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According to one embodiment, a method includes incorporating a metal carboxylate complex into a polymeric matrix to form an optically transparent material. According to another embodiment, a material includes at least one metal carboxylate complex incorporated into a polymeric matrix, where the material is optically transparent.
High performance, high bandgap, lattice-mismatched, photovoltaic cells (10), both transparent and non-transparent to sub-bandgap light, are provided as devices for use alone or in combination with other cells in split spectrum apparatus or other applications.
A thin film photovoltaic device (100) with a tunable, minimally conductive buffer (128) layer is provided. The photovoltaic device (100) may include a back contact (150), a transparent front contact stack (120), and an absorber (140) positioned between the front contact stack (120) and the back contact (150). The front contact stack (120) may include a low resistivity transparent conductive oxide (TCO) layer (124) and a buffer layer (128) that is proximate to the absorber layer (140). The photovoltaic device (100) may also include a window layer (130) between the buffer layer (128) and the absorber (140). In some cases, the buffer layer (128) is minimally conductive, with its resistivity being tunable, and the buffer layer (128) may be formed as an alloy from a host oxide and a high-permittivity oxide. The high-permittivity oxide may further be chosen to have a bandgap greater than the host oxide.
In the ongoing evolution of International Atomic Energy Agency (IAEA) safeguards at the state level, many safeguards implementation principles have been emphasized: effectiveness, efficiency, non-discrimination, transparency, focus on sensitive materials, centrality of material accountancy for detecting diversion, independence, objectivity, and grounding in technical considerations, among others. These principles are subject to differing interpretations and prioritizations and sometimes conflict. This paper is an attempt to develop metrics and address some of the potential tradeoffs inherent in choices about how various safeguards policy principles are implemented. The paper carefully defines effective safeguards, including in the context of safeguards approaches that take account of the range of state-specific factors described by the IAEA Secretariat and taken note of by the Board in September 2014, and (2) makes use of performance metrics to help document, and to make transparent, how safeguards implementation would meet such effectiveness requirements.
A pixelated gamma detector includes a scintillator column assembly having scintillator crystals and optical transparent elements alternating along a longitudinal axis, a collimator assembly having longitudinal walls separated by collimator septum, the collimator septum spaced apart to form collimator channels, the scintillator column assembly positioned adjacent to the collimator assembly so that the respective ones of the scintillator crystal are positioned adjacent to respective ones of the collimator channels, the respective ones of the optical transparent element are positioned adjacent to respective ones of the collimator septum, and a first photosensor and a second photosensor, the first and the second photosensor each connected to an opposing end of the scintillator column assembly. A system and a method for inspecting and/or detecting defects in an interior of an object are also disclosed.
The present invention relates to a test chamber that can be used to perform a variety of X-ray and neutron spectroscopy experiments including powder diffraction, small-angle scattering, X-ray absorption spectroscopy, and pair distribution functions, such chamber comprising a first electrode with an X-ray transparent window; a second electrode with an X-ray transparent window; a plurality of insulating gaskets providing a hermetic seal around the sample and preventing contact between said first and second electrodes; and an insulating housing into which the first electrode is secured.
In 2016, the Office of International Nuclear Safeguards at the National Nuclear Security Administration (NNSA) within the Department of Energy (DOE) commissioned the Pacific Northwest National Laboratory (PNNL) to explore the potential implications of the digital currency bitcoin and its underlying technologies on the safeguards system. The authors found that one category of technologies referred to as Shared Ledger Technology (SLT) offers a spectrum of benefits to the safeguards system. While further research is needed to validate assumptions and findings in the paper, preliminary analysis suggests that both the International Atomic Energy Agency (IAEA) and Member States can use SLT to promote efficient, effective, accurate, and timely reporting, and increase transparency in the safeguards system without sacrificing confidentiality of safeguards data. This increased transparency and involvement of Member States in certain safeguards transactions could lead to increased trust and cooperation among States and the public, which generates a number of benefits. This paper describes these benefits and the analytical framework for assessing SLT applications for specific safeguards problems. The paper will also describe other national security areas where SLT could provide benefits.
Provenance describes detailed information about the history of a piece of data, containing the relationships among elements such as users, processes, jobs, and workflows that contribute to the existence of data. Provenance is key to supporting many data management functionalities that are increasingly important in operations such as identifying data sources, parameters, or assumptions behind a given result; auditing data usage; or understanding details about how inputs are transformed into outputs. Despite its importance, however, provenance support is largely underdeveloped in highly parallel architectures and systems. One major challenge is the demanding requirements of providing provenance service in situ. The need to remain lightweight and to be always on often conflicts with the need to be transparent and offer an accurate catalog of details regarding the applications and systems. To tackle this challenge, we introduce a lightweight provenance service, called LPS, for high-performance computing (HPC) systems. LPS leverages a kernel instrument mechanism to achieve transparency and introduces representative execution and flexible granularity to capture comprehensive provenance with controllable overhead. Extensive evaluations and use cases have confirmed its efficiency and usability. We believe that LPS can be integrated into current and future HPC systems to support a variety of data management needs.
An optical system and method to overcome luminescent solar concentrator inefficiencies by resonance-shifting, in which sharply directed emission from a bi-layer cavity into a glass substrate returns to interact with the cavity off-resonance at each subsequent reflection, significantly reducing reabsorption loss en route to the edges. In one embodiment, the system comprises a luminescent solar concentrator comprising a transparent substrate, a luminescent film having a variable thickness; and a low refractive index layer disposed between the transparent substrate and the luminescent film.
An electrochromic device may be switchable between a transparent state and at least one reflective state. A lithium-containing reflective feature may form when the electrochromic device is switched from the transparent state to the reflective state. Various products and methods may involve the electrochromic device.
Aspects of the present disclosure are directed to providing and/or controlling electromagnetic radiation. As may be implemented in accordance with one or more embodiments, an apparatus includes a first structure that contains an object, and a second structure that is transparent at solar wavelengths and emissive in the atmospheric electromagnetic radiation transparency window. The second structure operates with the first structure to pass light into the first structure for illuminating the object, and to radiatively cool the object while preserving the object's color.
An apparatus, method, and system, the apparatus and system including a flexible microsystems enabled microelectronic device package including a microelectronic device positioned on a substrate; an encapsulation layer encapsulating the microelectronic device and the substrate; a protective layer positioned around the encapsulating layer; and a reinforcing layer coupled to the protective layer, wherein the substrate, encapsulation layer, protective layer and reinforcing layer form a flexible and optically transparent package around the microelectronic device. The method including encapsulating a microelectronic device positioned on a substrate within an encapsulation layer; sealing the encapsulated microelectronic device within a protective layer; and coupling the protective layer to a reinforcing layer, wherein the substrate, encapsulation layer, protective layer and reinforcing layer form a flexible and optically transparent package around the microelectronic device.
There are critical material and scientific barriers to producing high efficiency, flexible, lightweight solar cells that maximize specific power in a cost-effective manner. GaAs solar cells produce the highest specific power of any photovoltaic (PV) technology due to their low weight and extremely high efficiency, but they are also among the most expensive to produce. This work explores a novel lift-off approach with thin-film solar cells, particularly CdTe, to achieve high specific power at low costs. Thin-film devices can be delaminated from their heavy, glass growth substrates post-growth by exploiting a mismatch in coefficient of thermal expansion between the two. This allows thin-film PV to be decoupled from high temperature growth requirements and repackaged using lightweight materials. Currently, the most consistent method of achieving complete delamination of CdTe films is to apply a glass handle at the back contact of the device using epoxy and submerge it in liquid nitrogen. By Tthen re-depositing a transparent front contact but be re-deposited and selectively etcheding to expose the back contact to produce, a functioning lifted-off devices have been produced. Effects of delamination and contributions to device functionality from CdCl2 and CdS layers are discussed. Reproducible delamination of high efficiency, thin-film solar cells over large areas will enable work to further improve device efficiency through passivation and reconstruction of the previously buried interface between the transparent contact and CdS.
An electrochromic device may be switchable between a transparent state and at least one reflective state. A lithium-containing reflective feature may form when the electrochromic device is switched from the transparent state to the reflective state. Various products and methods may involve the electrochromic device.
The past 24 months has been one of non-stop continuous improvement – every month, every week, every day, and every hour. It has been filled with continuously re-examining and challenging business systems, work processes, and legacy culture. The journey was difficult, but well worth it. It began by examining the existing conditions in each organization and building the case for change. When we stepped back and looked at our processes, systems, tools, and performance objectively, we realized we were struggling with frequent organizational, resource, and schedule conflicts, work processes that were not well-defined or expert based, project delays were common, management methods were predominantly reactive, advanced planning was limited to the near-term, no integration in scheduling across organizations, limited to no performance metrics to measure and manage performance, and internal and external customers did not feel like we were meeting their quality and performance expectations. It was a wake-up call. Change began at the top with a change leadership with where a new vision, expectations, and commitment were established. Leaving no stone left unturned, every aspect of the business was challenged which opened up communication and exposed the gaps. This was done in a ‘safe’ environment allowing for honest and solution-oriented discussion and action. The leadership team committed to managing through continuous improvement. The organizational structure was realigned to better align scope, responsibilities, execution, and customer focus. Visibility and transparency became the norm as higher levels of leadership and supporting organizations were invited to be part of regular strategy meetings and partnership discussion, effectively opening up the dialogue. This required a tremendous amount of trust and faith in a short period of time. Health assessments were conducted on each organization with specific lines of inquiry. These self-assessments helped to identify better define the scope of the organization and where targeted improvements were needed. Frequent organizational reviews were implemented to answer three fundamental questions: 1) What is your organization paid to do (scope)?, 2) How does your organization, or you, demonstrate that you are doing the job effectively?, and 3) What are you doing to improve your performance? To answer the first question, leaders defined the scope of the organization. Leaders were required to provide a path forward, with specific actions, where performance was not at expected levels internally at first and then from the stakeholders. Where business processes were not clearly understood, process maps were developed to provide this clarity for both those performing the work and those utilizing the process – the customers. To help answer the second question, numerous automated or semi-automated real-time, dynamic performance metrics were developed and implement to help leaders gain the visibility and demonstrate performance in six areas of operational excellence: safety, security, quality, effectiveness, productivity, and sustainability. Analysis of the performance provided windows of transparency and trends of work performance, work delays, cycle times, utilization, and much more that revealed many areas of improvement that were either not visible or desired to be visible. At the same time, they provided real-time progress which generated initial performance improvements by just beginning to measure. To address the third question, where systems did not support effectiveness of an existing or new process, then systems and tools were developed and implemented to drive the right behaviors and reinforce the processes. Tools and metrics were one of the major catalysts for culture shift and change. Risk assessments were leveraged into continuous improvement strategies, plans, and schedules. Targeted initiatives were identified and performed. Change and improvement was not, and is not, without significant and common challenges including limited/fixed budgets, resource availability, data access, natural resistance to change, and numerous other reasons or excuses – we called them ‘off-ramps’ and began to close them one-by-one. The results and outputs were significant and impactful in each organization and across the business with increased productivity, efficiency, visibility, accountability, management, and performance. Stakeholder satisfaction also increased. Cost and time savings allowed to more continuous improvement efforts to be performed. The effort clearly provided clear and measurable return on investment and value. Efforts that once seemed impossible, not feasible, or not achievable were performed. Decades-long issues were solved. ‘Impossible things are simply those which so far have never been done’ said Elbert Hubbard. So what will the next year be for you and your organization? Are you satisfied with the ‘same ‘ol, same ‘ol?’ Will you fall into the complacency trap and believe that change is too difficult, too expensive, and not necessary (or any number of possible excuses) or will you make this year your year or continuous improvement (and every year thereafter…)? Remember – what you do today can improve all your tomorrows’ (Ralph Marston).
Heterogeneous computing with accelerators is growing in importance in high performance computing (HPC). Recently, application datasets have expanded beyond the memory capacity of these accelerators, and often beyond the capacity of their hosts. Meanwhile, nonvolatile memory (NVM) storage has emerged as a pervasive component in HPC systems because NVM provides massive amounts of memory capacity at affordable cost. Currently, for accelerator applications to use NVM, they must manually orchestrate data movement across multiple memories and this approach only performs well for applications with simple access behaviors. To address this issue, we developed DRAGON, a solution that enables all classes of GP-GPU applications to transparently compute on terabyte datasets residing in NVM. DRAGON leverages the page-faulting mechanism on the recent NVIDIA GPUs by extending capabilities of CUDA Unified Memory (UM). Our experimental results show that DRAGON transparently expands memory capacity and obtain additional speedups via automated I/O and data transfer overlapping.
According to some embodiments, the present invention provides a novel photovoltaic solar cell system from photovoltaic modules that are vertically arrayed in a stack format using thin film semiconductors selected from among organic and inorganic thin film semiconductors. The stack cells may be cells that are produced in a planar manner, then vertically oriented in an angular form, also termed herein tilted, to maximize the light capturing aspects. The use of a stack configuration system as described herein allows for the use of a variety of electrode materials, such as transparent materials or semitransparent metals. Light concentration can be achieved by using fresnel lens, parabolic mirrors or derivatives of such structures. The light capturing can be controlled by being reflected back and forth in the photovoltaic system until significant quantities of the resonant light is absorbed. Light that passes to the very end and can be reflected back through the device by beveling or capping the end of the device with a different refractive index material, or alternatively using a reflective surface. The contacting between stacked cells can be done in series or parallel. According to some embodiments, the present invention uses a concentrator architecture where the light is channeled into the cells that contain thermal fluid channels (using a transparent fluid such as water) to absorb and hence reduce the thermal energy generation.
An aspect of the present disclosure is a device that includes a switchable material and an intercalating species, such that when a first condition is met, at least a portion of the intercalating species is associated with the switchable material and the switchable material is substantially transparent and substantially colorless, and when a second condition is met, at least a fraction of the portion of the intercalating species is transferred from the switchable material and the switchable material is substantially transparent and substantially colored.