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This report documents the development testing of a residential smart range hood for automated mitigation of air pollutants generated during cooking events.
This project explored the use of quantum-assisted algorithms for pattern matching in sub-atomic physics experiments. Pattern matching algorithms are commonly employed to prune data of random noise and to help discriminate between signals generated by particle tracks of interest and signals generated by background events. The quantum-assisted algorithms explored in this project were based on an Ising formulation of quantum associative model (QAMM) recall and quantum content-addressable memory (QCAM) recall. The recall is performed by comparing a probe pattern with those stored in a library of patterns encoded in the QAMM/QCAM model. The classification accuracy of QAMM and QCAM recall was determined as a function of detector resolution, noise, and efficiency and pattern density, where pattern density is defined as the ratio of the number of reference signal patterns encoded in the library to each pattern’s length. We found that QAMM achieved high classification accuracy when applied to datasets with low pattern density. QCAM achieved high classification accuracy for datasets with high pattern density and was found to be more robust to detector noise. The project methodology and results are described in detail in our arXiv preprint (arXiv:2011.11848) . This project was conducted by scientists at the Johns Hopkins University Applied Physics Laboratory and Oak Ridge National Laboratory from August 2018 to August 2020 and was supported by DOE grant DE-SC0019497.
All fission gas release data stored in the Fuels Irradiation & Physics Database (FIPD) was originally measured using the Gas Assay, Sample and Recharge (GASR) System in the Hot Fuel Examination Facility (HFEF). It is therefore called GASR data in FIPD. During the measurement of a sample, such as an irradiated EBR-II fuel element/capsule, a pinhole-sized region near the top of the element plenum was melted by a laser. Plenum gas then expanded into a calibrated volume (note: in this document, “sample” and “capsule/element” are used interchangeably consistent with GASR documents in FIPD). The pressure rise in the volume was recorded. Helium backfilling and expansion was then performed to determine the sample (e.g., fuel element plenum) volume using Boyle’s Law and assuming ideal gas behavior at constant temperature. With the plenum volume and the recorded pressure rise, the sample (e.g., fuel element plenum) pressure was derived with assumption of ideal gas law behavior. The plenum volume and pressure as well as the cladding temperature during the measurement were collected (GASR data in FIPD). Other records associated with the fission gas release data include: raw GASR data records including volumes and post-puncture pressures of seal head/sealing head and manifold, calibration data, backfilling gas pressure data, and the data analysis records. A sample(s) of the fission gas released from the plenum was collected by the GASR system into sample bottles. The chemical and isotopic composition of the gas sample was analyzed separately from GASR data, and will be discussed in a separate specification. The plenum volume, pressure, and cladding temperature during the measurement are typically utilized to determine the number of moles of gas in the plenum. This quantity is often compared to the number of moles of gas generated by fission events. However, calculating these values and their associated uncertainty is beyond the scope of this document, as it necessitates additional assumptions. The most important document to understand the FIPD fission gas data is the GASR operational manual (title: Gas Assay, Sample and Recharge System (GASR) operation and maintenance manual, HFEF/N OMM 4381, DOC. NO. W0018-0032-ES-00). This manual provides: (1) description of the GASR and the functions of each component (laser drilling, welding, seal head/sealing head, manifold, vacuum system, sample system, purge and gas tag system, etc.); (2) step-by-step guidance on calibrations, operations, and measurements; and (3) maintenance procedures and other details relating to the structure and operation of the GASR. Note that the original GASR operated until 2020. A new GASR with the same design and measurement methodology was installed in 2021. The specifications of the GASR presented on the HFEF website at this time are consistent with the ones given in the operational manual. The methods to calculate the plenum volume and pressures were not included in the operational manual, but were recorded in the legacy data analysis files. Details of the methods are given in Chapter 3.
The ICARUS T600 detector is the largest Liquid Argon Time Projection Chamber ever used on a neutrino beam, and it acts as the far detector of the Short Baseline Neutrino program at Fermilab. Its purpose is the study of the possibility of the existence of a fourth sterile neutrino in the O(eV2) mass range that could take part in the neutrino oscillations. The light detection system of the ICARUS detector plays the role of localising in space and time the neutrino interactions taking place inside the detector, collecting the argon scintillation photons generated when an event occurs. This light detection system also has a crucial role in the trigger system and the rejection of the huge amount of background cosmic events, working together with the trigger request signals sent by the beam complex. In August 2023 part of the cables that are used to carry the signals from the photomultipliers to the electronics were replaced with a new model, because a deterioration of the quality of the signal inside the cables had previously been observed. An analysis of the performance of the new cables was carried out, comparing laser run data collected before and after the change of the cable model, and it was proved that the introduction of the new cables lead to a general improvement of the quality of the signals reaching the electronics.
The current baseline method and software implementation of the space shuttle reaction control subsystem failure detection and identification (RCS FDI) system is presented. This algorithm is recommended for conclusion in the redundancy management (RM) module of the space shuttle guidance, navigation, and control system. Supporting software is presented, and recommended for inclusion in the system management (SM) and display and control (D&C) systems. RCS FDI uses data from sensors in the jets, in the manifold isolation valves, and in the RCS fuel and oxidizer storage tanks. A list of jet failures and fuel imbalance warnings is generated for use by the jet selection algorithm of the on-orbit and entry flight control systems, and to inform the crew and ground controllers of RCS failure status. Manifold isolation valve close commands are generated in the event of failed on or leaking jets to prevent loss of large quantities of RCS fuel.
In a computer simulation study of earthquakes a seismically active strike slip fault is represented by coupled mechanical blocks which are driven by a moving plate and which slide on a friction surface. Elastic forces and time independent friction are used to generate main shock events, while viscoelastic forces and time dependent friction add aftershock features. The study reveals that the size, length, and time and place of event occurrence are strongly influenced by the magnitude and degree of homogeneity in the elastic, viscous, and friction parameters of the fault region. For example, periodically reoccurring similar events are observed in simulations with near-homogeneous parameters along the fault, whereas seismic gaps are a common feature of simulations employing large variations in the fault parameters. The study also reveals correlations between strain energy release and fault length and average displacement and between main shock and aftershock displacements.
The output of a triggered avalanche mode avalanche photodiode is modeled as Poisson distributed primary avalanche events plus conditionally Poisson distributed trapped carrier induced secondary events. The moment generating function as well as the mean and variance of the diode output statistics are derived. The dispersion of the output statistics is shown to always exceed that of the Poisson distribution. Several examples are considered in detail.
Today's flight simulators, such as NASA's multimillion dollar Vertical Motion Simulator (VMS), recreate an authentic aircraft environment, and reproduce the sensations of flight by mechanically generating true physical events. In addition to their application as a training tool for pilots, simulators have become essential in the design, construction, and testing of new aircraft. Simulators allow engineers to study an aircraft's flight performance and characteristics without the cost or risk of an actual test flight. Because of their practicality, simulators will become more and more important in the development and design of new, safer aircraft.
Dayside magnetic reconnection was studied by using a three-dimensional global magnetohydrodynamic simulation of the interaction between the solar wind and the magnetosphere. Two different mechanisms were found for the formation of magnetic flux tubes at the dayside magnetopause, which depend on the orientation of the interplanetary magnetic field (IMF). The dayside magnetic flux tubes occur only when the IMF has a southward component. A strongly twisted and localized magnetic flux tube similar to magnetic flux ropes appears at the subsolar magnetopause when the IMF has a large B(y) component. When the B(y) component is small, twin flux tubes appear at the dayside magnetopause. Both types of magnetic flux tube are consistent with several observational features of flux transfer events and are generated by antiparallel magnetic reconnection.
Passive microwave images from the Special Sensor Microwave Imager are used to study the volume of ice and sea-bottom water in the Japan Sea as affected by winds and severe storms. The data set comprises brightness temperatures gridded on a polar stereographic projection, and the processing is accomplished with a linear algorithm by Cavalieri et al. (1983) based on the vertically polarized 37-GHz channel. The expressions for calculating heat fluxes and downwelling radiation are given, and ice-cover fluctuations are correlated with severe storm events. The storms generate large transient polynya that occur simultaneously with the strongest heat fluxes, and severe storms are found to contribute about 25 percent of the annual introduction of 25 cu km of ice in the region. The ice production could lead to the renewal of enough sea-bottom water to account for the C-14 data provided, and the generation of Japan Sea bottom water is found to vary directly with storm activity.
Observations of the IMF carried out from October 1990 to February 1992 during the in-ecliptic phase of the Ulysses mission are presented. The observations were made between 1 and 5.4 AU during a different phase of the solar cycle from previous missions. The large-scale reorganization of the solar coronal fields following the maximum in Solar Cycle 22 generated numerous transient events, causing large-scale disturbances in interplanetary space, particularly during the first half of 1991. From about the middle of 1991, solar activity apparently decreased, resulting in fewer transient events, allowing the formation of corotating interaction regions (CIRs) recurring in successive solar rotations. Observations of the IMF reflect this temporal evolution in solar activity. However, the average orientation of the IMF, the observed sector structure, and the evolution of the CIRs show that the dynamic interaction of transient events with evolving stream-stream structures in this heliocentric distance range results in significant deviations from the expected IMF topology, even when signature of the transients is less apparent.
Few contest that mass extinctions have punctuated the history of life, or that those events were so pervasive environmentally, taxonomically, and geographically that physical forcing factors were probably involved. However, consensus remains elusive on the nature of those factors, and on how a given perturbation - impact, volcanism, sea-level change, or ocean anoxic event - could actually generate the observed intensity and selectivity of biotic losses. At least two basic problems underlie these long-standing disagreements: difficulties in resolving the fine details of taxon ranges and abundances immediately prior to and after an extinction boundary and the scarcity of simple, unitary cause-and-effect relations in complex biological systems.
The catastrophic Chicxulub event should have generated a large hydrothermal system with volatile element mobilization, producing interesting alteration materials and clays. The Yaxcopoil-1 (YAX) drill hole is located in the annular trough, about 70 km southwest of the crater center, in an area where the impactite layers are relatively thin (approx. 100 m thick). We have analyzed samples from the YAX drill core and from other impact craters including Mistastin and Lonar to determine the nature of alteration and trace element mobilization.
Mars is the most Earth-like of the Solar System s planets, and the first place to look for any sign of present or past extraterrestrial life. Its surface shows many features indicative of the presence of surface and sub-surface water, while impact cratering and volcanism have provided temporary and local surface heat sources throughout Mars geologic history. Impact craters are widely used ubiquitous indicators for the presence of sub-surface water or ice on Mars. In particular, the presence of significant amounts of ground ice or water would cause impact-induced hydrothermal alteration at Martian impact sites. The realization that hydrothermal systems are possible sites for the origin and early evolution of life on Earth has given rise to the hypothesis that hydrothermal systems may have had the same role on Mars. Rough estimates of the heat generated in impact events have been based on scaling relations, or thermal data based on terrestrial impacts on crystalline basements. Preliminary studies also suggest that melt sheets and target uplift are equally important heat sources for the development of a hydrothermal system, while its lifetime depends on the volume and cooling rate of the heat source, as well as the permeability of the host rocks. We present initial results of two-dimensional (2D) and three-dimensional (3D) simulations of impacts on Mars aimed at constraining the initial conditions for modeling the onset and evolution of a hydrothermal system on the red planet. Simulations of the early stages of impact cratering provide an estimate of the amount of shock melting and the pressure-temperature distribution in the target caused by various impacts on the Martian surface. Modeling of the late stage of crater collapse is necessary to characterize the final thermal state of the target, including crater uplift, and distribution of the heated target material (including the melt pool) and hot ejecta around the crater.
The Georges Creek watershed (area 187.5 sq km) in western Maryland (United States) has experienced land use changes (>17% of area) associated with surface mining of coal. The adjacent Savage River watershed (area 127.2 sq km) is unmined. Moments of flood frequency distributions indicated that climatic variability affected both watersheds similarly. Normalizing annual maximum flows by antecedent streamflow and causative precipitation helped identify trends in flooding response. Analysis of contemporary storm events using Next Generation Weather Radar (NEXRAD) stage III precipitation data showed that Georges Creek floods are characterized by higher peak runoff and a shorter centroid lag than Savage River floods, likely attributable to differences in current land use. Interestingly, Georges Creek produces only two thirds of the storm-flow volume as Savage River, apparently because of infiltration into abandoned deep mine workings and an associated transbasin diversion constructed circa 1900. Empirical trend analysis is thus complicated by both hydroclimatic variability and the legacy of deep mining in the basin.
As the Mars Relay Network is in constant flux (missions and teams going through their daily workflow), it is imperative that users are aware of such state changes. For example, a change by an orbiter team can affect operations on a lander team. This software provides an ambient view of the real-time status of the Mars network. The Mars Relay Operations Service (MaROS) comprises a number of tools to coordinate, plan, and visualize various aspects of the Mars Relay Network. As part of MaROS, a feature set was developed that operates on several levels of the software architecture. These levels include a Web-based user interface, a back-end "ReSTlet" built in Java, and databases that store the data as it is received from the network. The result is a real-time event notification and management system, so mission teams can track and act upon events on a moment-by-moment basis. This software retrieves events from MaROS and displays them to the end user. Updates happen in real time, i.e., messages are pushed to the user while logged into the system, and queued when the user is not online for later viewing. The software does not do away with the email notifications, but augments them with in-line notifications. Further, this software expands the events that can generate a notification, and allows user-generated notifications. Existing software sends a smaller subset of mission-generated notifications via email. A common complaint of users was that the system-generated e-mails often "get lost" with other e-mail that comes in. This software allows for an expanded set (including user-generated) of notifications displayed in-line of the program. By separating notifications, this can improve a user's workflow.
Igneous rocks are the primary building blocks of planetary crusts. Most igneous rocks originate via decompression melting and/or wet melting of protolith lithologies within planetary interiors and their classification and compositional, petrographic, and textural characteristics, arewell-studied. As our exploration of the Solar System continues, so too does the inventory of intrusive and extrusive igneous rocks, settings, and processes. The results of planetary exploration have also clearly demonstrated that impact cratering is a ubiquitous geological process that has affected, andwill continue to affect, all planetary objectswith a solid surface,whether that be rock or ice. It is nowrecognized that the production of igneous rocks is a fundamental outcome of hypervelocity impact. The goal of this review is to provide an up-to-date synthesis of our knowledge and understanding of igneous rocks formed by hypervelocity impact. Following a brief overview of the basics of the impact process, we describe howand whymelts are generated during impact events and howimpactmelting differs fromendogenic igneous processes.While the processmay differ,we showthat the products of hypervelocity impact can share close similarities with volcanic and shallow intrusive igneous rocks of endogenic origin. Such impact melt rocks, as they are termed, can display lobate margins and cooling cracks, columnar joints and at the hand specimen andmicroscopic scale, such rocks can displaymineral textures that are typical of volcanic rocks, such as quench crystallites, ophitic, porphyritic, aswell as features such as vesicles, flowtextures, and so on.Historically, these similarities led to themisidentification of some igneous rocks now known to be impact melt rocks as being of endogenic origin. This raises the question as to how to distinguish between an impact versus an endogenic origin for igneous-like rocks on other planetary bodies where fieldwork and sample analysis may not be possible and all that may be available is remote sensing data.While the interpretation of some impact melt rocks may be relatively straightforward (e.g., for clast-rich varieties and those with clear projectile contamination) we conclude that distinguishing between impact and endogenic igneous rocks is a non-trivial task that ultimately may require sample investigation and analysis to be conducted. Caution is, therefore, urged in the interpretation of igneous rocks on planetary surfaces.
In June 2019, a full-scale crash test of a Fokker F28 Fellowship aircraft will be conducted at NASA Langley Research Center?s Landing and Impact Research (LandIR) Facility. The F28 is a high-performance twin-turbo fan narrow-body aircraft with seating in a 3+2 configuration. The MK4000 variant, used in this test, is capable of carrying up to 85 passengers on medium range routes. The F28 was first type certified by the Federal Aviation Administration (FAA) in 1969 and now the majority of the F28 fleet has retired from service in the United States. In 2016, the FAA and NASA Langley Research Center (LaRC) signed an interagency agreement for conducting a research program to obtain test data that will support the development of airframe level crash requirements for transport category airplanes [1]. The objectives of the full-scale crash test can be divided into six categories: (1) To compare and contrast responses in identical aircraft undergoing vertical only to combined vertical and horizontal loading conditions, (2) To examine the effects of horizontal loading on aircraft structure during a crash event, (3) To generate data for the use in calibration of computer modelling efforts, (4) To generate data from onboard Anthropomorphic Test Devices (ATDs) for the evaluation of injury, (5) To obtain data from experimental seats, and (6) To obtain data from new and novel ATD designs including Warrior Injury Assessment MANikin (WIAMan) [2], Test device for Human Occupant Response (THOR), and other newly developed child ATDs. The focus of this presentation will be to document finite element model development of the full-scale F28 aircraft and to present preliminary test-analysis predictions. NASA obtained the full-scale F28 aircraft, plus three fuselage sections and two sets of wings with funding through the NASA Aviation Safety Program in 1998. In addition to the hardware, NASA purchased a full NASTRAN model of the airframe that had been developed by the Dutch manufacturer, Fokker. Beginning in 2016, the NASTRAN model was converted to LS-DYNA? [4, 5] format and modified by combining parts, adding missing parts of internal structure, and including ballast for loading weights, etc. It contains: 89,223 nodes; 24,065 beam elements; 55,404 shell elements; 29,044 solid elements; 740 parts; 80 material definitions; and, 46 Constrained Nodal Rigid Bodies (CNRBs). The aircraft model will be executed in LSDYNA to simulate the test article impact onto a 2-ft.-high bed of soil under combined velocity conditions of 70-ft/s forward and 30-ft/s vertical velocity. Pre-test simulation predictions will be generated and correlated with test data.