Degraded visual environments are a serious concern for modern sensing and surveillance systems. Fog is of interest due to the frequency of its formation along our coastlines disrupting border security and surveillance. Fog presents hurdles in intelligence and reconnaissance by preventing data collection with optical systems for extended periods. We will present recent results from our work in operating optical systems in our controlled fog experimental chamber. This facility is a 180-foot-long, 10-foot-wide, and 10-foot-Tall structure that has over 60 spray nozzles to achieve uniform aerosol coverage with various particle size, distributions, and densities. We will discuss the physical formation of fog in nature and how our generated fog compares. In addition, we will discuss fog distributions and characterization techniques. We will investigate the biases of different methods and discuss the different techniques that are appropriate for realistic environments. Finally, we will compare the data obtained from our characterization studies against accepted models (e.g., MODTRAN) and validate the usage of this unique capability as a controlled experimental realization of natural fog formations. By proving the capability, we will enable the testing and validation of future fog penetrating optical systems and providing a platform for performing optical propagation experimentation in a known, stable, and controlled environment.
A sodium coolant accident analysis code is necessary to provide regulators with a means of performing confirmatory analyses for future sodium reactor licensing submissions. MELCOR and CONTAIN, which have been employed by the U.S. Nuclear Regulatory Commission for light water reactor licensing, have been traditionally used for Level 2 and Level 3 probabilistic analyses as well as containment design basis accident analysis. To meet future regulatory needs, new models are being added to the MELCOR code for simulation of sodium reactor designs by integrating the existing models developed for separate effects codes into the MELCOR architecture. Sodium properties and equations of state, such as from the SAS4A code, have previously been implemented into MELCOR to replace the water properties and equation of state. Additional specific sodium-related models to address design basis accidents are now being implemented into MELCOR from CONTAIN-LMR. Although the codes are very different in the code architecture, the feasibility fit is being investigated, and the models for the sodium spray fire and the sodium pool fire have been integrated into MELCOR. A new package called Sodium Chemistry (NAC) has been added to MELCOR to handle all sodium related chemistry models for sodium reactor safety applications. Although MELCOR code requires the ambient condition to be above the freezing point of the coolant (e.g., sodium or water), the high relative freezing point of sodium requires MELCOR to handle situations, particularly far from the primary circuit, where the ambient temperatures are usually at room temperature. Because only a single coolant can be modeled in a problem at a time, any presence of water in the problem would be treated as a trace material, an aerosol, in MELCOR. This paper addresses and describe the integration of the sodium models from CONTAIN-LMR, and the testing of the sodium chemistry models in the NAC package of MELCOR that handles sodium type reactor accidents, using available sodium experiments on spray fire and pool fire. In addition, we describe the anticipated sodium models to be completed in this year, such as the atmospheric chemistry model and sodiumconcrete interaction model. Code-to-code comparison between MELCOR and CONTAIN-LMR results, in addition to the experiment code validations, will be demonstrated in this year.
Children with autism spectrum disorders (ASD) and their unaffected siblings (US) are frequent targets of social bullying, which leads to severe physical, emotional, and social consequences. Understanding the risk factors is essential for developing preventative measures. We suggest that one such risk factor may be a difficulty to discriminate different biological body movements (BBM), a task that requires fast and flexible processing and interpretation of complex visual cues, especially during social interactions. Deficits in cognition of BBM have been reported in ASD. Since US display an autism endophenotype we expect that they will also display deficits in social interpretation of BBM. Methods. Participants: 8 US, 8 matched TD children, age 7-14; Tasks/Measurements: Social Blue Man Task: Narrative interpretation with a Latent Dirichlet Allocation [LDA] analysis; Social Experience Questionnaires with children and parents. Results. The US displayed as compared to TD: (i) low self-awareness of social bullying in contrast to high parental reports; (ii) reduced speed in identifying social cues; (iii) lower quality and repetitious wording in social interaction narratives (LDA). Conclusions. US demonstrate social endophenotype of autism reflected in delayed identification, interpretation and verbalization of social cues; these may constitute a high risk factor for becoming a victim of social bullying.
We present a new, non-destructive electrical technique, Power Spectrum Analysis (PSA). PSA as described here uses off-normal biasing, an unconventional way of powering microelectronics devices. PSA with off-normal biasing can be used to detect subtle differences between microelectronic devices. These differences, in many cases, cannot be detected by conventional electrical testing. In this paper, we highlight PSA applications related to aging and counterfeit detection.
ANS IHLRWM 2017 - 16th International High-Level Radioactive Waste Management Conference: Creating a Safe and Secure Energy Future for Generations to Come - Driving Toward Long-Term Storage and Disposal
Neodymium hydroxide, Nd(OH)3, solubility experiments were carried out in duplicate at room temperature over the pH interval of 10 to 13 for up to 670 days. The ionic radii of Nd(III) is similar to that of Pu(III) and Am(III), so that the former is an appropriate analog for the latter radionuclides. Average concentrations of Nd in solution approach a value of 2.0 × 10-7 mol/L and equilibrium concentrations show no dependence on solution pH. Compared to previous work, the data from this investigation form a continuum across pH-space, indicating agreement amongst data sets.
Recent Magnetized Liner Inertial Fusion experiments at the Sandia National Laboratories Z pulsed power facility have featured a PDV (Photonic Doppler Velocimetry) diagnostic in the final power feed section for measuring load current. In this paper, we report on an anomalous pressure that is detected on this PDV diagnostic very early in time during the current ramp. Early time load currents that are greater than both B-dot upstream current measurements and existing Z machine circuit models by at least 1 MA would be necessary to describe the measured early time velocity of the PDV flyer. This leads us to infer that the pressure producing the early time PDV flyer motion cannot be attributed to the magnetic pressure of the load current but rather to an anomalous pressure. Using the MHD code ALEGRA, we are able to compute a time-dependent anomalous pressure function, which when added to the magnetic pressure of the load current, yields simulated flyer velocities that are in excellent agreement with the PDV measurement. We also provide plausible explanations for what could be the origin of the anomalous pressure.
Distributed Energy Resources (DER) are being added to the nation's electric grid, and as penetration of these resources increases, they have the potential to displace or offset large-scale, capital-intensive, centralized generation. Integration of DER into operation of the traditional electric grid requires automated operational control and communication of DER elements, from system measurement to control hardware and software, in conjunction with a utility's existing automated and human-directed control of other portions of the system. Implementation of DER technologies suggests a number of gaps from both a security and a policy perspective.
We report a simple method to synthesize V 4+ (VO 2+ ) electrolytes as feedstock for all- vanadium redox flow batteries (RFB). By dissolving V 2 O 5 in aqueous HCl and H 2 SO 4 , subsequently adding glycerol as a reducing agent, we have demonstrated an inexpensive route for electrolyte synthesis to concentrations >2.5 M V 4+ (VO 2+ ). Electrochemical analysis and testing of laboratory scale RFB demonstrate improved thermal stability across a wider temperature range (-10-65 degC) for V 4+ (VO 2+ ) electrolytes in HCl compared to in H 2 SO 4 electrolytes.
The thermal degradation of two polyurethane elastomers was investigated via thermal gravimetric analysis coupled with gas chromatography/ma ss spectrometry. Decomposition occur s in a multi - step fashion with similar onset temperatures for both materials. Apparent activation energy plots were calculated inside Model - Free Kinetics software and utilized to construct conversion and isothermal conversion tables . These tables predicted material degradation as a function of temperature and time. Isothermal experiments were performed and found to be in good agreement with the predictions made from the Model - Free Kinetic s software package. Volatile products evolved during the multistep decomposition were captured at various times and analyzed using the coupled gas chromatography/mass spectrometry system . This analysis demonstrated strong correlation between the degradation products and known decomposition mechanisms for polyurethanes.
Since our last paper, cyber attacks have shown no evidence of declining in frequency or sophistication. We claim that applying isolation zones is an effective way to defend cyber systems; our team proposes a simulation and mathematical model that provide numerical data that supports this claim. This paper extends our earlier cyber zone defense (CZD) framework in two critical ways. First, we relax our assumption that zones completely isolate nodes and consider interzone boundaries to be porous. Second, we investigate methods to estimate one of the legacy parameters inherited from our earlier work and the new porosity parameter. The extended simulation and model more closely approximate real world cyber systems and have lower residuals than our previous investigation.
Silicon-based metal-oxide-semiconductor quantum dots are prominent candidates for high-fidelity, manufacturable qubits. Due to silicon's band structure, additional low-energy states persist in these devices, presenting both challenges and opportunities. Although the physics governing these valley states has been the subject of intense study, quantitative agreement between experiment and theory remains elusive. Here, we present data from an experiment probing the valley states of quantum dot devices and develop a theory that is in quantitative agreement with both this and a recently reported experiment. Through sampling millions of realistic cases of interface roughness, our method provides evidence that the valley physics between the two samples is essentially the same.
