because of their superiority in abundant excited-state processes with large active cross sections for high gain emissions and flexibly assembled structures for high-quality microcavities. In recent years, ever-increasing efforts have been dedicated to developing such organic microlasers toward low threshold, multicolor output, broadband tunability, and easy integration. Therefore, it is increasingly important to summarize this research field and give deep insight into the structure-property relationships of organic microlasers to accelerate the future development. In this Account, we will review the recent advances in organic miniaturized lasers, with an emphasis on tunable laser performances based on the tailorable microcavity structures and controlled excited-state gain processes of organic materials toward integrated photonic applications. Organic π-conjugated molecules with weak intermolecular interactions readily assemble into regular nanostructures that can serve as high-quality optical microcavities for the strong confinement of photons. On the basis of rational material design, a series of optical microcavities with different structures have been controllably synthesized. These microcavity nanostructures can be endowed with effective four-level dynamic gain processes, such as excited-state intramolecular charge transfer, excited-state intramolecular proton transfer, and excimer processes, that exhibit large dipole optical transitions for strongly active gain behaviors. By tailoring these excited-state processes with molecular/crystal engineering and external stimuli, people have effectively modulated the performances of organic micro/nanolasers. Furthermore, by means of controlled assembly and tunable laser performances, efficient outcoupling of microlasers has been successfully achieved in various organic hybrid microstructures, showing considerable potential for the integrated photonic applications. This Account starts by presenting an overview of the research evolution of organic microlasers in terms of microcavity resonators and energy-level gain. Then a series of strategies to tailor the microcavity structures and excited-state dynamics of organic nanomaterials for the modulation of lasing performances are highlighted. In the following part, we introduce the construction and advanced photonic functionalities of organic-microlaser-based hybrid structures and their applications in integrated nanophotonics. Finally, we provide our outlook on the current challenges as well as the future development of organic microlasers. It is anticipated that this Account will provide inspiration for the development of miniaturized lasers with desired performances by tailoring of excited-state processes and microcavity structures toward integrated photonic applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lagerwaard, Frank J.; Hoorn, Elles A.P. van der; Verbakel, Wilko
2009-09-01
Purpose: Volumetric modulated arc therapy (RapidArc [RA]; Varian Medical Systems, Palo Alto, CA) allows for the generation of intensity-modulated dose distributions by use of a single gantry rotation. We used RA to plan and deliver whole-brain radiotherapy (WBRT) with a simultaneous integrated boost in patients with multiple brain metastases. Methods and Materials: Composite RA plans were generated for 8 patients, consisting of WBRT (20 Gy in 5 fractions) with an integrated boost, also 20 Gy in 5 fractions, to Brain metastases, and clinically delivered in 3 patients. Summated gross tumor volumes were 1.0 to 37.5 cm{sup 3}. RA plans weremore » measured in a solid water phantom by use of Gafchromic films (International Specialty Products, Wayne, NJ). Results: Composite RA plans could be generated within 1 hour. Two arcs were needed to deliver the mean of 1,600 monitor units with a mean 'beam-on' time of 180 seconds. RA plans showed excellent coverage of planning target volume for WBRT and planning target volume for the boost, with mean volumes receiving at least 95% of the prescribed dose of 100% and 99.8%, respectively. The mean conformity index was 1.36. Composite plans showed much steeper dose gradients outside Brain metastases than plans with a conventional summation of WBRT and radiosurgery. Comparison of calculated and measured doses showed a mean gamma for double-arc plans of 0.30, and the area with a gamma larger than 1 was 2%. In-room times for clinical RA sessions were approximately 20 minutes for each patient. Conclusions: RA treatment planning and delivery of integrated plans of WBRT and boosts to multiple brain metastases is a rapid and accurate technique that has a higher conformity index than conventional summation of WBRT and radiosurgery boost.« less
Long-wavelength photonic integrated circuits and avalanche photodetectors
NASA Astrophysics Data System (ADS)
Tsou, Yi-Jen D.; Zaytsev, Sergey; Pauchard, Alexandre; Hummel, Steve; Lo, Yu-Hwa
2001-10-01
Fast-growing internet traffic volume require high data communication bandwidth over longer distances. Access network bottlenecks put pressure on short-range (SR) telecommunication systems. To effectively address these datacom and telecom market needs, low-cost, high-speed laser modules at 1310 to 1550 nm wavelengths and avalanche photodetectors are required. The great success of GaAs 850nm VCSEls for Gb/s Ethernet has motivated efforts to extend VCSEL technology to longer wavelengths in the 1310 and 1550 nm regimes. However, the technological challenges associated with materials for long wavelength VCSELs are tremendous. Even with recent advances in this area, it is believed that significant additional development is necessary before long wavelength VCSELs that meet commercial specifications will be widely available. In addition, the more stringent OC192 and OC768 specifications for single-mode fiber (SMF) datacom may require more than just a long wavelength laser diode, VCSEL or not, to address numerous cost and performance issues. We believe that photonic integrated circuits (PICs), which compactly integrate surface-emitting lasers with additional active and passive optical components with extended functionality, will provide the best solutions to today's problems. Photonic integrated circuits have been investigated for more than a decade. However, they have produced limited commercial impact to date primarily because the highly complicated fabrication processes produce significant yield and device performance issues. In this presentation, we will discuss a new technology platform of InP-based PICs compatible with surface-emitting laser technology, as well as a high data rate externally modulated laser module. Avalanche photodetectors (APDs) are the key component in the receiver to achieve high data rate over long transmission distance because of their high sensitivity and large gain- bandwidth product. We have used wafer fusion technology to achieve InGaAs/Si APDs with much greater potential than the traditional InGaAs/InP APDs. Preliminary results on their performance will be presented.
3D printed Lego®-like modular microfluidic devices based on capillary driving.
Nie, Jing; Gao, Qing; Qiu, Jing-Jiang; Sun, Miao; Liu, An; Shao, Lei; Fu, Jian-Zhong; Zhao, Peng; He, Yong
2018-03-12
The field of how to rapidly assemble microfluidics with modular components continuously attracts researchers' attention, however, extra efforts must be devoted to solving the problems of leaking and aligning between individual modules. This paper presents a novel type of modular microfluidic device, driven by capillary force. There is no necessity for a strict seal or special alignment, and its open structures make it easy to integrate various stents and reactants. The key rationale for this method is to print different functional modules with a low-cost three-dimensional (3D) printer, then fill the channels with capillary materials and assemble them with plugs like Lego ® bricks. This rapidly reconstructed modular microfluidic device consists of a variety of common functional modules and other personalized modules, each module having a unified standard interface for easy assembly. As it can be printed by a desktop 3D printer, the manufacturing process is simple and efficient, with controllable regulation of the flow channel scale. Through diverse combinations of different modules, a variety of different functions can be achieved, without duplicating the manufacturing process. A single module can also be taken out for testing and analysis. What's more, combined with basic circuit components, it can serve as a low-cost Lego ® -like modular microfluidic circuits. As a proof of concept, the modular microfluidic device has been successfully demonstrated and used for stent degradation and cell cultures, revealing the potential use of this method in both chemical and biological research.
NASA Astrophysics Data System (ADS)
Hanasaki, N.; Kanae, S.; Oki, T.; Shirakawa, N.
2007-10-01
To assess global water resources from the perspective of subannual variation in water resources and water use, an integrated water resources model was developed. In a companion report, we presented the global meteorological forcing input used to drive the model and two natural hydrological cycle modules, namely, the land surface hydrology module and the river routing module. Here, we present the remaining four modules, which represent anthropogenic activities: a crop growth module, a reservoir operation module, an environmental flow requirement module, and an anthropogenic withdrawal module. In addition, we discuss the results of a global water resources assessment using the integrated model. The crop growth module is a relatively simple model based on heat unit theory and potential biomass and harvest index concepts. The performance of the crop growth module was examined extensively because agricultural water comprises approximately 70% of total water withdrawal in the world. The estimated crop calendar showed good agreement with earlier reports for wheat, maize, and rice in major countries of production. The estimated irrigation water withdrawal also showed fair agreement with country statistics, but tended to underestimate countries in the Asian monsoon region. In the reservoir operation module, 452 major reservoirs with more than 1 km³ each of storage capacity store and release water according to their own rules of operation. Operating rules were determined for each reservoir using an algorithm that used currently available global data such as reservoir storage capacity, intended purposes, simulated inflow, and water demand in the lower reaches. The environmental flow requirement module was newly developed based on case studies from around the world. The integrated model closes both energy and water balances on land surfaces. Global water resources were assessed on a subannual basis using a newly devised index that locates water-stressed regions that were undetected in earlier studies. These regions, which are indicated by a gap in the subannual distribution of water resources and water use, include the Sahel, the Asian monsoon region, and southern Africa. The integrated model is applicable to assess various global environmental projections such as climate change.
Drosophila genetics in the classroom.
Sofer, W; Tompkins, L
1994-01-01
Drosophila has long been useful for demonstrating the principles of classical Mendelian genetics in the classroom. In recent years, the organism has also helped students understand biochemical and behavioral genetics. In this connection, this article describes the development of a set of integrated laboratory exercises and descriptive materials--a laboratory module--in biochemical genetics for use by high-school students. The module focuses on the Adh gene and its product, the alcohol dehydrogenase enzyme. Among other activities, students using the module get to measure alcohol tolerance and to assay alcohol dehydrogenase activity in Adh-negative and -positive flies. To effectively present the module in the classroom, teachers attend a month-long Dissemination Institute in the summer. During this period, they learn about other research activities that can be adapted for classroom use. One such activity that has proved popular with teachers and students utilizes Drosophila to introduce some of the concepts of behavioral genetics to the high-school student. By establishing closer interactions between high-school educators and research scientists, the gulf between the two communities can begin to be bridged. It is anticipated that the result of a closer relationship will be that the excitement and creativity of science will be more effectively conveyed to students.
Thermal Vacuum Chamber Repressurization with Instrument Purging
NASA Technical Reports Server (NTRS)
Woronowicz, Michael
2016-01-01
At the end of James Webb Space Telescope (JWST) OTIS (Optical Telescope Element-OTE-Integrated Science Instrument Module-ISIM) cryogenic vacuum testing in NASA Johnson Space Centers (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are mooting the idea that chamber particulate material stirred up by the repressurization process may be kept from falling into the ISIM interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This memo describes development of a series of models designed to describe this process. These are strung together in tandem to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.
Thermal Vacuum Chamber Repressurization with Instrument Purging
NASA Technical Reports Server (NTRS)
Woronowicz, Michael
2017-01-01
At the end of James Webb Space Telescope (JWST) OTIS (Optical Telescope Element-OTE-Integrated Science Instrument Module-ISIM) cryogenic vacuum testing in NASA Johnson Space Centers (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are mooting the idea that chamber particulate material stirred up by the repressurization process may be kept from falling into the ISIM interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This memo describes development of a series of models designed to describe this process. These are strung together in tandem to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephenson, C. A., E-mail: cstephe3@nd.edu; Stillwell, R. A.; Wistey, M. A.
Compact optical interconnects require efficient lasers and modulators compatible with silicon. Ab initio modeling of Ge{sub 1−x}C{sub x} (x = 0.78%) using density functional theory with HSE06 hybrid functionals predicts a splitting of the conduction band at Γ and a strongly direct bandgap, consistent with band anticrossing. Photoreflectance of Ge{sub 0.998}C{sub 0.002} shows a bandgap reduction supporting these results. Growth of Ge{sub 0.998}C{sub 0.002} using tetrakis(germyl)methane as the C source shows no signs of C-C bonds, C clusters, or extended defects, suggesting highly substitutional incorporation of C. Optical gain and modulation are predicted to rival III–V materials due to a larger electronmore » population in the direct valley, reduced intervalley scattering, suppressed Auger recombination, and increased overlap integral for a stronger fundamental optical transition.« less
2017-03-17
United Launch Alliance (ULA) technicians monitor the progress as the payload fairing containing the Orbital ATK Cygnus pressurized cargo module is lowered onto the Centaur upper stage, or second stage, of the ULA Atlas V rocket in the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
Modelling of polymer photodegradation for solar cell modules
NASA Technical Reports Server (NTRS)
Somersall, A. C.; Guillet, J. E.
1981-01-01
A computer program developed to model and calculate by numerical integration the varying concentrations of chemical species formed during photooxidation of a polymeric material over time, using as input data a choice set of elementary reactions, corresponding rate constants and a convenient set of starting conditions is evaluated. Attempts were made to validate the proposed mechanism by experimentally monitoring the photooxidation products of small liquid alkane which are useful starting models for ethylene segments of polymers like EVA. The model system proved in appropriate for the intended purposes. Another validation model is recommended.
Crystallography of biological fluid as a method for evaluating its physicochemical characteristics.
Martusevich, A K; Kamakin, N F
2007-03-01
Using an integral qualitative and quantitative approach to the studies of initiation of the biological material crystallogenesis, we showed in experiments with normal human saliva that the external characteristics of biological fluid (pH, osmolality, and environmental temperature) determine the results of crystallization (tesigraphic facies). The main external (macroenvironment) and inner (microenvironment) factors of biological fluid crystal formation, determining specific features of the tesigraphic facies, were distinguished and classified. The informative value of differential analysis of biomaterial properties by means of modulating the environmental conditions is established.
2017-03-17
The payload fairing containing the Orbital ATK Cygnus pressurized cargo module is lifted by crane at the United Launch Alliance (ULA) Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The payload will be hoisted up and mated to the ULA Atlas V rocket. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
Atlas_V_OA-7_Payload_Mate_to_Booster
2017-03-17
The payload fairing containing the Orbital ATK Cygnus pressurized cargo module is lifted and mated onto the Centaur upper stage, or second stage, of the United Launch Alliance (ULA) rocket in the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
2017-03-17
The payload fairing containing the Orbital ATK Cygnus pressurized cargo module is hoisted up by crane at the United Launch Alliance (ULA) Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The payload will be mated to the ULA Atlas V rocket. The Orbital ATK CRS-7 commercial resupply services mission to the International Space Station is scheduled to launch atop the Atlas V from pad 41. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station.
2013-06-24
ISS036-E-019783 (24 June 2013) --- In the International Space Station’s Destiny laboratory, a fisheye lens attached to an electronic still camera was used to capture this image of NASA astronaut Karen Nyberg, Expedition 36 flight engineer, as she conducts a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.
Everaert, Jonas; Grahek, Ivan; Koster, Ernst H W
2017-06-01
Deficient cognitive control over emotional material and cognitive biases are important mechanisms underlying depression, but the interplay between these emotionally distorted cognitive processes in relation to depressive symptoms is not well understood. This study investigated the relations among deficient cognitive control of emotional information (i.e. inhibition, shifting, and updating difficulties), cognitive biases (i.e. negative attention and interpretation biases), and depressive symptoms. Theory-driven indirect effect models were constructed, hypothesising that deficient cognitive control over emotional material predicts depressive symptoms through negative attention and interpretation biases. Bootstrapping analyses demonstrated that deficient inhibitory control over negative material was related to negative attention bias which in turn predicted a congruent bias in interpretation and subsequently depressive symptoms. Both shifting and updating impairments in response to negative material had an indirect effect on depression severity through negative interpretation bias. No evidence was found for direct effects of deficient cognitive control over emotional material on depressive symptoms. These findings may help to formulate an integrated understanding of the cognitive foundations of depressive symptoms.
NASA Technical Reports Server (NTRS)
Crouch, Myscha; Carswell, Bill; Farmer, Jeff; Rose, Fred; Tidwell, Paul
1999-01-01
The Material Science Research Rack 1 (MSRR-1) of the Material Science Research Facility (MSRF) contains an Experiment Module (EM) being developed collaboratively by NASA and the European Space Agency (ESA). This NASA/ESA EM will accommodate several different removable and replaceable Module Inserts (MIs) which are installed on orbit. Two of the NASA MIs being developed for specific material science investigations are described herein.
Triggerable electro-optic amplitude modulator bias stabilizer for integrated optical devices
Conder, A.D.; Haigh, R.E.; Hugenberg, K.F.
1995-09-26
An improved Mach-Zehnder integrated optical electro-optic modulator is achieved by application and incorporation of a DC bias box containing a laser synchronized trigger circuit, a DC ramp and hold circuit, a modulator transfer function negative peak detector circuit, and an adjustable delay circuit. The DC bias box ramps the DC bias along the transfer function curve to any desired phase or point of operation at which point the RF modulation takes place. 7 figs.
Triggerable electro-optic amplitude modulator bias stabilizer for integrated optical devices
Conder, Alan D.; Haigh, Ronald E.; Hugenberg, Keith F.
1995-01-01
An improved Mach-Zehnder integrated optical electro-optic modulator is achieved by application and incorporation of a DC bias box containing a laser synchronized trigger circuit, a DC ramp and hold circuit, a modulator transfer function negative peak detector circuit, and an adjustable delay circuit. The DC bias box ramps the DC bias along the transfer function curve to any desired phase or point of operation at which point the RF modulation takes place.
Integrated optical modulator for signal up-conversion over radio-on-fiber link.
Kim, Woo-Kyung; Kwon, Soon-Woo; Jeong, Woo-Jin; Son, Geun-Sik; Lee, Kwang-Hyun; Choi, Woo-Young; Yang, Woo-Seok; Lee, Hyung-Man; Lee, Han-Young
2009-02-16
An integrated optical modulator, which consists of a dual-sideband suppressed carrier (DSB-SC) modulator cascaded with a single-sideband (SSB) modulator, is proposed for signal up-conversion over Radio-on-Fiber. Utilizing a single-drive domain inverted structure in both modulators, balanced modulations were obtained without complicated radio frequency (RF) driving circuits and delicate RF phase adjustments. Intermediate frequency (IF) band signal was up-conversed to 60GHz band by using the fabricated device and was transmitted over optical fiber. Experiment results show that the proposed device enables millimeter wave generation and signal transmission without any power penalty caused by chromatic dispersion.
System approach to the analysis of an integrated oxy-fuel combustion power plant
NASA Astrophysics Data System (ADS)
Ziębik, Andrzej; Gładysz, Paweł
2014-09-01
Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2. Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the `input-output' method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.
Welding Materials. Pre-Apprenticeship Phase 1 Training.
ERIC Educational Resources Information Center
Lane Community Coll., Eugene, OR.
This student training module on welding materials is one of three modules (see CE 032 889-890) on welding developed for Pre-Apprenticeship Phase 1 Training. (A companion instructor's guide is available separately as CE 032 888.) The modules are designed to introduce trade knowledge and skills to the student. This module contains a cover sheet…
Nuclear Technology. Course 31: Quality Assurance Practices. Module 31-5, Nonconforming Materials.
ERIC Educational Resources Information Center
Pritchard, Jim; Espy, John
This fifth in a series of eight modules for a course titled Quality Assurance Practices describes the essential elements of a nonconforming material control system, including purpose and application. The module follows a typical format that includes the following sections: (1) introduction, (2) module prerequisites, (3) objectives, (4) notes to…
Receivers and Transmitters. Electronics Module 6. Instructor's Guide.
ERIC Educational Resources Information Center
Everett, Jim
This module is the sixth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module and a cross-reference table of instructional materials. Two instructional units cover: (1) AM/FM transmitter and receiver basics; and (2) satellite systems, antennas, and analyzers.…
Safety Features of Material and Personnel Movement Devices. Module SH-25. Safety and Health.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
This student module on safety features of material and personnel movement devices is one of 50 modules concerned with job safety and health. This module covers safe conditions and operating practices for conveyors, elevators, escalators, moving walks, manlifts, forklifts, and motorized hand trucks. Following the introduction, 10 objectives (each…
Biomaterials-Based Electronics: Polymers and Interfaces for Biology and Medicine
Muskovich, Meredith; Bettinger, Christopher J.
2012-01-01
Advanced polymeric biomaterials continue to serve as a cornerstone of new medical technologies and therapies. The vast majority of these materials, both natural and synthetic, interact with biological matter without direct electronic communication. However, biological systems have evolved to synthesize and employ naturally-derived materials for the generation and modulation of electrical potentials, voltage gradients, and ion flows. Bioelectric phenomena can be interpreted as potent signaling cues for intra- and inter-cellular communication. These cues can serve as a gateway to link synthetic devices with biological systems. This progress report will provide an update on advances in the application of electronically active biomaterials for use in organic electronics and bio-interfaces. Specific focus will be granted to the use of natural and synthetic biological materials as integral components in technologies such as thin film electronics, in vitro cell culture models, and implantable medical devices. Future perspectives and emerging challenges will also be highlighted. PMID:23184740
Synthesis of the thermoelectric nanopowder recovered from the used thermoelectric modules.
Lee, Kun-Jae; Jin, Yun-Ho; Kong, Man-Sik
2014-10-01
We fabricated the thermoelectric powder using the used thermoelectric modules in a vehicle. As a starting material, the used thermoelectric modules were collected and separated to substrate, electrode, solder, and thermoelectric parts by a thermal process. The separation process was performed in a wet process at the critical temperature. The solder in the module was the neighbor part of the thermoelectric material with the lowest melting temperature in the module. We focused on the thermal property of the solder to separate the thermoelectric chips in the module. After the separation process, we prepared the pure thermoelectric material by the chemical etching for an impurity removal. Also the thermoelectric nanopowder was fabricated by a chemical reduction reaction using the recycled thermoelectric materials. The recovered nanopowder was confirmed to the phase of bismuth telluride (Bi2Te3) with the particle size of -15 nm.
Real time outdoor exposure testing of solar cell modules and component materials
NASA Technical Reports Server (NTRS)
Anagnostou, E.; Forestieri, A. F.
1977-01-01
Plastic samples, solar cell modules, and sub-modules were exposed at test sites in Florida, Arizona, Puerto Rico, and Cleveland, Ohio, in order to determine materials suitable for use in solar cell modules with a proposed 20-year lifetime. Various environments were encountered including subtropical, subtropical with a sea air atmosphere, desert, rain forest, normal urban, and urban-polluted. The samples were exposed for periods up to six months. Materials found not suitable were polyurethane, polyester, Kapton, Mylar, and UV-stabilized Lexan. Suitable materials were acrylic, FEP-A, and glass. The results of exposure of polyvinylidene fluoride were dependent on the specific formulation, but several types appear suitable. RTV silicone rubber (clear) appears to pick up and hold dirt both as a free film and as a potting medium for modules. The results indicate that dirt accumulation and cleanability are important factors in the selection of solar cell module covers and encapsulants.
InTeGrate: Transforming the Teaching of Geoscience and Sustainability
NASA Astrophysics Data System (ADS)
Blockstein, D.; Manduca, C. A.; Bralower, T. J.; Castendyk, D.; Egger, A. E.; Gosselin, D. C.; Iverson, E. A.; Matson, P. A.; MacGregor, J.; Mcconnell, D. A.; Mogk, D. W.; Nevle, R. J.; Oches, E. A.; Steer, D. N.; Wiese, K.
2012-12-01
InTeGrate is an NSF-funded community project to improve geoscience literacy and build a workforce that can apply geoscience principles to address societal issues. Three workshops offered this year by InTeGrate and its partner, On the Cutting Edge, addressed strategies for bringing together geoscience and sustainability within geoscience courses and programs, in interdisciplinary courses and programs, and in courses and programs in other disciplines or schools including arts and humanities, health science, and business. Participants in all workshops described the power of teaching geoscience in the context of sustainability and the utility of this approach in engaging students with geoscience, including student populations not traditionally represented in the sciences. Faculty involved in both courses and programs seek to teach important skills including the ability to think about systems and to make connections between local observations and challenges and global phenomena and issues. Better articulation of these skills, including learning outcomes and assessments, as well as documenting the relationship between these skills and employment opportunities were identified as important areas for further work. To support widespread integration of geoscience and sustainability concepts, these workshops initiated collections describing current teaching activities, courses, and programs. InTeGrate will continue to build these collections in collaboration with On the Cutting Edge and Building Strong Geoscience Departments, and through open contributions by individual faculty and programs. In addition, InTeGrate began developing new teaching modules and courses. Materials for use in introductory geoscience and environmental science/studies courses, distance learning courses, and courses for education majors are being developed and tested by teams of faculty drawn from at least three institutions, including several members from two-year colleges. An assessment team is assisting the development teams in incorporation of research-based teaching methods and embedded assessments to document learning. The assessment team will also evaluate the success of these materials in meeting learning outcomes prior to broad dissemination. Additional opportunities for faculty to propose and develop needed materials are currently available.
Prinz, P; Ronacher, B
2002-08-01
The temporal resolution of auditory receptors of locusts was investigated by applying noise stimuli with sinusoidal amplitude modulations and by computing temporal modulation transfer functions. These transfer functions showed mostly bandpass characteristics, which are rarely found in other species at the level of receptors. From the upper cut-off frequencies of the modulation transfer functions the minimum integration times were calculated. Minimum integration times showed no significant correlation to the receptor spike rates but depended strongly on the body temperature. At 20 degrees C the average minimum integration time was 1.7 ms, dropping to 0.95 ms at 30 degrees C. The values found in this study correspond well to the range of minimum integration times found in birds and mammals. Gap detection is another standard paradigm to investigate temporal resolution. In locusts and other grasshoppers application of this paradigm yielded values of the minimum detectable gap widths that are approximately twice as large than the minimum integration times reported here.
Instructor satisfaction with a technology-based resource for diabetes education.
Hall, Deanne L; Corman, Shelby L; Drab, Scott R; Meyer, Susan M; Smith, Randall B
2009-05-27
To evaluate instructor use patterns and satisfaction with DM Educate, a comprehensive, Web-based diabetes course. Instructors completed a post-course survey instrument to assess their use of course materials and components, as well as satisfaction with the course content, design, and technology utilized, and to solicit their suggestions for additional content areas. Thirty-eight percent of respondents utilized DM Educate as a standalone elective and 62% had integrated materials into existing courses. The pharmacotherapy module was the most utilized at 91% and slide sets were the most utilized course components at 63%. All instructors stated that they would use the course again the following year. Suggestions for improvement included incorporation of more active-learning activities and patient cases. Instructors' were highly satisfied with the course materials and technology used by DM Educate, a Web-based diabetes education course, and indicated they were able to customize the course materials both to establish new courses and supplement existing courses. All instructors planned to use the course again.
NASA Astrophysics Data System (ADS)
Giacalone, Philip L.
1993-06-01
The design of the Intelsat VII surface tension propellant management device (PMD) (an all-welded assembly consisting of about 100 individual components) was developed using a modular design approach that allowed the complex PMD assembly to be divided into smaller modules. The modular approach reduces manufacturing-related technical and schedule risks and allows many components and assemblies to be processed in parallel, while also facilitating the incorporation of quality assurance tests at all critical PMD subassembly levels. The baseline PMD assembly is made from titanium and stainless steel materials. In order to obtain a 100 percent titanium PMD, a new, state-of-the-art fine mesh titanium screen material was developed, tested, and qualified for use as an alternaltive to the stainless steel screen material. The Ti based screen material demonstrated a high level of bubble point performance. It was integrated into a PMD assembly and was successfully qualification tested at the tank assembly level.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Peijun; Weimer, Matthew S.; Emery, Jonathan D.
Actively tunable optical transmission through artificial metamaterials holds great promise for next-generation nanophotonic devices and metasurfaces. Plasmonic nanostructures and phase change materials have been extensively studied to this end due to their respective strong interactions with light and tunable dielectric constants under external stimuli. Seamlessly integrating plasmonic components with phase change materials, as demonstrated in the present work, can facilitate phase change by plasmonically enabled light confinement and meanwhile make use of the high sensitivity of plasmon resonances to the variation of dielectric constant associated with the phase change. The hybrid platform here is composed of plasmonic indium tin-oxide nanorodmore » arrays (ITO-NRAs) conformally coated with an ultrathin layer of a prototypical phase change material, vanadium dioxide (VO2), which enables all-optical modulation of the infrared as well as the visible spectral ranges. The interplay between the intrinsic plasmonic nonlinearity of ITO-NRAs and the phase transition induced permittivity change of VO2 gives rise to spectral and temporal responses that cannot be achieved with individual material components alone.« less
Reliability analysis of laminated CMC components through shell subelement techniques
NASA Technical Reports Server (NTRS)
Starlinger, Alois; Duffy, Stephen F.; Gyekenyesi, John P.
1992-01-01
An updated version of the integrated design program Composite Ceramics Analysis and Reliability Evaluation of Structures (C/CARES) was developed for the reliability evaluation of ceramic matrix composites (CMC) laminated shell components. The algorithm is now split into two modules: a finite-element data interface program and a reliability evaluation algorithm. More flexibility is achieved, allowing for easy implementation with various finite-element programs. The interface program creates a neutral data base which is then read by the reliability module. This neutral data base concept allows easy data transfer between different computer systems. The new interface program from the finite-element code Matrix Automated Reduction and Coupling (MARC) also includes the option of using hybrid laminates (a combination of plies of different materials or different layups) and allows for variations in temperature fields throughout the component. In the current version of C/CARES, a subelement technique was implemented, enabling stress gradients within an element to be taken into account. The noninteractive reliability function is now evaluated at each Gaussian integration point instead of using averaging techniques. As a result of the increased number of stress evaluation points, considerable improvements in the accuracy of reliability analyses were realized.
Linear induction accelerators made from pulse-line cavities with external pulse injection.
Smith, I
1979-06-01
Two types of linear induction accelerator have been reported previously. In one, unidirectional voltage pulses are generated outside the accelerator and injected into the accelerator cavity modules, which contain ferromagnetic material to reduce energy losses in the form of currents induced, in parallel with the beam, in the cavity structure. In the other type, the accelerator cavity modules are themselves pulse-forming lines with energy storage and switches; parallel current losses are made zero by the use of circuits that generate bidirectional acceleration waveforms with a zero voltage-time integral. In a third type of design described here, the cavities are externally driven, and 100% efficient coupling of energy to the beam is obtained by designing the external pulse generators to produce bidirectional voltage waveforms with zero voltage-time integral. A design for such a pulse generator is described that is itself one hundred percent efficient and which is well suited to existing pulse power techniques. Two accelerator cavity designs are described that can couple the pulse from such a generator to the beam; one of these designs provides voltage doubling. Comparison is made between the accelerating gradients that can be obtained with this and the preceding types of induction accelerator.
Oguntosin, Victoria W; Mori, Yoshiki; Kim, Hyejong; Nasuto, Slawomir J; Kawamura, Sadao; Hayashi, Yoshikatsu
2017-01-01
We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM). Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realized by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale. Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton. The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable, wearable, and portable systems are required to be customized for individuals with specific motor impairments.
Oguntosin, Victoria W.; Mori, Yoshiki; Kim, Hyejong; Nasuto, Slawomir J.; Kawamura, Sadao; Hayashi, Yoshikatsu
2017-01-01
We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM). Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realized by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale. Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton. The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable, wearable, and portable systems are required to be customized for individuals with specific motor impairments. PMID:28736514
ATM test and integration. [Skylab Apollo Telescope Mount
NASA Technical Reports Server (NTRS)
Moore, J. W.; Mitchell, J. R.
1974-01-01
The test and checkout philosophy of the test program for the Skylab ATM module and the overall test flow including in-process, post-manufacturing, vibration, thermal vacuum, and prelaunch checkout activities are described. Capabilities and limitations of the test complex and its use of automation are discussed. Experiences with the organizational principle of using a dedicated test team for all checkout activities are reported. Material on the development of the ATM subsystems, the experimental program and the requirements of the scientific community, and the integration and verification of the complex systems/subsystems of the ATM are presented. The performance of the ATM test program in such areas as alignment, systems and subsystems, contamination control, and experiment operation is evaluated. The conclusions and recommendations resulting from the ATM test program are enumerated.
ERIC Educational Resources Information Center
Williams, Elmer; Dalton, Don
This 12-hour module of instruction is designed to help undergraduates in social studies methods courses integrate economics education into the elementary school social studies curriculum. The major purposes of the module are to (1) demonstrate how economics concepts can be integrated into social studies instruction, (2) reinforce or extend teacher…
Technical Reliability Studies. EOS/ESD Technology Abstracts
1982-01-01
RESISTANT BIPOLAR TRANSISTOR DESIGN AND ITS APPLICATIONS TO LINEAR INTEGRATED CIRCUITS 16145 MODULE ELECTROSTATIC DISCHARGE SIMULATOR 15786 SOME...T.M. 16476 STATIC DISCHARGE MODELING TECHNIQUES FOR EVALUATION OF INTEGRATED (FET) CIRCUIT DESTRUCTION 16145 MODULE ELECTAOSTATIC DISCHARGE SIMULATOR...PLASTIC LSI CIRCUITS PRklE, L.A., II 16145 MODULE ELECTROSTATIC DISCHARGE SIMULATOR PRICE, R.D. 13455 EVALUATION OF PLASTIC LSI CIRCUITS PSHAENICH, A
Electron tunneling infrared sensor module with integrated control circuitry
NASA Technical Reports Server (NTRS)
Boyadzhyan-Sevak, Vardkes V. (Inventor)
2001-01-01
In an integrated electron tunneling sensor, an automatic tunneling control circuit varies a high voltage bias applied to the sensor deflection electrode in response to changes in sensor output to maintain the proper gap between the sensor tip and membrane. The control circuit ensures stable tunneling activity in the presence of large signals and other disturbances to the sensor. Output signals from the module may be derived from the amplified sensor output. The integrated sensor module is particularly well adapted for use in blood glucose measurement and monitoring system.
An approach to developing an integrated pyroprocessing simulator
NASA Astrophysics Data System (ADS)
Lee, Hyo Jik; Ko, Won Il; Choi, Sung Yeol; Kim, Sung Ki; Kim, In Tae; Lee, Han Soo
2014-02-01
Pyroprocessing has been studied for a decade as one of the promising fuel recycling options in Korea. We have built a pyroprocessing integrated inactive demonstration facility (PRIDE) to assess the feasibility of integrated pyroprocessing technology and scale-up issues of the processing equipment. Even though such facility cannot be replaced with a real integrated facility using spent nuclear fuel (SF), many insights can be obtained in terms of the world's largest integrated pyroprocessing operation. In order to complement or overcome such limited test-based research, a pyroprocessing Modelling and simulation study began in 2011. The Korea Atomic Energy Research Institute (KAERI) suggested a Modelling architecture for the development of a multi-purpose pyroprocessing simulator consisting of three-tiered models: unit process, operation, and plant-level-model. The unit process model can be addressed using governing equations or empirical equations as a continuous system (CS). In contrast, the operation model describes the operational behaviors as a discrete event system (DES). The plant-level model is an integrated model of the unit process and an operation model with various analysis modules. An interface with different systems, the incorporation of different codes, a process-centered database design, and a dynamic material flow are discussed as necessary components for building a framework of the plant-level model. As a sample model that contains methods decoding the above engineering issues was thoroughly reviewed, the architecture for building the plant-level-model was verified. By analyzing a process and operation-combined model, we showed that the suggested approach is effective for comprehensively understanding an integrated dynamic material flow. This paper addressed the current status of the pyroprocessing Modelling and simulation activity at KAERI, and also predicted its path forward.
An approach to developing an integrated pyroprocessing simulator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Hyo Jik; Ko, Won Il; Choi, Sung Yeol
Pyroprocessing has been studied for a decade as one of the promising fuel recycling options in Korea. We have built a pyroprocessing integrated inactive demonstration facility (PRIDE) to assess the feasibility of integrated pyroprocessing technology and scale-up issues of the processing equipment. Even though such facility cannot be replaced with a real integrated facility using spent nuclear fuel (SF), many insights can be obtained in terms of the world's largest integrated pyroprocessing operation. In order to complement or overcome such limited test-based research, a pyroprocessing Modelling and simulation study began in 2011. The Korea Atomic Energy Research Institute (KAERI) suggestedmore » a Modelling architecture for the development of a multi-purpose pyroprocessing simulator consisting of three-tiered models: unit process, operation, and plant-level-model. The unit process model can be addressed using governing equations or empirical equations as a continuous system (CS). In contrast, the operation model describes the operational behaviors as a discrete event system (DES). The plant-level model is an integrated model of the unit process and an operation model with various analysis modules. An interface with different systems, the incorporation of different codes, a process-centered database design, and a dynamic material flow are discussed as necessary components for building a framework of the plant-level model. As a sample model that contains methods decoding the above engineering issues was thoroughly reviewed, the architecture for building the plant-level-model was verified. By analyzing a process and operation-combined model, we showed that the suggested approach is effective for comprehensively understanding an integrated dynamic material flow. This paper addressed the current status of the pyroprocessing Modelling and simulation activity at KAERI, and also predicted its path forward.« less
Zianni, Xanthippi; Jean, Valentin; Termentzidis, Konstantinos; Lacroix, David
2014-11-21
We report on scaling behavior of the thermal conductivity of width-modulated nanowires and nanofilms that have been studied with the phonon Monte Carlo technique. It has been found that the reduction of the thermal conductivity scales with the nanostructure transmissivity, a property entirely determined by the modulation geometry, irrespectively of the material choice. Tuning of the thermal conductivity is possible by the nanostructure width-modulation without strict limitations for the modulation profile. In addition, a very significant constriction thermal resistance due to width-discontinuity has been identified, in analogy to the contact thermal resistance between two dissimilar materials. The constriction thermal resistance also scales with the modulated nanostructure transmissivity. Our conclusions are generic indicating that a wide range of materials can be used for the modulated nanostructures. Direct heat flow control can be provided by designing the nanostructure width-modulation.
NASA Astrophysics Data System (ADS)
Fu, Enjin
Demand for more bandwidth is rapidly increasing, which is driven by data intensive applications such as high-definition (HD) video streaming, cloud storage, and terascale computing applications. Next-generation high-performance computing systems require power efficient chip-to-chip and intra-chip interconnect yielding densities on the order of 1Tbps/cm2. The performance requirements of such system are the driving force behind the development of silicon integrated optical interconnect, providing a cost-effective solution for fully integrated optical interconnect systems on a single substrate. Compared to conventional electrical interconnect, optical interconnects have several advantages, including frequency independent insertion loss resulting in ultra wide bandwidth and link latency reduction. For high-speed optical transmitter modules, the optical modulator is a key component of the optical I/O channel. This thesis presents a silicon integrated optical transmitter module design based on a novel silicon HBT-based carrier injection electroabsorption modulator (EAM), which has the merits of wide optical bandwidth, high speed, low power, low drive voltage, small footprint, and high modulation efficiency. The structure, mechanism, and fabrication of the modulator structure will be discussed which is followed by the electrical modeling of the post-processed modulator device. The design and realization of a 10Gbps monolithic optical transmitter module integrating the driver circuit architecture and the HBT-based EAM device in a 130nm BiCMOS process is discussed. For high power efficiency, a 6Gbps ultra-low power driver IC implemented in a 130nm BiCMOS process is presented. The driver IC incorporates an integrated 27-1 pseudo-random bit sequence (PRBS) generator for reliable high-speed testing, and a driver circuit featuring digitally-tuned pre-emphasis signal strength. With outstanding drive capability, the driver module can be applied to a wide range of carrier injection modulators and light-emitting diodes (LED) with drive voltage requirements below 1.5V. Measurement results show an optical link based on a 70MHz red LED work well at 300Mbps by using the pre-emphasis driver module. A traveling wave electrode (TWE) modulator structure is presented, including a novel design methodology to address process limitations imposed by a commercial silicon fabrication technology. Results from 3D full wave EM simulation demonstrate the application of the design methodology to achieve specifications, including phase velocity matching, insertion loss, and impedance matching. Results show the HBT-based TWE-EAM system has the bandwidth higher than 60GHz.
Integrating Software Modules For Robot Control
NASA Technical Reports Server (NTRS)
Volpe, Richard A.; Khosla, Pradeep; Stewart, David B.
1993-01-01
Reconfigurable, sensor-based control system uses state variables in systematic integration of reusable control modules. Designed for open-architecture hardware including many general-purpose microprocessors, each having own local memory plus access to global shared memory. Implemented in software as extension of Chimera II real-time operating system. Provides transparent computing mechanism for intertask communication between control modules and generic process-module architecture for multiprocessor realtime computation. Used to control robot arm. Proves useful in variety of other control and robotic applications.
An Integrated Simulation Module for Cyber-Physical Automation Systems †
Ferracuti, Francesco; Freddi, Alessandro; Monteriù, Andrea; Prist, Mariorosario
2016-01-01
The integration of Wireless Sensors Networks (WSNs) into Cyber Physical Systems (CPSs) is an important research problem to solve in order to increase the performances, safety, reliability and usability of wireless automation systems. Due to the complexity of real CPSs, emulators and simulators are often used to replace the real control devices and physical connections during the development stage. The most widespread simulators are free, open source, expandable, flexible and fully integrated into mathematical modeling tools; however, the connection at a physical level and the direct interaction with the real process via the WSN are only marginally tackled; moreover, the simulated wireless sensor motes are not able to generate the analogue output typically required for control purposes. A new simulation module for the control of a wireless cyber-physical system is proposed in this paper. The module integrates the COntiki OS JAva Simulator (COOJA), a cross-level wireless sensor network simulator, and the LabVIEW system design software from National Instruments. The proposed software module has been called “GILOO” (Graphical Integration of Labview and cOOja). It allows one to develop and to debug control strategies over the WSN both using virtual or real hardware modules, such as the National Instruments Real-Time Module platform, the CompactRio, the Supervisory Control And Data Acquisition (SCADA), etc. To test the proposed solution, we decided to integrate it with one of the most popular simulators, i.e., the Contiki OS, and wireless motes, i.e., the Sky mote. As a further contribution, the Contiki Sky DAC driver and a new “Advanced Sky GUI” have been proposed and tested in the COOJA Simulator in order to provide the possibility to develop control over the WSN. To test the performances of the proposed GILOO software module, several experimental tests have been made, and interesting preliminary results are reported. The GILOO module has been applied to a smart home mock-up where a networked control has been developed for the LED lighting system. PMID:27164109
An Integrated Simulation Module for Cyber-Physical Automation Systems.
Ferracuti, Francesco; Freddi, Alessandro; Monteriù, Andrea; Prist, Mariorosario
2016-05-05
The integration of Wireless Sensors Networks (WSNs) into Cyber Physical Systems (CPSs) is an important research problem to solve in order to increase the performances, safety, reliability and usability of wireless automation systems. Due to the complexity of real CPSs, emulators and simulators are often used to replace the real control devices and physical connections during the development stage. The most widespread simulators are free, open source, expandable, flexible and fully integrated into mathematical modeling tools; however, the connection at a physical level and the direct interaction with the real process via the WSN are only marginally tackled; moreover, the simulated wireless sensor motes are not able to generate the analogue output typically required for control purposes. A new simulation module for the control of a wireless cyber-physical system is proposed in this paper. The module integrates the COntiki OS JAva Simulator (COOJA), a cross-level wireless sensor network simulator, and the LabVIEW system design software from National Instruments. The proposed software module has been called "GILOO" (Graphical Integration of Labview and cOOja). It allows one to develop and to debug control strategies over the WSN both using virtual or real hardware modules, such as the National Instruments Real-Time Module platform, the CompactRio, the Supervisory Control And Data Acquisition (SCADA), etc. To test the proposed solution, we decided to integrate it with one of the most popular simulators, i.e., the Contiki OS, and wireless motes, i.e., the Sky mote. As a further contribution, the Contiki Sky DAC driver and a new "Advanced Sky GUI" have been proposed and tested in the COOJA Simulator in order to provide the possibility to develop control over the WSN. To test the performances of the proposed GILOO software module, several experimental tests have been made, and interesting preliminary results are reported. The GILOO module has been applied to a smart home mock-up where a networked control has been developed for the LED lighting system.
Long term thermoelectric module testing system.
D'Angelo, Jonathan; Hogan, Timothy
2009-10-01
Thermoelectric generators can be used for converting waste heat into electric power. Significant interest in developing new materials in recent years has led to the discovery of several promising thermoelectrics, however, there can be considerable challenges in developing the materials into working devices. Testing and feedback is needed at each step to gain valuable information for identification of difficulties, quality of the materials and modules, repeatability in fabrication, and longevity of the devices. This paper describes a long-term module testing system for monitoring the output power of a module over extended testing times. To evaluate the system, we have tested commercially available thermoelectric modules over a one month time period.
Negative Emotion Does Not Modulate Rapid Feature Integration Effects
Trübutschek, Darinka; Egner, Tobias
2012-01-01
Emotional arousal at encoding is known to facilitate later memory recall. In the present study, we asked whether this emotion-modulation of episodic memory is also evident at very short time scales, as measured by “feature integration effects,” the moment-by-moment binding of relevant stimulus and response features in episodic memory. This question was motivated by recent findings that negative emotion appears to potentiate first-order trial sequence effects in classic conflict tasks, which has been attributed to emotion-modulation of conflict-driven cognitive control processes. However, these effects could equally well have been carried by emotion-modulation of mnemonic feature binding processes, which were perfectly confounded with putative control processes in these studies. In the present experiments, we tried to shed light on this question by testing explicitly whether feature integration processes, assessed in isolation of conflict–control, are in fact susceptible to negative emotion-modulation. For this purpose, we adopted a standard protocol for assessing the rapid binding of stimulus and response features in episodic memory (Experiment 1) and paired it with the presentation of either neutral or fearful background face stimuli, shown either at encoding only (Experiment 2), or at both encoding and retrieval (Experiment 3). Whereas reliable feature integration effects were observed in all three experiments, no evidence for emotion-modulation of these effects was detected, in spite of significant effects of emotion on response times. These findings suggest that rapid feature integration of foreground stimulus and response features is not subject to modulation by negative emotional background stimuli and further suggest that previous reports of emotion-modulated trial–transition effects are likely attributable to the effects of emotion on cognitive control processes. PMID:22509172
Modulation of C. elegans Touch Sensitivity Is Integrated at Multiple Levels
Chen, Xiaoyin
2014-01-01
Sensory systems can adapt to different environmental signals. Here we identify four conditions that modulate anterior touch sensitivity in Caenorhabditis elegans after several hours and demonstrate that such sensory modulation is integrated at multiple levels to produce a single output. Prolonged vibration involving integrin signaling directly sensitizes the touch receptor neurons (TRNs). In contrast, hypoxia, the dauer state, and high salt reduce touch sensitivity by preventing the release of long-range neuroregulators, including two insulin-like proteins. Integration of these latter inputs occurs at upstream neurohormonal cells and at the insulin signaling cascade within the TRNs. These signals and those from integrin signaling converge to modulate touch sensitivity by regulating AKT kinases and DAF-16/FOXO. Thus, activation of either the integrin or insulin pathways can compensate for defects in the other pathway. This modulatory system integrates conflicting signals from different modalities, and adapts touch sensitivity to both mechanical and non-mechanical conditions. PMID:24806678
IAC - INTEGRATED ANALYSIS CAPABILITY
NASA Technical Reports Server (NTRS)
Frisch, H. P.
1994-01-01
The objective of the Integrated Analysis Capability (IAC) system is to provide a highly effective, interactive analysis tool for the integrated design of large structures. With the goal of supporting the unique needs of engineering analysis groups concerned with interdisciplinary problems, IAC was developed to interface programs from the fields of structures, thermodynamics, controls, and system dynamics with an executive system and database to yield a highly efficient multi-disciplinary system. Special attention is given to user requirements such as data handling and on-line assistance with operational features, and the ability to add new modules of the user's choice at a future date. IAC contains an executive system, a data base, general utilities, interfaces to various engineering programs, and a framework for building interfaces to other programs. IAC has shown itself to be effective in automatic data transfer among analysis programs. IAC 2.5, designed to be compatible as far as possible with Level 1.5, contains a major upgrade in executive and database management system capabilities, and includes interfaces to enable thermal, structures, optics, and control interaction dynamics analysis. The IAC system architecture is modular in design. 1) The executive module contains an input command processor, an extensive data management system, and driver code to execute the application modules. 2) Technical modules provide standalone computational capability as well as support for various solution paths or coupled analyses. 3) Graphics and model generation interfaces are supplied for building and viewing models. Advanced graphics capabilities are provided within particular analysis modules such as INCA and NASTRAN. 4) Interface modules provide for the required data flow between IAC and other modules. 5) User modules can be arbitrary executable programs or JCL procedures with no pre-defined relationship to IAC. 6) Special purpose modules are included, such as MIMIC (Model Integration via Mesh Interpolation Coefficients), which transforms field values from one model to another; LINK, which simplifies incorporation of user specific modules into IAC modules; and DATAPAC, the National Bureau of Standards statistical analysis package. The IAC database contains structured files which provide a common basis for communication between modules and the executive system, and can contain unstructured files such as NASTRAN checkpoint files, DISCOS plot files, object code, etc. The user can define groups of data and relations between them. A full data manipulation and query system operates with the database. The current interface modules comprise five groups: 1) Structural analysis - IAC contains a NASTRAN interface for standalone analysis or certain structural/control/thermal combinations. IAC provides enhanced structural capabilities for normal modes and static deformation analysis via special DMAP sequences. IAC 2.5 contains several specialized interfaces from NASTRAN in support of multidisciplinary analysis. 2) Thermal analysis - IAC supports finite element and finite difference techniques for steady state or transient analysis. There are interfaces for the NASTRAN thermal analyzer, SINDA/SINFLO, and TRASYS II. FEMNET, which converts finite element structural analysis models to finite difference thermal analysis models, is also interfaced with the IAC database. 3) System dynamics - The DISCOS simulation program which allows for either nonlinear time domain analysis or linear frequency domain analysis, is fully interfaced to the IAC database management capability. 4) Control analysis - Interfaces for the ORACLS, SAMSAN, NBOD2, and INCA programs allow a wide range of control system analyses and synthesis techniques. Level 2.5 includes EIGEN, which provides tools for large order system eigenanalysis, and BOPACE, which allows for geometric capabilities and finite element analysis with nonlinear material. Also included in IAC level 2.5 is SAMSAN 3.1, an engineering analysis program which contains a general purpose library of over 600 subroutin
Zhu, Ning Hua; Zhang, Hong Guang; Man, Jiang Wei; Zhu, Hong Liang; Ke, Jian Hong; Liu, Yu; Wang, Xin; Yuan, Hai Qing; Xie, Liang; Wang, Wei
2009-11-23
This paper presents a new technique to generate microwave signal using an electro-absorption modulator (EAM) integrated with a distributed feedback (DFB) laser subject to optical injection. Experiments show that the frequency of the generated microwave can be tuned by changing the wavelength of the external laser or adjusting the bias voltage of the EAM. The frequency response of the EAM is studied and found to be unsmooth due to packaging parasitic effects and four-wave mixing effect occurring in the active layer of the DFB laser. It is also demonstrated that an EA modulator integrated in between two DFB lasers can be used instead of the EML under optical injection. This integrated chip can be used to realize a monolithically integrated tunable microwave source.
NASA Technical Reports Server (NTRS)
Ankenman, Bruce; Ermer, Donald; Clum, James A.
1994-01-01
Modules dealing with statistical experimental design (SED), process modeling and improvement, and response surface methods have been developed and tested in two laboratory courses. One course was a manufacturing processes course in Mechanical Engineering and the other course was a materials processing course in Materials Science and Engineering. Each module is used as an 'experiment' in the course with the intent that subsequent course experiments will use SED methods for analysis and interpretation of data. Evaluation of the modules' effectiveness has been done by both survey questionnaires and inclusion of the module methodology in course examination questions. Results of the evaluation have been very positive. Those evaluation results and details of the modules' content and implementation are presented. The modules represent an important component for updating laboratory instruction and to provide training in quality for improved engineering practice.
SU-E-T-671: Range-Modulation Effects of Carbon Ion Beams in Lung Tissue
DOE Office of Scientific and Technical Information (OSTI.GOV)
Witt, M; Weber, U; Simeonov, Y
Purpose: When particles traversing inhomogeneous materials like lung they show a characteristic range modulation which cannot be observed in homogeneous materials. It is possible to describe the range modulation by a convolution of an unperturbed Bragg-Curve and a normal distribution. The sigma of the normal distribution is a parameter for the strength of the modulation effect. A new material parameter (modulation power, P-mod) is introduced which is independent of the material thickness. It is defined as the square of sigma divided by the mean water equivalent thickness of the target (µ). Methods: The modulation power of lung tissue was determinedmore » by actual Bragg-peak measurements after traversing an ex-vivo porcine lung and by Monte-Carlo simulations with micro-CT data of human lung tissue. The determined modulation powers were used to show the effect of range modulation effects in a simplified treatment situation. A four centimeter spread-out Bragg-peak after traversing eight centimeter of lung tissue was simulated in FLUKA. The SOBP with and without consideration of range modulation effects were compared. Results: As well in the measurements as in the MC simulations range modulation effects of lung tissue were observed. The determined modulation powers showed a great range from 0.05 mm, in the micro-CT data, to 0.7 mm in the lung measurements. The SOBP comparison showed that range modulation effects Result in over- and underdosages at the distal and proximal edge of the SOBP. In the investigated case, the last 0.5 cm of the SOBP showed an underdosage of up to 50% at the distal edge, while 0.5 cm distal to the SOBP an overdosage of up to 50% was observed. Conclusion: Range modulation effects occur in inhomogeneous materials like lung. These modulation effects may Result in clinically relevant over- and underdosages but are currently not considered in commercially available treatment planning systems.« less
Ruan, Yinlan; Ding, Liyun; Duan, Jingjing; Ebendorff-Heidepriem, Heike; Monro, Tanya M
2016-02-22
Integration of conductive materials into optical fibres can largely expand functions of fibre devices including surface plasmon resonator/metamaterial, modulators/detectors, or biosensors. Some early attempts have been made to incorporate metals such as tin into fibres during the fibre drawing process. Due to the restricted range of materials that have compatible melting temperatures with that of silica glass, the methods to incorporate metals along the length of the fibres are very challenging. Moreover, metals are nontransparent with strong light absorption, which causes high fibre loss. This article demonstrates a novel but simple method for creating transparent conductive reduced graphene oxide film onto microstructured silica fibres for potential optoelectronic applications. The strongly confined evanescent field of the suspended core fibres with only 2 μW average power was creatively used to transform graphene oxide into reduced graphene oxide with negligible additional loss. Existence of reduced graphene oxide was confirmed by their characteristic Raman signals, shifting of their fluorescence peaks as well as largely decreased resistance of the bulk GO film after laser beam exposure.
Active-learning assignments to integrate basic science and clinical course material.
Marshall, Leisa L; Nykamp, Diane
2010-09-10
To develop, implement, and evaluate active-learning exercises requiring the integration and application of pathophysiology, medicinal chemistry, pharmacology, and therapeutics knowledge of osteoarthritis and rheumatoid arthritis to formulate therapeutic recommendations for patients with musculoskeletal disorders. Two team-based case study exercises, one evaluating a patient with osteoarthritis and the second, a patient with rheumatoid arthritis, were developed, incorporating material and questions from pathophysiology, medicinal chemistry, pharmacology, and therapeutics. The learning assignments were implemented in a required pharmacotherapy module. Student learning was evaluated using performance on the team-based case study exercises and on 2 examinations. A standard student course evaluation was used to assess students' impressions of the learning activity. The mean student grades for the osteoarthritis and rheumatoid arthritis activities were 9.1 and 8.9, respectively, on a 10-point scale. The majority of students indicated that the learning exercises were more than adequate to excellent in helping students learn. The addition of active-learning activities was successful in teaching pharmacy students the knowledge needed to formulate therapeutic recommendations for patients with musculoskeletal disorders.
Real-time and accelerated outdoor endurance testing of solar cells
NASA Technical Reports Server (NTRS)
Forestieri, A. F.; Anagnostou, E.
1978-01-01
Materials for solar-cell module construction have been studied on the basis of limited real-time outdoor exposure evaluations. The materials tested included transmission samples, sub-modules, and actual solar cells. The results suggest that glass, fluorinated ethylene propylene, and perfluoroalkoxy are good materials for the covering or encapsulation of solar-cell modules. In all cases, dirt accumulation and cleanability are important factors.
An employee sews thermal insulation material on the front heat shield of the Huygens probe in the PH
NASA Technical Reports Server (NTRS)
1997-01-01
An employee in the Payload Hazardous Servicing Facility (PHSF) sews thermal insulation material on the front heat shield of the Huygens probe during prelaunch processing testing and integration in that facility, with the probe's back cover in the background. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.
An employee sews thermal insulation material on the back cover and heat shield of the Huygens probe
NASA Technical Reports Server (NTRS)
1997-01-01
An employee in the Payload Hazardous Servicing Facility (PHSF) sews thermal insulation material on the back cover and heat shield of the Huygens probe during prelaunch processing, testing and integration in that facility. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.
Module-based multiscale simulation of angiogenesis in skeletal muscle
2011-01-01
Background Mathematical modeling of angiogenesis has been gaining momentum as a means to shed new light on the biological complexity underlying blood vessel growth. A variety of computational models have been developed, each focusing on different aspects of the angiogenesis process and occurring at different biological scales, ranging from the molecular to the tissue levels. Integration of models at different scales is a challenging and currently unsolved problem. Results We present an object-oriented module-based computational integration strategy to build a multiscale model of angiogenesis that links currently available models. As an example case, we use this approach to integrate modules representing microvascular blood flow, oxygen transport, vascular endothelial growth factor transport and endothelial cell behavior (sensing, migration and proliferation). Modeling methodologies in these modules include algebraic equations, partial differential equations and agent-based models with complex logical rules. We apply this integrated model to simulate exercise-induced angiogenesis in skeletal muscle. The simulation results compare capillary growth patterns between different exercise conditions for a single bout of exercise. Results demonstrate how the computational infrastructure can effectively integrate multiple modules by coordinating their connectivity and data exchange. Model parameterization offers simulation flexibility and a platform for performing sensitivity analysis. Conclusions This systems biology strategy can be applied to larger scale integration of computational models of angiogenesis in skeletal muscle, or other complex processes in other tissues under physiological and pathological conditions. PMID:21463529
Integrated circuits, and design and manufacture thereof
Auracher, Stefan; Pribbernow, Claus; Hils, Andreas
2006-04-18
A representation of a macro for an integrated circuit layout. The representation may define sub-circuit cells of a module. The module may have a predefined functionality. The sub-circuit cells may include at least one reusable circuit cell. The reusable circuit cell may be configured such that when the predefined functionality of the module is not used, the reusable circuit cell is available for re-use.
ERIC Educational Resources Information Center
Chief of Naval Education and Training Support, Pensacola, FL.
This individualized learning module on linear integrated circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Two lessons are included in…
Lin, Fang-Zheng; Wu, Tsu-Hsiu; Chiu, Yi-Jen
2009-06-08
A new monolithic integration scheme, namely cascaded-integration (CI), for improving high-speed optical modulation is proposed and demonstrated. High-speed electroabsorption modulators (EAMs) and semiconductor optical amplifiers (SOAs) are taken as the integrated elements of CI. This structure is based on an optical waveguide defined by cascading segmented EAMs with segmented SOAs, while high-impedance transmission lines (HITLs) are used for periodically interconnecting EAMs, forming a distributive optical re-amplification and re-modulation. Therefore, not only the optical modulation can be beneficial from SOA gain, but also high electrical reflection due to EAM low characteristic impedance can be greatly reduced. Two integration schemes, CI and conventional single-section (SS), with same total EAM- and SOA- lengths are fabricated and compared to examine the concept. Same modulation-depth against with EAM bias (up to 5V) as well as SOA injection current (up to 60mA) is found in both structures. In comparison with SS, a < 1dB extra optical-propagation loss in CI is measured due to multi-sections of electrical-isolation regions between EAMs and SOAs, suggesting no significant deterioration in CI on DC optical modulation efficiency. Lower than -12dB of electrical reflection from D.C. to 30GHz is observed in CI, better than -5dB reflection in SS for frequency of above 5GHz. Superior high-speed electrical properties in CI structure can thus lead to higher speed of electrical-to-optical (EO) response, where -3dB bandwidths are >30GHz and 13GHz for CI and SS respectively. Simulation results on electrical and EO response are quite consistent with measurement, confirming that CI can lower the driving power at high-speed regime, while the optical loss is still kept the same level. Taking such distributive advantage (CI) with optical gain, not only higher-speed modulation with high output optical power can be attained, but also the trade-off issue due to impedance mismatch can be released to reduce the driving power of modulator. Such kind of monolithic integration scheme also has potential for the applications of other high-speed optoelectronics devices.
Electric-field-controlled interface dipole modulation for Si-based memory devices.
Miyata, Noriyuki
2018-05-31
Various nonvolatile memory devices have been investigated to replace Si-based flash memories or emulate synaptic plasticity for next-generation neuromorphic computing. A crucial criterion to achieve low-cost high-density memory chips is material compatibility with conventional Si technologies. In this paper, we propose and demonstrate a new memory concept, interface dipole modulation (IDM) memory. IDM can be integrated as a Si field-effect transistor (FET) based memory device. The first demonstration of this concept employed a HfO 2 /Si MOS capacitor where the interface monolayer (ML) TiO 2 functions as a dipole modulator. However, this configuration is unsuitable for Si-FET-based devices due to its large interface state density (D it ). Consequently, we propose, a multi-stacked amorphous HfO 2 /1-ML TiO 2 /SiO 2 IDM structure to realize a low D it and a wide memory window. Herein we describe the quasi-static and pulse response characteristics of multi-stacked IDM MOS capacitors and demonstrate flash-type and analog memory operations of an IDM FET device.
Development of probabilistic multimedia multipathway computer codes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, C.; LePoire, D.; Gnanapragasam, E.
2002-01-01
The deterministic multimedia dose/risk assessment codes RESRAD and RESRAD-BUILD have been widely used for many years for evaluation of sites contaminated with residual radioactive materials. The RESRAD code applies to the cleanup of sites (soils) and the RESRAD-BUILD code applies to the cleanup of buildings and structures. This work describes the procedure used to enhance the deterministic RESRAD and RESRAD-BUILD codes for probabilistic dose analysis. A six-step procedure was used in developing default parameter distributions and the probabilistic analysis modules. These six steps include (1) listing and categorizing parameters; (2) ranking parameters; (3) developing parameter distributions; (4) testing parameter distributionsmore » for probabilistic analysis; (5) developing probabilistic software modules; and (6) testing probabilistic modules and integrated codes. The procedures used can be applied to the development of other multimedia probabilistic codes. The probabilistic versions of RESRAD and RESRAD-BUILD codes provide tools for studying the uncertainty in dose assessment caused by uncertain input parameters. The parameter distribution data collected in this work can also be applied to other multimedia assessment tasks and multimedia computer codes.« less
Thermal expansion of vitrified blood vessels permeated with DP6 and synthetic ice modulators.
Eisenberg, David P; Taylor, Michael J; Jimenez-Rios, Jorge L; Rabin, Yoed
2014-06-01
This study provides thermal expansion data for blood vessels permeated with the cryoprotective cocktail DP6, when combined with selected synthetic ice modulators (SIMs): 12% polyethylene glycol 400, 6% 1,3-cyclohexanediol, and 6% 2,3-butanediol. The general classification of SIMs includes molecules that modulate ice nucleation and growth, or possess properties of stabilizing the amorphous state, by virtue of their chemical structure and at concentrations that are not explained on a purely colligative basis. The current study is part of an ongoing effort to characterize thermo-mechanical effects on structural integrity of cryopreserved materials, where thermal expansion is the driving mechanism to thermo-mechanical stress. This study focuses on the lower part of the cryogenic temperature range, where the cryoprotective agent (CPA) behaves as a solid for all practical applications. By combining results obtained in the current study with literature data on the thermal expansion in the upper part of the cryogenic temperature range, unified thermal expansion curves are presented. Copyright © 2014 Elsevier Inc. All rights reserved.
Exciton Emission Intensity Modulation of Monolayer MoS2 via Au Plasmon Coupling
Mukherjee, B.; Kaushik, N.; Tripathi, Ravi P. N.; Joseph, A. M.; Mohapatra, P. K.; Dhar, S.; Singh, B. P.; Kumar, G. V. Pavan; Simsek, E.; Lodha, S.
2017-01-01
Modulation of photoluminescence of atomically thin transition metal dichalcogenide two-dimensional materials is critical for their integration in optoelectronic and photonic device applications. By coupling with different plasmonic array geometries, we have shown that the photoluminescence intensity can be enhanced and quenched in comparison with pristine monolayer MoS2. The enhanced exciton emission intensity can be further tuned by varying the angle of polarized incident excitation. Through controlled variation of the structural parameters of the plasmonic array in our experiment, we demonstrate modulation of the photoluminescence intensity from nearly fourfold quenching to approximately threefold enhancement. Our data indicates that the plasmonic resonance couples to optical fields at both, excitation and emission bands, and increases the spontaneous emission rate in a double spacing plasmonic array structure as compared with an equal spacing array structure. Furthermore our experimental results are supported by numerical as well as full electromagnetic wave simulations. This study can facilitate the incorporation of plasmon-enhanced transition metal dichalcogenide structures in photodetector, sensor and light emitter applications. PMID:28134260
Park, Jin-Kown; Takagi, Shinichi; Takenaka, Mitsuru
2018-02-19
We demonstrated the monolithic integration of a carrier-injection InGaAsP Mach-Zehnder interferometer (MZI) optical modulator and InGaAs metal-oxide-semiconductor field-effect transistor (MOSFET) on a III-V-on-insulator (III-V-OI) wafer. A low-resistivity lateral PIN junction was formed along an InGaAsP rib waveguide by Zn diffusion and Ni-InGaAsP alloy, enabling direct driving of the InGaAsP optical modulator by the InGaAs MOSFET. A π phase shift of the InGaAsP optical modulator was obtained through the injection of a drain current from the InGaAs MOSFET with a gate voltage of approximately 1 V. This proof-of-concept demonstration of the monolithic integration of the InGaAsP optical modulator and InGaAs driver MOSFET will enable us to develop high-performance and low-power electronic-photonic integrated circuits on a III-V CMOS photonics platform.
NASA Technical Reports Server (NTRS)
Packard, Edward A.
2004-01-01
This viewgraph presentation provides information on the design, construction, and operation of a cryogenic chamber, and its use in testing the Integrated Science Instrument Module (ISIM) for the James Webb Space Telescope (JWST).
Submillimeter-Wave Amplifier Module with Integrated Waveguide Transitions
NASA Technical Reports Server (NTRS)
Samoska, Lorene; Chattopadhyay, Goutam; Pukala, David; Gaier, Todd; Soria, Mary; ManFung, King; Deal, William; Mei, Gerry; Radisic, Vesna; Lai, Richard
2009-01-01
To increase the usefulness of monolithic millimeter-wave integrated circuit (MMIC) components at submillimeter-wave frequencies, a chip has been designed that incorporates two integrated, radial E-plane probes with an MMIC amplifier in between, thus creating a fully integrated waveguide module. The integrated amplifier chip has been fabricated in 35-nm gate length InP high-electron-mobility-transistor (HEMT) technology. The radial probes were mated to grounded coplanar waveguide input and output lines in the internal amplifier. The total length of the internal HEMT amplifier is 550 m, while the total integrated chip length is 1,085 m. The chip thickness is 50 m with the chip width being 320 m. The internal MMIC amplifier is biased through wire-bond connections to the gates and drains of the chip. The chip has 3 stages, employing 35-nm gate length transistors in each stage. Wire bonds from the DC drain and gate pads are connected to off-chip shunt 51-pF capacitors, and additional off-chip capacitors and resistors are added to the gate and drain bias lines for low-frequency stability of the amplifier. Additionally, bond wires to the grounded coplanar waveguide pads at the RF input and output of the internal amplifier are added to ensure good ground connections to the waveguide package. The S-parameters of the module, not corrected for input or output waveguide loss, are measured at the waveguide flange edges. The amplifier module has over 10 dB of gain from 290 to 330 GHz, with a peak gain of over 14 dB at 307 GHz. The WR2.2 waveguide cutoff is again observed at 268 GHz. The module is biased at a drain current of 27 mA, a drain voltage of 1.24 V, and a gate voltage of +0.21 V. Return loss of the module is very good between 5 to 25 dB. This result illustrates the usefulness of the integrated radial probe transition, and the wide (over 10-percent) bandwidth that one can expect for amplifier modules with integrated radial probes in the submillimeter-regime (>300 GHz).
Liu, Juan; Ando, Hiroshi
2016-01-01
Most real-world events stimulate multiple sensory modalities simultaneously. Usually, the stiffness of an object is perceived haptically. However, auditory signals also contain stiffness-related information, and people can form impressions of stiffness from the different impact sounds of metal, wood, or glass. To understand whether there is any interaction between auditory and haptic stiffness perception, and if so, whether the inferred material category is the most relevant auditory information, we conducted experiments using a force-feedback device and the modal synthesis method to present haptic stimuli and impact sound in accordance with participants’ actions, and to modulate low-level acoustic parameters, i.e., frequency and damping, without changing the inferred material categories of sound sources. We found that metal sounds consistently induced an impression of stiffer surfaces than did drum sounds in the audio-only condition, but participants haptically perceived surfaces with modulated metal sounds as significantly softer than the same surfaces with modulated drum sounds, which directly opposes the impression induced by these sounds alone. This result indicates that, although the inferred material category is strongly associated with audio-only stiffness perception, low-level acoustic parameters, especially damping, are more tightly integrated with haptic signals than the material category is. Frequency played an important role in both audio-only and audio-haptic conditions. Our study provides evidence that auditory information influences stiffness perception differently in unisensory and multisensory tasks. Furthermore, the data demonstrated that sounds with higher frequency and/or shorter decay time tended to be judged as stiffer, and contact sounds of stiff objects had no effect on the haptic perception of soft surfaces. We argue that the intrinsic physical relationship between object stiffness and acoustic parameters may be applied as prior knowledge to achieve robust estimation of stiffness in multisensory perception. PMID:27902718
An integrated theory of the mind.
Anderson, John R; Bothell, Daniel; Byrne, Michael D; Douglass, Scott; Lebiere, Christian; Qin, Yulin
2004-10-01
Adaptive control of thought-rational (ACT-R; J. R. Anderson & C. Lebiere, 1998) has evolved into a theory that consists of multiple modules but also explains how these modules are integrated to produce coherent cognition. The perceptual-motor modules, the goal module, and the declarative memory module are presented as examples of specialized systems in ACT-R. These modules are associated with distinct cortical regions. These modules place chunks in buffers where they can be detected by a production system that responds to patterns of information in the buffers. At any point in time, a single production rule is selected to respond to the current pattern. Subsymbolic processes serve to guide the selection of rules to fire as well as the internal operations of some modules. Much of learning involves tuning of these subsymbolic processes. A number of simple and complex empirical examples are described to illustrate how these modules function singly and in concert. 2004 APA
Enhanced all-optical modulation in a graphene-coated fibre with low insertion loss
Zhang, Haojie; Healy, Noel; Shen, Li; Huang, Chung Che; Hewak, Daniel W.; Peacock, Anna C.
2016-01-01
Graphene is a highly versatile two-dimensional material platform that offers exceptional optical and electrical properties. Of these, its dynamic conductivity and low effective carrier mass are of particular interest for optoelectronic applications as they underpin the material’s broadband nonlinear optical absorption and ultra-fast carrier mobility, respectively. In this paper, we utilize these phenomena to demonstrate a high-speed, in-fibre optical modulator developed on a side-polished optical fibre platform. An especially low insertion loss (<1 dB) was achieved by polishing the fibre to a near atomically smooth surface (<1 nm RMS), which minimized scattering and ensured excellent contact between the graphene film and the fibre. In order to enhance the light-matter interaction, the graphene film is coated with a high index polyvinyl butyral layer, which has the added advantage of acting as a barrier to the surrounding environment. Using this innovative approach, we have fabricated a robust and stable all-fibre device with an extinction ratio as high as 9 dB and operation bandwidth of 0.5 THz. These results represent a key step towards the integration of low-dimensional materials within standard telecoms networks. PMID:27001353
Knight, Jonathan D; Fulop, Rebecca M; Márquez-Magaña, Leticia; Tanner, Kimberly D
2008-01-01
Active-learning strategies are increasingly being integrated into college-level science courses to make material more accessible to all students and to improve learning outcomes. One active-learning pedagogy, case-based learning (CBL), was developed as a way to both enhance engagement in the material and to accommodate diverse learning styles. Yet, adoption of CBL approaches in undergraduate biology courses has been piecemeal, in part because of the perceived investment of time required. Furthermore, few CBL lesson plans have been developed specifically for upper-division laboratory courses. Here, we describe four cases that we developed and implemented for a senior cell and molecular biology laboratory course at San Francisco State University, a minority-serving institution. To evaluate the effectiveness of these modules, we used both written and verbal assessments to gauge learning outcomes and attitudinal responses of students over two semesters. Students responded positively to the new approach and seemed to meet the learning goals for the course. Most said they would take a course using CBL again. These case modules are readily adaptable to a variety of classroom settings.
Fulop, Rebecca M.; Márquez-Magaña, Leticia; Tanner, Kimberly D.
2008-01-01
Active-learning strategies are increasingly being integrated into college-level science courses to make material more accessible to all students and to improve learning outcomes. One active-learning pedagogy, case-based learning (CBL), was developed as a way to both enhance engagement in the material and to accommodate diverse learning styles. Yet, adoption of CBL approaches in undergraduate biology courses has been piecemeal, in part because of the perceived investment of time required. Furthermore, few CBL lesson plans have been developed specifically for upper-division laboratory courses. Here, we describe four cases that we developed and implemented for a senior cell and molecular biology laboratory course at San Francisco State University, a minority-serving institution. To evaluate the effectiveness of these modules, we used both written and verbal assessments to gauge learning outcomes and attitudinal responses of students over two semesters. Students responded positively to the new approach and seemed to meet the learning goals for the course. Most said they would take a course using CBL again. These case modules are readily adaptable to a variety of classroom settings. PMID:19047425
Deployable bamboo structure project: A building life-cycle report
NASA Astrophysics Data System (ADS)
Firdaus, Adrian; Prastyatama, Budianastas; Sagara, Altho; Wirabuana, Revian N.
2017-11-01
Bamboo is considered as a sustainable material in the world of construction, and it is vastly available in Indonesia. The general utilization of the material is increasingly frequent, however, its usage as a deployable structure-a recently-developed use of bamboo, is still untapped. This paper presents a report on a deployable bamboo structure project, covering the entire building life-cycle phase. The cycle encompasses the designing; fabrication; transportation; construction; operation and maintenance; as well as a plan for future re-use. The building is made of a configuration of the structural module, each being a folding set of bars which could be reduced in size to fit into vehicles for easy transportation. Each structural module was made of Gigantochloa apus bamboo. The fabrication, transportation, and construction phase require by a minimum of three workers. The fabrication and construction phase require three hours and fifteen minutes respectively. The building is utilized as cafeteria stands, the operation and maintenance phase started since early March 2017. The maintenance plan is scheduled on a monthly basis, focusing on the inspection of the locking mechanism element and the entire structural integrity. The building is designed to allow disassembly process so that it is reusable in the future.
Naver: a PC-cluster-based VR system
NASA Astrophysics Data System (ADS)
Park, ChangHoon; Ko, HeeDong; Kim, TaiYun
2003-04-01
In this paper, we present a new framework NAVER for virtual reality application. The NAVER is based on a cluster of low-cost personal computers. The goal of NAVER is to provide flexible, extensible, scalable and re-configurable framework for the virtual environments defined as the integration of 3D virtual space and external modules. External modules are various input or output devices and applications on the remote hosts. From the view of system, personal computers are divided into three servers according to its specific functions: Render Server, Device Server and Control Server. While Device Server contains external modules requiring event-based communication for the integration, Control Server contains external modules requiring synchronous communication every frame. And, the Render Server consists of 5 managers: Scenario Manager, Event Manager, Command Manager, Interaction Manager and Sync Manager. These managers support the declaration and operation of virtual environment and the integration with external modules on remote servers.
van Erp, Nicole H J; van Vugt, Maaike; Verhoeven, Dorien; Kroon, Hans
2009-01-01
This brief report addresses the systematic implementation of skills training modules for persons with schizophrenia or related disorders in three Dutch mental health agencies. Information on barriers, strategies and integration into routine daily practice was gathered at 0, 12 and 24 months through interviews with managers, program leaders, trainers, practitioners and clients. Overall implementation of the skills training modules for 74% of the persons with schizophrenia or related disorders was not feasible. Implementation was impeded by an incapable program leader, organizational changes, disappointing referrals and loss of trainers. The agencies made important steps forward to integrate the modules into routine daily practice. A reach percentage of 74% in two years time is too ambitious and needs to be adjusted. Systematic integration of the modules into routine daily practice is feasible, but requires solid program management and continuous effort to involve clients and practitioners.
Effectiveness of integrated teaching module in pharmacology among medical undergraduates.
Yadav, Preeti P; Chaudhary, Mayur; Patel, Jayshree; Shah, Aashal; Kantharia, N D
2016-01-01
Over the years with advancement of science and technology, each subject has become highly specialized. Teaching of medical students has still remained separate in various departments with no scope of integration in majority of medical institutes in India. Study was planned to have an experience of integration in institute and sensitize faculty for integrated teaching-learning (TL) method. To prepare and test effectiveness of integrated teaching module for 2(nd) year MBBS student in pharmacology and to sensitize and motivate faculties toward advantages of implementing integrated module. Education intervention project implemented 2(nd) year MBBS students of Government Medical College and New Civil Hospital, Surat. Students of second MBBS were divided into two groups. One group was exposed to integrated teaching sessions and another to traditional method. Both the groups were assessed by pre- and post-test questionnaire, feedback and focus group discussions were conducted to know their experience about process. A total of 165 students of the 2(nd) year MBBS were exposed to the integrated teaching module for two topics in two groups. One group was taught by traditional teaching, and another group was exposed to the integrated TL session. Both the groups have shown a significant improvement in posttest scores but increase in mean score was more in integrated group. During analysis of feedback forms, it was noted that students preferred integrated TL methods since they help in better understanding. Faculty feedback shows consensus over the adaptation of integrated TL methods. Integrated TL sessions were well-appreciated by students and faculties. To improve the critical reasoning skills and self-directed learning of students, integrated TL is highly recommended for must know areas of curriculum.
Guo, Peijun; Weimer, Matthew S; Emery, Jonathan D; Diroll, Benjamin T; Chen, Xinqi; Hock, Adam S; Chang, Robert P H; Martinson, Alex B F; Schaller, Richard D
2017-01-24
Actively tunable optical transmission through artificial metamaterials holds great promise for next-generation nanophotonic devices and metasurfaces. Plasmonic nanostructures and phase change materials have been extensively studied to this end due to their respective strong interactions with light and tunable dielectric constants under external stimuli. Seamlessly integrating plasmonic components with phase change materials, as demonstrated in the present work, can facilitate phase change by plasmonically enabled light confinement and meanwhile make use of the high sensitivity of plasmon resonances to the variation of dielectric constant associated with the phase change. The hybrid platform here is composed of plasmonic indium-tin-oxide nanorod arrays (ITO-NRAs) conformally coated with an ultrathin layer of a prototypical phase change material, vanadium dioxide (VO 2 ), which enables all-optical modulation of the infrared as well as the visible spectral ranges. The interplay between the intrinsic plasmonic nonlinearity of ITO-NRAs and the phase transition induced permittivity change of VO 2 gives rise to spectral and temporal responses that cannot be achieved with individual material components alone.
First Materials Science Research Facility Rack Capabilities and Design Features
NASA Technical Reports Server (NTRS)
Cobb, S.; Higgins, D.; Kitchens, L.; Curreri, Peter (Technical Monitor)
2002-01-01
The first Materials Science Research Rack (MSRR-1) is the primary facility for U.S. sponsored materials science research on the International Space Station. MSRR-1 is contained in an International Standard Payload Rack (ISPR) equipped with the Active Rack Isolation System (ARIS) for the best possible microgravity environment. MSRR-1 will accommodate dual Experiment Modules and provide simultaneous on-orbit processing operations capability. The first Experiment Module for the MSRR-1, the Materials Science Laboratory (MSL), is an international cooperative activity between NASA's Marshall Space Flight Center (MSFC) and the European Space Agency's (ESA) European Space Research and Technology Center (ESTEC). The MSL Experiment Module will accommodate several on-orbit exchangeable experiment-specific Module Inserts which provide distinct thermal processing capabilities. Module Inserts currently planned for the MSL are a Quench Module Insert, Low Gradient Furnace, and a Solidification with Quench Furnace. The second Experiment Module for the MSRR-1 configuration is a commercial device supplied by MSFC's Space Products Development (SPD) Group. Transparent furnace assemblies include capabilities for vapor transport processes and annealing of glass fiber preforms. This Experiment Module is replaceable on-orbit. This paper will describe facility capabilities, schedule to flight and research opportunities.
All optical controlled photonic integrated circuits using azo dye functionized sol-gel material
NASA Astrophysics Data System (ADS)
Ke, Xianjun
The main focus of this dissertation is development and characterization of all-optical controllable azo dye functionized sol gel material, demonstrating a PIC fabrication technique on glass substrate using such material, and exploration and feasibility demonstration of three PIC functional devices namely optical variable attenuator, optical switches, and optical tunable filters using the material. The realization of all the devices in this dissertation are based on one material: dye functionalized sol-gel material. A photochromic sol-gel material functionalized with azo dye was synthesized and characterized. It possesses a photochromic characteristic under the control of green laser beam illumination. The material characteristics suggest the possibility of a new promising material platform candidate for the fabrication of alloptical controlled photonic integrated circuits. As the first potential application of the dye functionalized sol-gel material, an alloptical variable attenuator was designed and demonstrated. The optical variable attenuation is achieved in Mach-Zehnder interferometric configuration through all-optical modulation of sol-gel waveguide phase shifters. A 2 x 2 optical switch based on multimode interference (MMI) waveguide structure is proposed in the dissertation. The schematic configuration of the optical switch consists of a cascade of two identical MMIs with two all-optical controlled phase shifters realized by using the photochromic sol-gel material. The cross or bar switch state of the optical switch is determined by the phase difference between the two sol-gel waveguide phase shifters. An all-optical tunable filter is designed and its feasibility demonstrated by using the sol-gel photochromic material. Except for the phase change demonstrated on sol-gel waveguide phase shifters, dynamic gratings were observed on sol-gel film when exposed to two interference beams. This reveals the possibility of realizing Bragg grating-based tunable filters. The schematic configuration of proposed tunable filters consists of a single straight waveguide embedded with a sol-gel waveguide. The wavelength tuning of the tunable filters is accomplished by varying the grating period.
Bratt-Leal, Andrés M.; Carpenedo, Richard L.; Ungrin, Mark; Zandstra, Peter W.; McDevitt, Todd C.
2010-01-01
Biomaterials are increasingly being used to engineer the biochemical and biophysical properties of the extracellular stem cell microenvironment in order to tailor niche characteristics and direct cell phenotype. To date, stem cell-biomaterial interactions have largely been studied by introducing stem cells into artificial environments, such as 2D cell culture on biomaterial surfaces, encapsulation of cell suspensions within hydrogel materials, or cell seeding on 3D polymeric scaffolds. In this study, microparticles fabricated from different materials, such as agarose, PLGA and gelatin, were stably integrated, in a dose-dependent manner, within aggregates of pluripotent stem cells (PSCs) prior to differentiation as a means to directly examine stem cell-biomaterial interactions in 3D. Interestingly, the presence of the materials within the stem cell aggregates differentially modulated the gene and protein expression patterns of several differentiation markers without adversely affecting cell viability. Microparticle incorporation within 3D stem cell aggregates can control the spatial presentation of extracellular environmental cues (i.e. soluble factors, extracellular matrix and intercellular adhesion molecules) as a means to direct the differentiation of stem cells for tissue engineering and regenerative medicine applications. In addition, these results suggest that the physical presence of microparticles within stem cell aggregates does not compromise PSC differentiation, but in fact the choice of biomaterials can impact the propensity of stem cells to adopt particular differentiated cell phenotypes. PMID:20864164
Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery
De Falco, Iris; Gerboni, Giada; Cianchetti, Matteo; Menciassi, Arianna
2015-01-01
In recent years, soft robotics technologies have aroused increasing interest in the medical field due to their intrinsically safe interaction in unstructured environments. At the same time, new procedures and techniques have been developed to reduce the invasiveness of surgical operations. Minimally Invasive Surgery (MIS) has been successfully employed for abdominal interventions, however standard MIS procedures are mainly based on rigid or semi-rigid tools that limit the dexterity of the clinician. This paper presents a soft and high dexterous manipulator for MIS. The manipulator was inspired by the biological capabilities of the octopus arm, and is designed with a modular approach. Each module presents the same functional characteristics, thus achieving high dexterity and versatility when more modules are integrated. The paper details the design, fabrication process and the materials necessary for the development of a single unit, which is fabricated by casting silicone inside specific molds. The result consists in an elastomeric cylinder including three flexible pneumatic actuators that enable elongation and omni-directional bending of the unit. An external braided sheath improves the motion of the module. In the center of each module a granular jamming-based mechanism varies the stiffness of the structure during the tasks. Tests demonstrate that the module is able to bend up to 120° and to elongate up to 66% of the initial length. The module generates a maximum force of 47 N, and its stiffness can increase up to 36%. PMID:26650236
Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery.
De Falco, Iris; Gerboni, Giada; Cianchetti, Matteo; Menciassi, Arianna
2015-11-14
In recent years, soft robotics technologies have aroused increasing interest in the medical field due to their intrinsically safe interaction in unstructured environments. At the same time, new procedures and techniques have been developed to reduce the invasiveness of surgical operations. Minimally Invasive Surgery (MIS) has been successfully employed for abdominal interventions, however standard MIS procedures are mainly based on rigid or semi-rigid tools that limit the dexterity of the clinician. This paper presents a soft and high dexterous manipulator for MIS. The manipulator was inspired by the biological capabilities of the octopus arm, and is designed with a modular approach. Each module presents the same functional characteristics, thus achieving high dexterity and versatility when more modules are integrated. The paper details the design, fabrication process and the materials necessary for the development of a single unit, which is fabricated by casting silicone inside specific molds. The result consists in an elastomeric cylinder including three flexible pneumatic actuators that enable elongation and omni-directional bending of the unit. An external braided sheath improves the motion of the module. In the center of each module a granular jamming-based mechanism varies the stiffness of the structure during the tasks. Tests demonstrate that the module is able to bend up to 120° and to elongate up to 66% of the initial length. The module generates a maximum force of 47 N, and its stiffness can increase up to 36%.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hector, Jr., Louis G.; McCarty, Eric D.
The goal of the ICME 3GAHSS project was to successfully demonstrate the applicability of Integrated Computational Materials Engineering (ICME) for the development and deployment of third generation advanced high strength steels (3GAHSS) for immediate weight reduction in passenger vehicles. The ICME approach integrated results from well-established computational and experimental methodologies to develop a suite of material constitutive models (deformation and failure), manufacturing process and performance simulation modules, a properties database, as well as the computational environment linking them together for both performance prediction and material optimization. This is the Final Report for the ICME 3GAHSS project, which achieved the fol-lowingmore » objectives: 1) Developed a 3GAHSS ICME model, which includes atomistic, crystal plasticity, state variable and forming models. The 3GAHSS model was implemented in commercially available LS-DYNA and a user guide was developed to facilitate use of the model. 2) Developed and produced two 3GAHSS alloys using two different chemistries and manufacturing processes, for use in calibrating and validating the 3GAHSS ICME Model. 3) Optimized the design of an automotive subassembly by substituting 3GAHSS for AHSS yielding a design that met or exceeded all baseline performance requirements with a 30% mass savings. A technical cost model was also developed to estimate the cost per pound of weight saved when substituting 3GAHSS for AHSS. The project demonstrated the potential for 3GAHSS to achieve up to 30% weight savings in an automotive structure at a cost penalty of up to $0.32 to $1.26 per pound of weight saved. The 3GAHSS ICME Model enables the user to design 3GAHSS to desired mechanical properties in terms of strength and ductility.« less
NASA Technical Reports Server (NTRS)
Liu, Nan-Suey
2001-01-01
A multi-disciplinary design/analysis tool for combustion systems is critical for optimizing the low-emission, high-performance combustor design process. Based on discussions between then NASA Lewis Research Center and the jet engine companies, an industry-government team was formed in early 1995 to develop the National Combustion Code (NCC), which is an integrated system of computer codes for the design and analysis of combustion systems. NCC has advanced features that address the need to meet designer's requirements such as "assured accuracy", "fast turnaround", and "acceptable cost". The NCC development team is comprised of Allison Engine Company (Allison), CFD Research Corporation (CFDRC), GE Aircraft Engines (GEAE), NASA Glenn Research Center (LeRC), and Pratt & Whitney (P&W). The "unstructured mesh" capability and "parallel computing" are fundamental features of NCC from its inception. The NCC system is composed of a set of "elements" which includes grid generator, main flow solver, turbulence module, turbulence and chemistry interaction module, chemistry module, spray module, radiation heat transfer module, data visualization module, and a post-processor for evaluating engine performance parameters. Each element may have contributions from several team members. Such a multi-source multi-element system needs to be integrated in a way that facilitates inter-module data communication, flexibility in module selection, and ease of integration. The development of the NCC beta version was essentially completed in June 1998. Technical details of the NCC elements are given in the Reference List. Elements such as the baseline flow solver, turbulence module, and the chemistry module, have been extensively validated; and their parallel performance on large-scale parallel systems has been evaluated and optimized. However the scalar PDF module and the Spray module, as well as their coupling with the baseline flow solver, were developed in a small-scale distributed computing environment. As a result, the validation of the NCC beta version as a whole was quite limited. Current effort has been focused on the validation of the integrated code and the evaluation/optimization of its overall performance on large-scale parallel systems.
Crunteanu, Aurelian; Givernaud, Julien; Leroy, Jonathan; Mardivirin, David; Champeaux, Corinne; Orlianges, Jean-Christophe; Catherinot, Alain; Blondy, Pierre
2010-12-01
Vanadium dioxide is an intensively studied material that undergoes a temperature-induced metal-insulator phase transition accompanied by a large change in electrical resistivity. Electrical switches based on this material show promising properties in terms of speed and broadband operation. The exploration of the failure behavior and reliability of such devices is very important in view of their integration in practical electronic circuits. We performed systematic lifetime investigations of two-terminal switches based on the electrical activation of the metal-insulator transition in VO 2 thin films. The devices were integrated in coplanar microwave waveguides (CPWs) in series configuration. We detected the evolution of a 10 GHz microwave signal transmitted through the CPW, modulated by the activation of the VO 2 switches in both voltage- and current-controlled modes. We demonstrated enhanced lifetime operation of current-controlled VO 2 -based switching (more than 260 million cycles without failure) compared with the voltage-activated mode (breakdown at around 16 million activation cycles). The evolution of the electrical self-oscillations of a VO 2 -based switch induced in the current-operated mode is a subtle indicator of the material properties modification and can be used to monitor its behavior under various external stresses in sensor applications.
Engineering Cell-Cell Signaling
Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R.
2014-01-01
Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling based on quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilizing synthetic cells, advanced ‘chassis’ and predictive modeling to engineer the form and function of living tissues. PMID:23856592
ERIC Educational Resources Information Center
New South Wales Dept. of Corrective Services, Sydney (Australia).
This document contains learning modules for adult basic education courses in Australia, along with teacher information for integrating curricula, using integrated themes, and planning curricula. The learning modules contain learning activities in the following areas: job search skills; occupational health and safety; life skills; ceramics;…
Nakagawa, Jun; Takahashi, Muneyoshi; Okada, Rieko; Matsushima, Eisuke; Matsuda, Tetsuya
2015-01-01
Men, like the male of many animal species, use gifts to build satisfactory relationships with a desired woman. From the woman's perspective, all gifts are not always equally rewarding; the reward value of a gift depends on two factors: (1) the giver and (2) the type of the gift (the gift's social meaning). In this study, we investigated how these two factors interactively determine the reward value of a gift. Specifically, we examined how the neural processing for understanding a gift's social meaning is modulated by preferences for the giver. We performed a functional magnetic resonance imaging (fMRI) study in which a female participant was asked to judge a gift from a male she was acquainted with in real life. We examined the interactive effects between (1) the female participant's attitude toward the male acquaintance (liked vs. uninteresting) and (2) the type of the gift (romantic [e.g., bouquet, earrings, and perfumes] vs. non-romantic [e.g., pencils, memo pad, and moneybox]). We found that preference for an acquaintance selectively modulated activity in the anterior cingulate cortex (ACC) in response to romantic gifts, compared to non-romantic gifts. In contrast, if the woman was indifferent toward an acquaintance, no activity modulation was observed in this area for the same gifts. In addition, the ACC showed functional connectivity with the supplementary motor area/dorsal ACC (SMA/dACC), an area within the dorsal mediofrontal cortex, suggesting that it integrates action monitoring and emotional and cognitive processing in decision-making. These results suggest that attitude toward an opposite sex member has a modulatory role in recognizing the social meaning of material goods--preference for the member is a powerful modulator of social reward processing.
Nakagawa, Jun; Takahashi, Muneyoshi; Okada, Rieko; Matsushima, Eisuke; Matsuda, Tetsuya
2015-01-01
Men, like the male of many animal species, use gifts to build satisfactory relationships with a desired woman. From the woman’s perspective, all gifts are not always equally rewarding; the reward value of a gift depends on two factors: (1) the giver and (2) the type of the gift (the gift’s social meaning). In this study, we investigated how these two factors interactively determine the reward value of a gift. Specifically, we examined how the neural processing for understanding a gift’s social meaning is modulated by preferences for the giver. We performed a functional magnetic resonance imaging (fMRI) study in which a female participant was asked to judge a gift from a male she was acquainted with in real life. We examined the interactive effects between (1) the female participant’s attitude toward the male acquaintance (liked vs. uninteresting) and (2) the type of the gift (romantic [e.g., bouquet, earrings, and perfumes] vs. non-romantic [e.g., pencils, memo pad, and moneybox]). We found that preference for an acquaintance selectively modulated activity in the anterior cingulate cortex (ACC) in response to romantic gifts, compared to non-romantic gifts. In contrast, if the woman was indifferent toward an acquaintance, no activity modulation was observed in this area for the same gifts. In addition, the ACC showed functional connectivity with the supplementary motor area/dorsal ACC (SMA/dACC), an area within the dorsal mediofrontal cortex, suggesting that it integrates action monitoring and emotional and cognitive processing in decision-making. These results suggest that attitude toward an opposite sex member has a modulatory role in recognizing the social meaning of material goods—preference for the member is a powerful modulator of social reward processing. PMID:26301954
2014-01-01
Background Diabetes education and self-care remains the cornerstone of diabetes management. There are many structured diabetes modules available in the United Kingdom, Europe and United States of America. Contrastingly, few structured and validated diabetes modules are available in Malaysia. This pilot study aims to develop and validate diabetes education material suitable and tailored for a multicultural society like Malaysia. Methods The theoretical framework of this module was founded from the Health Belief Model (HBM). The participants were assessed using 6-item pre- and post-test questionnaires that measured some of the known HBM constructs namely cues to action, perceived severity and perceived benefit. Data was analysed using PASW Statistics 18.0. Results The pre- and post-test questionnaires were administered to 88 participants (31 males). In general, there was a significant increase in the total score in post-test (97.34 ± 6.13%) compared to pre-test (92.80 ± 12.83%) (p < 0.05) and a significant increase in excellent score (>85%) at post-test (84.1%) compared to pre-test (70.5%) (p < 0.05). There was an improvement in post-test score in 4 of 6 items tested. The remaining 2 items which measured the perceived severity and cues to action had poorer post-test score. Conclusions The preliminary results from this pilot study suggest contextualised content material embedded within MY DEMO maybe suitable for integration with the existing diabetes education programmes. This was the first known validated diabetes education programme available in the Malay language. PMID:24708715
Lv, Hui; Yu, Yonglin; Shu, Tan; Huang, Dexiu; Jiang, Shan; Barry, Liam P
2010-03-29
Photonic ultra-wideband (UWB) pulses are generated by direct current modulation of a semiconductor optical amplifier (SOA) section of an SOA-integrated sampled grating distributed Bragg reflector (SGDBR) laser. Modulation responses of the SOA section of the laser are first simulated with a microwave equivalent circuit model. Simulated results show a resonance behavior indicating the possibility to generate UWB signals with complex shapes in the time domain. The UWB pulse generation is then experimentally demonstrated for different selected wavelength channels with an SOA-integrated SGDBR laser.
Distributed multisensory integration in a recurrent network model through supervised learning
NASA Astrophysics Data System (ADS)
Wang, He; Wong, K. Y. Michael
Sensory integration between different modalities has been extensively studied. It is suggested that the brain integrates signals from different modalities in a Bayesian optimal way. However, how the Bayesian rule is implemented in a neural network remains under debate. In this work we propose a biologically plausible recurrent network model, which can perform Bayesian multisensory integration after trained by supervised learning. Our model is composed of two modules, each for one modality. We assume that each module is a recurrent network, whose activity represents the posterior distribution of each stimulus. The feedforward input on each module is the likelihood of each modality. Two modules are integrated through cross-links, which are feedforward connections from the other modality, and reciprocal connections, which are recurrent connections between different modules. By stochastic gradient descent, we successfully trained the feedforward and recurrent coupling matrices simultaneously, both of which resembles the Mexican-hat. We also find that there are more than one set of coupling matrices that can approximate the Bayesian theorem well. Specifically, reciprocal connections and cross-links will compensate each other if one of them is removed. Even though trained with two inputs, the network's performance with only one input is in good accordance with what is predicted by the Bayesian theorem.
Independent learning modules enhance student performance and understanding of anatomy.
Serrat, Maria A; Dom, Aaron M; Buchanan, James T; Williams, Alison R; Efaw, Morgan L; Richardson, Laura L
2014-01-01
Didactic lessons are only one part of the multimodal teaching strategies used in gross anatomy courses today. Increased emphasis is placed on providing more opportunities for students to develop lifelong learning and critical thinking skills during medical training. In a pilot program designed to promote more engaged and independent learning in anatomy, self-study modules were introduced to supplement human gross anatomy instruction at Joan C. Edwards School of Medicine at Marshall University. Modules use three-dimensional constructs to help students understand complex anatomical regions. Resources are self-contained in portable bins and are accessible at any time. Students use modules individually or in groups in a structured self-study format that augments material presented in lecture and laboratory. Pilot outcome data, measured by feedback surveys and examination performance statistics, suggest that the activity may be improving learning in gross anatomy. Positive feedback on both pre- and post-examination surveys showed that students felt the activity helped to increase their understanding of the topic. In concordance with student perception, average examination scores on module-related laboratory and lecture questions were higher in the two years of the pilot program compared with the year before its initiation. Modules can be fabricated on a modest budget using minimal resources, making implementation practical for smaller institutions. Upper level medical students assist in module design and upkeep, enabling continuous opportunities for vertical integration across the curriculum. This resource offers a feasible mechanism for enhancing independent and lifelong learning competencies, which could be a valuable complement to any gross anatomy curriculum. © 2014 American Association of Anatomists.
NASA Technical Reports Server (NTRS)
Pedley, M. D.; Mayeaux, B.
2001-01-01
A viewgraph presentation gives an overview of the materials selection for the TransHab, the habitation module on the International Space Station (ISS). Details are given on the location of TransHab on the ISS, the multilayer inflatable shell that surrounds the module, the materials requirements (including information on the expected thermal environment), the materials selection challenges, the bladder materials requirements and testing, and meteoroid/debris shielding material.
50 Gb/s hybrid silicon traveling-wave electroabsorption modulator.
Tang, Yongbo; Chen, Hui-Wen; Jain, Siddharth; Peters, Jonathan D; Westergren, Urban; Bowers, John E
2011-03-28
We have demonstrated a traveling-wave electroabsorption modulator based on the hybrid silicon platform. For a device with a 100 μm active segment, the small-signal electro/optical response renders a 3 dB bandwidth of around 42 GHz and its modulation efficiency reaches 23 GHz/V. A dynamic extinction ratio of 9.8 dB with a driving voltage swing of only 2 V was demonstrated at a transmission rate of 50 Gb/s. This represents a significant improvement for modulators compatible with integration of silicon-based photonic integrated circuits.
Integrated restructurable flight control system demonstration results
NASA Technical Reports Server (NTRS)
Weiss, Jerold L.; Hsu, John Y.
1987-01-01
The purpose of this study was to examine the complementary capabilities of several restructurable flight control system (RFCS) concepts through the integration of these technologies into a complete system. Performance issues were addressed through a re-examination of RFCS functional requirements, and through a qualitative analysis of the design issues that, if properly addressed during integration, will lead to the highest possible degree of fault-tolerant performance. Software developed under previous phases of this contract and under NAS1-18004 was modified and integrated into a complete RFCS subroutine for NASA's B-737 simulation. The integration of these modules involved the development of methods for dealing with the mismatch between the outputs of the failure detection module and the input requirements of the automatic control system redesign module. The performance of this demonstration system was examined through extensive simulation trials.
NASA Astrophysics Data System (ADS)
Egger, A. E.; Baldassari, C.; Bruckner, M. Z.; Iverson, E. A.; Manduca, C. A.; Mcconnell, D. A.; Steer, D. N.
2013-12-01
InTeGrate is NSF's STEP Center in the geosciences. A major goal of the project is to develop curricula that will increase the geoscience literacy of all students such that they are better positioned to make sustainable decisions in their lives and as part of the broader society. This population includes the large majority of students that do not major in the geosciences, those historically under-represented in the geosciences, and future K-12 teachers. To achieve this goal, we established a model for the development of curricular materials that draws on the distributed expertise of the undergraduate teaching community. Our model seeks proposals from across the higher education community for courses and modules that meet InTeGrate's overarching goals. From these proposals, we select teams of 3-5 instructors from three or more different institutions (and institution types) and pair them with assessment and web experts. Their communication and development process is supported by a robust, web-based content management system (CMS). Over two years, this team develops materials that explicitly address a geoscience-related societal challenge, build interdisciplinary problem-solving skills, make use of real geoscience data, and incorporate geoscientific and systems thinking. Materials are reviewed with the InTeGrate design rubric and then tested by the authors in their own courses, where student learning is assessed. Results are reviewed by the authors and our assessment team to guide revisions. Several student audiences are targeted: students in general education and introductory geoscience courses, pre-service K-12 teachers, students in other science and engineering majors, as well as those in the humanities and social sciences. Curriculum development team members from beyond the geosciences are critical to producing materials that can be adopted for all of these audiences, and we have been successful in engaging faculty from biology, economics, engineering, sociology, Spanish, and other disciplines. In its first year, InTeGrate engaged 20 individuals from 17 different institutions on materials development teams. During interviews and responses to open-ended survey questions, first-year team members provided feedback about the challenges and successes of the model. Several described that the materials design rubric was a useful tool in guiding their work and pushed them in directions they may not have otherwise gone. Most responded that working as part of a team with members from different institutions created numerous challenges, but was ultimately beneficial in sharing ideas and resulted in a better product. Other key components to model success are the development of resources by the web experts to support use of the CMS and frequent feedback from the assessment team. All feedback was used to refine the model for the second year, during which 56 additional authors have begun to develop materials. By engaging this broad and diverse community in innovative curriculum development, we anticipate widespread adoption of InTeGrate materials.
ERIC Educational Resources Information Center
Carson, Diane
This curriculum module offers concrete and specific examples for instructors who wish to integrate the films of Yasujiro Ozu of Japan and Zhang Yimou from China into film studies courses. Through this module, students should learn to compare and contrast conventional screen space, color, and editing to alternative forms. By becoming more familiar…
Josephson junction microwave modulators for qubit control
NASA Astrophysics Data System (ADS)
Naaman, O.; Strong, J. A.; Ferguson, D. G.; Egan, J.; Bailey, N.; Hinkey, R. T.
2017-02-01
We demonstrate Josephson junction based double-balanced mixer and phase shifter circuits operating at 6-10 GHz and integrate these components to implement both a monolithic amplitude/phase vector modulator and an I/Q quadrature mixer. The devices are actuated by flux signals, dissipate no power on chip, exhibit input saturation powers in excess of 1 nW, and provide cryogenic microwave modulation solutions for integrated control of superconducting qubits.
Ray, Sumanta; Maulik, Ujjwal
2016-12-20
Detecting perturbation in modular structure during HIV-1 disease progression is an important step to understand stage specific infection pattern of HIV-1 virus in human cell. In this article, we proposed a novel methodology on integration of multiple biological information to identify such disruption in human gene module during different stages of HIV-1 infection. We integrate three different biological information: gene expression information, protein-protein interaction information and gene ontology information in single gene meta-module, through non negative matrix factorization (NMF). As the identified metamodules inherit those information so, detecting perturbation of these, reflects the changes in expression pattern, in PPI structure and in functional similarity of genes during the infection progression. To integrate modules of different data sources into strong meta-modules, NMF based clustering is utilized here. Perturbation in meta-modular structure is identified by investigating the topological and intramodular properties and putting rank to those meta-modules using a rank aggregation algorithm. We have also analyzed the preservation structure of significant GO terms in which the human proteins of the meta-modules participate. Moreover, we have performed an analysis to show the change of coregulation pattern of identified transcription factors (TFs) over the HIV progression stages.
Makedonska, Jana; Wright, Barth W.; Strait, David S.
2012-01-01
A fundamental challenge of morphology is to identify the underlying evolutionary and developmental mechanisms leading to correlated phenotypic characters. Patterns and magnitudes of morphological integration and their association with environmental variables are essential for understanding the evolution of complex phenotypes, yet the nature of the relevant selective pressures remains poorly understood. In this study, the adaptive significance of morphological integration was evaluated through the association between feeding mechanics, ingestive behavior and craniofacial variation. Five capuchin species were examined, Cebus apella sensu stricto, Cebus libidinosus, Cebus nigritus, Cebus olivaceus and Cebus albifrons. Twenty three-dimensional landmarks were chosen to sample facial regions experiencing high strains during feeding, characteristics affecting muscular mechanical advantage and basicranial regions. Integration structure and magnitude between and within the oral and zygomatic subunits, between and within blocks maximizing modularity and within the face, the basicranium and the cranium were examined using partial-least squares, eigenvalue variance, integration indices compared inter-specifically at a common level of sampled population variance and cluster analyses. Results are consistent with previous findings reporting a relative constancy of facial and cranial correlation patterns across mammals, while covariance magnitudes vary. Results further suggest that food material properties structure integration among functionally-linked facial elements and possibly integration between the face and the basicranium. Hard-object-feeding capuchins, especially C.apella s.s., whose faces experience particularly high biomechanical loads are characterized by higher facial and cranial integration especially compared to C.albifrons, likely because morphotypes compromising feeding performance are selected against in species relying on obdurate fallback foods. This is the first study to report a link between food material properties and facial and cranial integration. Furthermore, results do not identify the consistent presence of cranial modules yielding support to suggestions that despite the distinct embryological imprints of its elements the cranium of placental mammals is not characterized by a modular architecture. PMID:23110039
Brains striving for coherence: Long-term cumulative plot formation in the default mode network.
Tylén, K; Christensen, P; Roepstorff, A; Lund, T; Østergaard, S; Donald, M
2015-11-01
Many everyday activities, such as engaging in conversation or listening to a story, require us to sustain attention over a prolonged period of time while integrating and synthesizing complex episodic content into a coherent mental model. Humans are remarkably capable of navigating and keeping track of all the parallel social activities of everyday life even when confronted with interruptions or changes in the environment. However, the underlying cognitive and neurocognitive mechanisms of such long-term integration and profiling of information remain a challenge to neuroscience. While brain activity is generally traceable within the short time frame of working memory (milliseconds to seconds), these integrative processes last for minutes, hours or even days. Here we report two experiments on story comprehension. Experiment I establishes a cognitive dissociation between our comprehension of plot and incidental facts in narratives: when episodic material allows for long-term integration in a coherent plot, we recall fewer factual details. However, when plot formation is challenged, we pay more attention to incidental facts. Experiment II investigates the neural underpinnings of plot formation. Results suggest a central role for the brain's default mode network related to comprehension of coherent narratives while incoherent episodes rather activate the frontoparietal control network. Moreover, an analysis of cortical activity as a function of the cumulative integration of narrative material into a coherent story reveals to linear modulations of right hemisphere posterior temporal and parietal regions. Together these findings point to key neural mechanisms involved in the fundamental human capacity for cumulative plot formation. Copyright © 2015 Elsevier Inc. All rights reserved.
Investigation of test methods, material properties, and processes for solar cell encapsulants
NASA Technical Reports Server (NTRS)
Willis, P. B.
1983-01-01
A study of potentially useful low cost encapsulation materials for the Flat-Plate Solar Array project is discussed. The goal is to identify, evaluate, test and recommend encapsulant materials and processes for the production of cost-effective, long life solar cell modules. Technical investigations included studies of aging and degradation of candidate encapsulation materials, continued identification of primers for durable bonding of module interfaces, continued evaluation of soil resistant treatments for the sunlit surface of the module and testing of corrosion protective coatings for use low cost mild steel substrates.
AIDA: An Integrated Authoring Environment for Educational Software.
ERIC Educational Resources Information Center
Mendes, Antonio Jose; Mendes, Teresa
1996-01-01
Describes an integrated authoring environment, AIDA ("Ambiente Integrado de Desenvolvimento de Aplicacoes educacionais"), that was developed at the University of Coimbra (Portugal) for educational software. Highlights include the design module, a prototyping tool that allows for multimedia, simulations, and modularity; execution module;…
Candidate materials for advanced fire-resistant photovoltaic modules
NASA Technical Reports Server (NTRS)
Sugimura, R. S.; Otth, D. H.; Ross, R. G., Jr.; Arnett, J. C.; Samuelson, G.
1985-01-01
A cooperative, cost-sharing research effort to develop a technology base required to construct fire-ratable photovoltaic modules has resulted in the identification of several high-temperature, back-surface candidate materials capable of raising the fire-resistance of modules using hydrocarbon encapsulants to Class A and B levels. Advanced experimental module configurations have been developed using back surfaces consisting of Kapton, Tedlar laminates, metal-foils, and fiberglass materials with high-temperature coatings. Test results (October 1984; March 1985; May 1985; and October 1985) indicate that several of these advanced module configurations are capable of achieving Class B fire-resistance levels, while a few configurations can achieve Class A levels. The paper summarizes activities to date, discussing flammability failure mechanisms, time-temperature profiles, and results of Block V environmental exposure tests of a candidate material suitable for both Class B and Class A fire-resistance levels.
Planetary Exploration Education: As Seen From the Point of View of Subject Matter Experts
NASA Astrophysics Data System (ADS)
Milazzo, M. P.; Anderson, R. B.; Gaither, T. A.; Vaughan, R. G.
2016-12-01
Planetary Learning that Advances the Nexus of Engineering, Technology, and Science (PLANETS) was selected as one of 27 new projects to support the NASA Science Mission Directorate's Science Education Cooperative Agreement Notice. Our goal is to develop and disseminate out-of-school time (OST) curricular and related educator professional development modules that integrate planetary science, technology, and engineering. We are a partnership between planetary science Subject Matter Experts (SMEs), curriculum developers, science and engineering teacher professional development experts and OST teacher networks. The PLANETS team includes the Center for Science Teaching and Learning (CSTL) at Northern Arizona University (NAU); the U.S. Geological Survey (USGS) Astrogeology Science Center (Astrogeology), and the Boston Museum of Science (MOS). Here, we present the work and approach by the SMEs at Astrogeology. As part of this overarching project, we will create a model for improved integration of SMEs, curriculum developers, professional development experts, and educators. For the 2016 and 2017 Fiscal Years, our focus is on creating science material for two OST modules designed for middle school students. We will begin development of a third module for elementary school students in the latter part of FY2017. The first module focuses on water conservation and treatment as applied on Earth, the International Space Station, and at a fictional Mars base. This unit involves the science and engineering of finding accessible water, evaluating it for quality, treating it for impurities (i.e., dissolved and suspended), initial use, a cycle of greywater treatment and re-use, and final treatment of blackwater. The second module involves the science and engineering of remote sensing as it is related to Earth and planetary exploration. This includes discussion and activities related to the electromagnetic spectrum, spectroscopy and various remote sensing systems and techniques. In these activities and discussions we include observation and measurement techniques and tools, as well as collection and use of specific data of interest to scientists. These two modules will be tested and refined based on educator and student feedback, with expected final release in late summer of 2017.
Large-Aperture Membrane Active Phased-Array Antennas
NASA Technical Reports Server (NTRS)
Karasik, Boris; McGrath, William; Leduc, Henry
2009-01-01
Large-aperture phased-array microwave antennas supported by membranes are being developed for use in spaceborne interferometric synthetic aperture radar systems. There may also be terrestrial uses for such antennas supported on stationary membranes, large balloons, and blimps. These antennas are expected to have areal mass densities of about 2 kg/sq m, satisfying a need for lightweight alternatives to conventional rigid phased-array antennas, which have typical areal mass densities between 8 and 15 kg/sq m. The differences in areal mass densities translate to substantial differences in total mass in contemplated applications involving aperture areas as large as 400 sq m. A membrane phased-array antenna includes patch antenna elements in a repeating pattern. All previously reported membrane antennas were passive antennas; this is the first active membrane antenna that includes transmitting/receiving (T/R) electronic circuits as integral parts. Other integral parts of the antenna include a network of radio-frequency (RF) feed lines (more specifically, a corporate feed network) and of bias and control lines, all in the form of flexible copper strip conductors on flexible polymeric membranes. Each unit cell of a prototype antenna (see Figure 1) contains a patch antenna element and a compact T/R module that is compatible with flexible membrane circuitry. There are two membrane layers separated by a 12.7-mm air gap. Each membrane layer is made from a commercially available flexible circuit material that, as supplied, comprises a 127-micron-thick polyimide dielectric layer clad on both sides with 17.5-micron-thick copper layers. The copper layers are patterned into RF, bias, and control conductors. The T/R module is located on the back side of the ground plane and is RF-coupled to the patch element via a slot. The T/R module is a hybrid multilayer module assembled and packaged independently and attached to the membrane array. At the time of reporting the information for this article, an 8 16 passive array (not including T/R modules) and a 2 4 active array (including T/R modules) had been demonstrated, and it was planned to fabricate and test larger arrays.
Long, Yun; Zhou, Linjie; Wang, Jian
2016-01-01
Photonic generation of microwave signal is obviously attractive for many prominent advantages, such as large bandwidth, low loss, and immunity to electromagnetic interference. Based on a single integrated silicon Mach–Zehnder modulator (MZM), we propose and experimentally demonstrate a simple and compact photonic scheme to enable frequency-multiplicated microwave signal. Using the fabricated integrated MZM, we also demonstrate the feasibility of microwave amplitude-shift keying (ASK) modulation based on integrated photonic approach. In proof-of-concept experiments, 2-GHz frequency-doubled microwave signal is generated using a 1-GHz driving signal. 750-MHz/1-GHz frequency-tripled/quadrupled microwave signals are obtained with a driving signal of 250 MHz. In addition, a 50-Mb/s binary amplitude coded 1-GHz microwave signal is also successfully generated. PMID:26832305
Efficiently and easily integrating differential equations with JiTCODE, JiTCDDE, and JiTCSDE
NASA Astrophysics Data System (ADS)
Ansmann, Gerrit
2018-04-01
We present a family of Python modules for the numerical integration of ordinary, delay, or stochastic differential equations. The key features are that the user enters the derivative symbolically and it is just-in-time-compiled, allowing the user to efficiently integrate differential equations from a higher-level interpreted language. The presented modules are particularly suited for large systems of differential equations such as those used to describe dynamics on complex networks. Through the selected method of input, the presented modules also allow almost complete automatization of the process of estimating regular as well as transversal Lyapunov exponents for ordinary and delay differential equations. We conceptually discuss the modules' design, analyze their performance, and demonstrate their capabilities by application to timely problems.
Pattern manipulation via on-chip phase modulation between orbital angular momentum beams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Huanlu; School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LP; Strain, Michael J.
2015-08-03
An integrated approach to thermal modulation of relative phase between two optical vortices with opposite chirality has been demonstrated on a silicon-on-insulator substrate. The device consists of a silicon-integrated optical vortex emitter and a phase controlled 3 dB coupler. The relative phase between two optical vortices can be actively modulated on chip by applying a voltage on the integrated heater. The phase shift is shown to be linearly proportional to applied electrical power, and the rotation angle of the interference pattern is observed to be inversely proportional to topological charge. This scheme can be used in lab-on-chip, communications and sensing applications.more » It can be intentionally implemented with other modulation elements to achieve more complicated applications.« less
Application de la technologie des materiaux sol-gel et polymere a l'optique integree
NASA Astrophysics Data System (ADS)
Saddiki, Zakaria
2002-01-01
With the advancement of optical telecommunication systems, "integrated optics" and "optical interconnect" technology are becoming more and more important. The major components of these two technologies are photonic integrated circuits (PICs), optoelectronic integrated circuits (OEICs), and optoelectronic multichip modules ( OE-MCMs). Optical signals are transmitted through optical waveguides that interconnect such components. The principle of optical transmission in waveguides is the same as that in optical fibres. To implement these technologies, both passive and active optical devices are needed. A wide variety of optical materials has been studied, e.g., glasses, lithium niobate, III-V semiconductors, sol-gel and polymers. In particular, passive optical components have been fabricated using glass optical waveguides by ion-exchange, or by flame hydrolysis deposition and reactive ion etching (FHD and RIE ). When using FHD and RIE, a very high temperatures (up to 1300°C) are needed to consolidate silica. This work reports on the fabrication and characterization of a new photo-patternable hybrid organic-inorganic glass sol-gel and polymer materials for the realisation of integrated optic and opto-electronic devices. They exhibit low losses in the NIR range, especially at the most important wavelengths windows for optical communications (1320 nm and 1550 nm). The sol-gel and polymer process is based on photo polymerization and thermo polymerization effects to create the wave-guide. The single-layer film is at low temperature and deep UV-light is employed to make the wave-guide by means of the well-known photolithography process. Like any photo-imaging process, the UV energy should exceed the threshold energy of chemical bonds in the photoactive component of hybrid glass material to form the expected integrated optic pattern with excellent line width control and vertical sidewalls. To achieve optical wave-guide, a refractive index difference Delta n occurred between the isolated (guiding layer) and the surrounding region (buffer and cladding). Accordingly, the refractive index emerges as a fundamental device performance material parameter and it is investigated using slab wave-guide. (Abstract shortened by UMI.)
NASA Astrophysics Data System (ADS)
Bessonov, O.; Silvestrov, P.
2017-02-01
This paper describes the general idea and the first implementation of the Interactive information and simulation system - an integrated environment that combines computational modules for modeling the aerodynamics and aerothermodynamics of re-entry space vehicles with the large collection of different information materials on this topic. The internal organization and the composition of the system are described and illustrated. Examples of the computational and information output are presented. The system has the unified implementation for Windows and Linux operation systems and can be deployed on any modern high-performance personal computer.
OA-7 Atlas V Centaur mate to Booster
2017-02-23
The Centaur upper stage of the United Launch Alliance (ULA) Atlas V rocket arrives at the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The Centaur stage is lifted and mated to the first stage booster. The rocket is being prepared for Orbital ATK's seventh commercial resupply mission, CRS-7, to the International Space Station. Orbital ATK's CYGNUS pressurized cargo module is scheduled to launch atop ULA's Atlas V rocket from Pad 41 on March 19, 2017. CYGNUS will deliver 7,600 of pounds of supplies, equipment and scientific research materials to the space station
Atlas V OA-7 LVOS Atlas Booster on Stand
2017-02-22
The first stage of the United Launch Alliance (ULA) Atlas V rocket is lifted by crane to vertical as it is moved into the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The rocket is being prepared for Orbital ATK's seventh commercial resupply mission, CRS-7, to the International Space Station. Orbital ATK's CYGNUS pressurized cargo module is scheduled to launch atop ULA's Atlas V rocket from Pad 41 on March 19, 2017. CYGNUS will deliver thousands of pounds of supplies, equipment and scientific research materials to the space station