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At least 1,243 records · Page 69

Using Best Basis Inventory Data to Direct Strategies for Real Time Monitoring of Hanford High Level Waste – 26226

The potential to accelerate the processing of low- and high-level tank waste by applying real-time monitoring (RTM) of chemical and physical properties has prompted research into the suitability of multiple analytical methods for that purpose. The broad variety of waste stream properties and the large number of analytes of interest (as evidenced by Waste Acceptance Criteria (WAC) and Process Control Limit (PCL) lists) lead to an overwhelming set of possible analytical scenarios. This report describes the use of Best Basis Inventory (BBI) data to find the most relevant analytical targets for the specific case of monitoring the blending of High Level Waste from multiple tanks prior to introduction into a vitrification facility. Campaigns for blending this waste to minimize the risk of exceeding WACs and PCLs have been proposed. However, the predicted compositions of the blended materials do not incorporate any uncertainties that may be associated with the representativeness of the waste layer samples or the laboratory analyses that generated the BBI data. Also, they do not include any uncertainty associated with the precision of collecting highly specific fractions of the layers during a blending campaign or any inhomogeneities that may exist in those layers. Monte Carlo methods are used to apply uncertainties to the compositions of the individual layers specified in the campaign recipes. The resulting variations in the compositions of the blended materials allow estimation of the risks of exceeding WACs and PCLs for each campaign. A critical subset of WACs/PCLs – NOx, NaK, AlFeZr, and S – are especially at risk of being exceeded in multiple campaigns. These analytes should be the focus of instrument development. We also have extracted the expected solid/supernate distribution for these analytes, which establishes important performance criteria for individual analytical methods. The BBI data also permits an understanding of the different chemical forms in which the analytes appear. Thus, the need to establish instrumental sensitivity to these forms can be gainfully addressed. Although concentrating on one specific application – the blending of tank waste - this approach should be generalizable for the analysis of other possible RTM applications for waste processing.

Lascola, Robert [Savannah River National Laborator↗

TESTING OF THE SECOND GENERATION SPINTEK ROTARY FILTER -11357

The SpinTek rotary microfilter has been developed under the Department of Energy (DOE) Office of Environmental Management (EM) for the purpose of deployment in radioactive service in the DOE complex. The unit that was fabricated and tested is the second generation of the filter that incorporates recommended improvements from previous testing. The completion of this test satisfied a key milestone for the EM technology development program and technology readiness for deployment by Savannah River Remediation in the Small Column Ion Exchange and Sludge Washing processes at the Savannah River Site (SRS). The Savannah River National Laboratory (SRNL) contracted SpinTek Filtration to fabricate a full scale 25 disk rotary filter and perform a 1000 hour endurance test with a simulated SRS sludge. Over 1500 hours of operation have been completed with the filter. SpinTek Filtration fabricated a prototypic 25 disk rotary filter including updates to manufacturing tolerances, an updated design to the rotary joint, improved cooling to the bottom journal, decreases in disk and filter shaft hydraulic resistances. The filter disks were fabricated with 0.5 {micro} pore size, sintered-metal filter media manufactured by Pall Corporation (M050). After fabrication was complete, the filter passed acceptance tests demonstrating rejection of solids and clean water flux with a 50% improvement over the previous filters. Once the acceptance test was complete, a 1000 hour endurance test was initiated simulating a sludge washing process. The test used a simulated SRS Sludge Batch 6 recipe. The insoluble solids started at 5 wt% and were raised to 10 and 15 wt% insoluble solids to simulate the concentration of a large volume tank. The filter system was automated and set up for 24 hour unattended operation. To facilitate this, process control logic was written to operate the filter. During the development it was demonstrated that the method of starting and stopping the filter can affect the build up of filter cake on the disks and therefore the performance of the filter. The filter performed well with the simulant. Very little drop in production was noticed between the 5 and 10 wt% insoluble solids feed. Increasing to 15 wt% had a more pronounced impact due to the rheology of the feed. Acid cleaning was used to clean the filter disks in-situ and restore filtration rate to almost 90% of the initial clean disk rate. Eighty liters of 0.2 M nitric acid in conjunction with water rinses were used to clean the filter in less than 2 hours. Filter testing was completed after 1000 hours of operation were performed on the final filter assembly configuration. The total run time for the testing was over 1500 hours. At the end of the test, the sludge washing was performed successfully from approximately 5.6 M to less than 1 M sodium.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Reverse micelles directed synthesis of TiO{sub 2}-CeO{sub 2} mixed oxides and investigation of their crystal structure and morphology

The synthesis of TiO{sub 2}-CeO{sub 2} mixed oxides based on the sol-gel process controlled within reverse micelles of non-ionic surfactant Triton X-114 in cyclohexane is reported. The crystallization, phase composition, trends in nanoparticles growth and porous structure properties are studied as a function of Ti:Ce molar composition and annealing temperature by in-situ X-ray diffraction, Raman spectroscopy and physisorption. The brannerite-type CeTi{sub 2}O{sub 6} crystallizes as a single crystalline phase at Ti:Ce molar composition of 70:30 and in the mixture with cubic CeO{sub 2} and anatase TiO{sub 2} for composition 50:50. At Ti:Ce molar ratios 90:10 and 30:70 the mixtures of TiO{sub 2} anatase, rutile and cubic CeO{sub 2} appear. In these mixtures TiO{sub 2} rutile is formed at higher temperatures than conventionally. Additionally, the amount of a present amorphous phase in individual mixtures was estimated from diffraction data. The porous structure morphology depends both on molar composition and annealing temperature. This is correlated with the presence of carbon impurities of different character. - Graphical abstract: The phase composition of Ti90--Ce10 and Ti50--Ce50 oxide mixtures as a function of annealing temperature. The amount of the amorphous phase was estimated and attributed to TiO{sub 2}. Highlights: Black-Right-Pointing-Pointer Ti/Ce oxides were prepared using reverse micelles of Triton X-114. Black-Right-Pointing-Pointer Crystallization of TiO{sub 2}, CeO{sub 2} or CeTi{sub 2}O{sub 6} depends on Ti:Ce molar ratio. Black-Right-Pointing-Pointer Amorphous phase attributed to TiO{sub 2} was identified. Black-Right-Pointing-Pointer Metal oxides surface area is influenced by the character of present carbon impurities.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

EVALUATION OF THE IMPACT OF THE DEFENSE WASTE PROCESSING FACILITY (DWPF) LABORATORY GERMANIUM OXIDE USE ON RECYCLE TRANSFERS TO THE H-TANK FARM

When processing High Level Waste (HLW) glass, the Defense Waste Processing Facility (DWPF) cannot wait until the melt or waste glass has been made to assess its acceptability, since by then no further changes to the glass composition and acceptability are possible. Therefore, the acceptability decision is made on the upstream feed stream, rather than on the downstream melt or glass product. This strategy is known as 'feed forward statistical process control.' The DWPF depends on chemical analysis of the feed streams from the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) where the frit plus adjusted sludge from the SRAT are mixed. The SME is the last vessel in which any chemical adjustments or frit additions can be made. Once the analyses of the SME product are deemed acceptable, the SME product is transferred to the Melter Feed Tank (MFT) and onto the melter. The SRAT and SME analyses have been analyzed by the DWPF laboratory using a 'Cold Chemical' method but this dissolution did not adequately dissolve all the elemental components. A new dissolution method which fuses the SRAT or SME product with cesium nitrate (CsNO{sub 3}), germanium (IV) oxide (GeO{sub 2}) and cesium carbonate (Cs{sub 2}CO{sub 3}) into a cesium germanate glass at 1050 C in platinum crucibles has been developed. Once the germanium glass is formed in that fusion, it is readily dissolved by concentrated nitric acid (about 1M) to solubilize all the elements in the SRAT and/or SME product for elemental analysis. When the chemical analyses are completed the acidic cesium-germanate solution is transferred from the DWPF analytic laboratory to the Recycle Collection Tank (RCT) where the pH is increased to {approx}12 M to be released back to the tank farm and the 2H evaporator. Therefore, about 2.5 kg/yr of GeO{sub 2}/year will be diluted into 1.4 million gallons of recycle. This 2.5 kg/yr of GeO{sub 2} may increase to 4 kg/yr when improvements are implemented to attain an annual canister production goal of 400 canisters. Since no Waste Acceptance Criteria (WAC) exists for germanium in the Tank Farm, the Effluent Treatment Project, or the Saltstone Production Facility, DWPF has requested an evaluation of the fate of the germanium in the caustic environment of the RCT, the 2H evaporator, and the tank farm. This report evaluates the effect of the addition of germanium to the tank farm based on: (1) the large dilution of Ge in the RCT and tank farm; (2) the solubility of germanium in caustic solutions (pH 12-13); (3) the potential of germanium to precipitate as germanium sodalites in the 2H Evaporator; and (4) the potential of germanium compounds to precipitate in the evaporator feed tank. This study concludes that the impacts of transferring up to 4 kg/yr germanium to the RCT (and subsequently the 2H evaporator feed tank and the 2H evaporator) results in <2 ppm per year (1.834 mg/L) which is the maximum instantaneous concentration expected from DWPF. This concentration is insignificant as most sodium germanates are soluble at the high pH of the feed tank and evaporator solutions. Even if sodium aluminosilicates form in the 2H evaporator, the Ge will likely substitute for some small amount of the Si in these structures and will be insignificant. It is recommended that the DWPF continue with their strategy to add germanium as a laboratory chemical to Attachment 8.2 of the DWPF Waste Compliance Plan (WCP).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Improved simulation of extreme precipitation in a high-resolution atmosphere model

Climate models often underestimate the magnitude of extreme precipitation. We compare the performance of a high-resolution (~0.25°) time-slice atmospheric simulation (1979–2005) of the Community Earth System Model 1.0 in representing daily extreme precipitation events against those of the same model at lower resolutions (~1° and 2°). We find significant increases in the simulated levels of daily extreme precipitation over Europe, the United States, and Australia. In many cases the increase in high percentiles (>95th) of daily precipitation leads to better agreement with observational data sets. For lower percentiles, we find that increasing resolution does not significantly increase values of simulated precipitation. We argue that the reduced biases mainly result from the higher resolution models resolving more key physical processes controlling heavy precipitation. Lastly, we conclude that while high resolution is vital for accurately simulating extreme precipitation, considerable biases remain at the highest available model resolutions.

54 ENVIRONMENTAL SCIENCES↗

Intercomparison of Large-eddy Simulations of Arctic Mixed-phase Clouds: Importance of Ice Size Distribution Assumptions

Large-eddy simulations of mixed-phase Arctic clouds by 11 different models are analyzed with the goal of improving understanding and model representation of processes controlling the evolution of these clouds. In a case based on observations from the Indirect and Semi-Direct Aerosol Campaign (ISDAC), it is found that ice number concentration, Ni, exerts significant influence on the cloud structure. Increasing Ni leads to a substantial reduction in liquid water path (LWP) and potential cloud dissipation, in agreement with earlier studies. By comparing simulations with the same microphysics coupled to different dynamical cores as well as the same dynamics coupled to different microphysics schemes, it is found that the ice water path (IWP) is mainly controlled by ice microphysics, while the inter-model differences in LWP are largely driven by physics and numerics of the dynamical cores. In contrast to previous intercomparisons, all models here use the same ice particle properties (i.e., mass-size, mass-fall speed, and mass-capacitance relationships) and a common radiation parameterization. The constrained setup exposes the importance of ice particle size distributions (PSD) in influencing cloud evolution. A clear separation in LWP and IWP predicted by models with bin and bulk microphysical treatments is documented and attributed primarily to the assumed shape of ice PSD used in bulk schemes. Compared to the bin schemes that explicitly predict the PSD, schemes assuming exponential ice PSD underestimate ice growth by vapor deposition and overestimate mass-weighted fall speed leading to an underprediction of IWP by a factor of two in the considered case.

Arctic↗

Analytical approximation of transit time scattering due to magnetosonic waves

Abstract Recent test particle simulations have shown that energetic electrons traveling through fast magnetosonic (MS) wave packets can experience an effect which is specifically associated with the tight equatorial confinement of these waves, known as transit time scattering. However, such test particle simulations can be computationally cumbersome and offer limited insight into the dominant physical processes controlling the wave‐particle interactions, that is, in determining the effects of the various wave parameters and equatorial confinement on the particle scattering. In this paper, we show that such nonresonant effects can be effectively captured with a straightforward analytical treatment that is made possible with a set of reasonable, simplifying assumptions. It is shown that the effect of the wave confinement, which is not captured by the standard quasi‐linear theory approach, acts in such a way as to broaden the range of particle energies and pitch angles that can effectively resonate with the wave. The resulting diffusion coefficients can be readily incorporated into global diffusion models in order to test the effects of transit time scattering on the dynamical evolution of radiation belt fluxes.

Bortnik, J.↗

Measuring the seeds of ion outflow: auroral sounding rocket observations of low-altitude ion heating and circulation

Here, we present an analysis of in situ measurements from the MICA (Magnetosphere-Ionosphere Coupling in the Alfvén Resonator) nightside auroral sounding rocket with comparisons to a multifluid ionospheric model. MICA made observations at altitudes below 325 km of the thermal ion kinetic particle distributions that are the origins of ion outflow. Late flight, in the vicinity of an auroral arc, we observe frictional processes controlling the ion temperature. Upflow of these cold ions is attributed to either the ambipolar field resulting from the heated electrons or possibly to ion-neutral collisions. We measure E → xB → convection away from the arc (poleward) and downflows of hundreds of m s -1 poleward of this arc, indicating small-scale low-altitude plasma circulation. In the early flight we observe DC electromagnetic Poynting flux and associated ELF wave activity influencing the thermal ion temperature in regions of Alfvénic aurora. We observe enhanced, anisotropic ion temperatures which we conjecture are caused by transverse heating by wave-particle interactions (WPI) even at these low altitudes. Throughout this region we observe several hundred m s -1 upflow of the bulk thermal ions colocated with WPI; however, the mirror force is negligible at these low energies; thus, the upflow is attributed to ambipolar fields (or possibly neutral upwelling drivers). Moreover, the low-altitude MICA observations serve to inform future ionospheric modeling and simulations of (a) the need to consider the effects of heating by WPI at altitudes lower than previously considered viable and (b) the occurrence of structured and localized upflows/downflows below where higher-altitude heating rocesses are expected.

47 OTHER INSTRUMENTATION↗

The emergence of hydrogeophysics for improved understanding of subsurface processes over multiple scales

Geophysics provides a multidimensional suite of investigative methods that are transforming our ability to see into the very fabric of the subsurface environment, and monitor the dynamics of its fluids and the biogeochemical reactions that occur within it. Here we document how geophysical methods have emerged as valuable tools for investigating shallow subsurface processes over the past two decades and offer a vision for future developments relevant to hydrology and also ecosystem science. The field of “hydrogeophysics” arose in the late 1990s, prompted, in part, by the wealth of studies on stochastic subsurface hydrology that argued for better field-based investigative techniques. These new hydrogeophysical approaches benefited from the emergence of practical and robust data inversion techniques, in many cases with a view to quantify shallow subsurface heterogeneity and the associated dynamics of subsurface fluids. Furthermore, the need for quantitative characterization stimulated a wealth of new investigations into petrophysical relationships that link hydrologically relevant properties to measurable geophysical parameters. Development of time-lapse approaches provided a new suite of tools for hydrological investigation, enhanced further with the realization that some geophysical properties may be sensitive to biogeochemical transformations in the subsurface environment, thus opening up the new field of “biogeophysics.” Early hydrogeophysical studies often concentrated on relatively small “plot-scale” experiments. More recently, however, the translation to larger-scale characterization has been the focus of a number of studies. In conclusion, geophysical technologies continue to develop, driven, in part, by the increasing need to understand and quantify key processes controlling sustainable water resources and ecosystem services.

58 GEOSCIENCES↗

Terrestrial ecosystem model performance in simulating productivity and its vulnerability to climate change in the northern permafrost region: Modeled Productivity in Permafrost Regions

Realistic projection of future climate-carbon (C) cycle feedbacks requires better understanding and an improved representation of the C cycle in permafrost regions in the current generation of Earth system models. Here we evaluated 10 terrestrial ecosystem models for their estimates of net primary productivity (NPP) and responses to historical climate change in permafrost regions in the Northern Hemisphere. In comparison with the satellite estimate from the Moderate Resolution Imaging Spectroradiometer (MODIS; 246 ± 6 g C m -2 yr -1 ), most models produced higher NPP (309 ± 12 g C m -2 yr -1 ) over the permafrost region during 2000–2009. By comparing the simulated gross primary productivity (GPP) with a flux tower-based database, we found that although mean GPP among the models was only overestimated by 10% over 1982–2009, there was a twofold discrepancy among models (380 to 800 g C m -2 yr -1 ), which mainly resulted from differences in simulated maximum monthly GPP (GPP max ). Most models overestimated C use efficiency (CUE) as compared to observations at both regional and site levels. Further analysis shows that model variability of GPP and CUE are nonlinearly correlated to variability in specific leaf area and the maximum rate of carboxylation by the enzyme Rubisco at 25°C (Vc max_25 ), respectively. The models also varied in their sensitivities of NPP, GPP, and CUE to historical changes in climate and atmospheric CO 2 concentration. In conclusion, these results indicate that model predictive ability of the C cycle in permafrost regions can be improved by better representation of the processes controlling CUE and GPP max as well as their sensitivity to climate change.

54 ENVIRONMENTAL SCIENCES↗

Sources of methane to an Arctic lake in Alaska: An isotopic investigation

Sources of dissolved methane (CH 4 ) at Toolik Lake, Alaska, include both diffusion from lake sediments and groundwater entering the lake from its perimeter. Here we use hydrogen and oxygen isotopes in water (H 2 O), carbon and hydrogen isotopes in CH 4 , and carbon isotopes in dissolved inorganic carbon (DIC) to calculate the relative importance of lake sediment and groundwater discharge as sources of dissolved CH 4 to Toolik Lake. We also resolve the relative importance of the source contribution spatially within the lake and determine the processes controlling CH 4 concentrations in groundwater surrounding the lake. Our findings, from a mixing model based on isotopes in CH 4 , suggest that groundwater is a more important source of CH 4 at the perimeter of the lake where the water-to-air flux is high. In addition, we find on the local scale that high groundwater methane concentrations may be better linked to areas around the lake where rain is the dominant source of water to the active layer, indicating that changes in precipitation and active layer thaw depth will impact methane concentrations in the active layer and, ultimately, the groundwater associated flux to Toolik Lake.

54 ENVIRONMENTAL SCIENCES↗

Relativistic electron dynamics produced by azimuthally localized poloidal mode ULF waves: Boomerang-shaped pitch angle evolutions

Here, we present an analysis of “boomerang-shaped” pitch angle evolutions of outer radiation belt relativistic electrons observed by the Van Allen Probes after the passage of an interplanetary shock on 7 June 2014. The flux at different pitch angles is modulated by Pc5 waves, with equatorially mirroring electrons reaching the satellite first. For 90° pitch angle electrons, the phase change of the flux modulations across energy exceeds 180° and increasingly tilts with time. Using estimates of the arrival time of particles of different pitch angles at the spacecraft location, a scenario is investigated in which shock-induced ULF waves interact with electrons through the drift resonance mechanism in a localized region westward of the spacecraft. Numerical calculations on particle energy gain with the modified ULF wavefield reproduce the observed boomerang stripes and modulations in the electron energy spectrogram. The study of boomerang stripes and their relationship to drift resonance taking place at a location different from the observation point adds new understanding of the processes controlling the dynamics of the outer radiation belt.

58 GEOSCIENCES↗

Aluminum Tailor-Welded Blanks for High Volume Automotive Applications

A Design of Experiment based approach is used to systematically investigate relationships between 8 different welding factors (4 related to tool geometry, 4 related to weld process control) and resulting weld properties including strength, elongation and formability in 1.2mm-2mm thick friction stir welding of AA5182-O for TWB application. The factors that result in most significant effects are elucidated. The interactions between several key factors like plunge depth, tool tilt, pin feature and pin length on the overall weld quality is discussed. Appropriate levels of factors that lead to excellent weld properties are also identified.

Aluminum↗

Radiation‐Resistant Aluminum Alloy for Space Missions in the Extreme Environment of the Solar System

Future human exploration of the solar system demands advanced materials capable of withstanding extreme environments, particularly exposure to solar energetic particle radiation. Current material selection criteria for space applications prioritize a high strength-to-weight ratio, high corrosion resistance and manufacturability, favoring age-hardenable Al-based alloys. However, conventional precipitation-hardened Al alloys suffer from irradiation-assisted dissolution of strengthening phases at doses as low as 0.2 displacements-per-atom (dpa), undermining their performance. Furthermore, these alloys develop radiation-induced defects, such as dislocation loops and voids, even at low doses. This study presents a novel ultrafine-grained (UFG) Al-based alloy, designed using the crossover alloying concept and strengthened by T-phase precipitates, featuring a chemically-complex structure with 162 atoms in its unit cell composed of Mg 32 (Zn,Al) 49 . It is showed that T-phase precipitates have exceptional radiation tolerance up to 24 dpa. Owing to the nanoscale UFG structure, dislocation loops are suppressed, and voids are only observed beyond 75 dpa. Microtensile tests up to 20 dpa confirm the preservation of mechanical performance under irradiation. The results underline the potential of this alloy as a radiation-resistant, lightweight material for future space applications. Three key strategies enable this performance: (i) stabilization of a UFG microstructure, (ii) T-phase precipitation featuring a highly negative Gibbs free energy and chemically-complex giant unit cell, and (iii) precise process control to prevent grain growth during heat treatment and irradiation.

36 MATERIALS SCIENCE↗

Defining Golden Batches in Biomanufacturing Processes From Internal Metabolic Activity to Detect Process Changes That May Affect Product Quality

ABSTRACT Cellular metabolism plays a role in the observed variability of a drug substance's Critical Quality Attributes (CQAs) made by biomanufacturing processes. Therefore, here we describe a new approach for monitoring biomanufacturing processes that measures a set of metabolic reaction rates (named Critical Metabolic Parameters (CMP) in addition to the macroscopic process conditions currently being used as Critical Process Parameters (CPP) for biomanufacturing. Constraint‐based systems biology models like Flux Balance Analysis (FBA) are used to estimate metabolic reaction rates, and metabolic rates are used as inputs for multivariate Batch Evolution Models (BEM). Metabolic activity was reproducible among batches and could be monitored to detect a deliberately induced macroscopic process shift (i.e., temperature change). The CMP approach has the potential to enable “golden batches” in biomanufacturing processes to be defined from the internal metabolic activity and to aid in detecting process changes that may impact the quality of the product. Overall, the data suggested that monitoring of metabolic activity has promise for biomanufacturing process control.

Biotechnology & Applied Microbiology↗

Impact of media and antifoam selection on monoclonal antibody production and quality using a high throughput micro-bioreactor system

Monoclonal antibody production in commercial scale cell culture bioprocessing requires a thorough understanding of the engineering process and components used throughout manufacturing. It is important to identify high impact components early on during the lifecycle of a biotechnology-derived product. While cell culture media selection is of obvious importance to the health and productivity of mammalian bioreactor operations, other components such as antifoam selection can also play an important role in bioreactor cell culture. Silicone polymer-based antifoams were known to have negative impacts on cell health, production, and downstream filtration and purification operations. High throughput screening in micro-scale bioreactors provides an efficient strategy to identify initial operating parameters. Here, we utilized a micro-scale parallel bioreactor system to study an IgG1 producing CHO cell line, to screen Dynamis, ProCHO5, PowerCHO2, EX-Cell Advanced, and OptiCHO media, and 204, C, EX-Cell, SE-15, and Y-30 antifoams and their impacts on IgG1 production, cell growth, aggregation, and process control. This study found ProCHO5, EX-Cell Advanced, and PowerCHO2 media supported strong cellular growth profiles, with an IVCD of 25-35 3 106 cells-d/ mL, while maintaining specific antibody production (Qp> 2 pg/cell-d) for our model cell line and a monomer percentage above 94%. Antifoams C, EX-Cell, and SE-15 were capable of providing adequate control of foaming while antifoam 204 and Y-30 noticeably stunted cellular growth. This work highlights the utility of high throughput micro bioreactors and the importance of identifying both positive and negative impacts of media and antifoam selection on a model IgG1 producing CHO cell line.

59 BASIC BIOLOGICAL SCIENCES↗

Value Modeling for Enterprise Resilience

Abstract. The idea that resilience is a tangible, measureable, and desirable system attribute has grown rapidly over the last decade beyond is origins in explaining ecological, physiological, psychological, and social systems. Operational enterprise resilience requires two types of measurement. First, the system must monitor various operational conditions in order to respond to disruptions. These measurements are part of one or more observation, orientation, decision, and action (OODA) loops The OODA control processes that implement a resilience strategy use these measurements to provide robustness, rapid recovery and reconstitution. In order to assess the effectiveness of the resilience strategy, a different class of measurements is necessary. This second type consists of measurements about how well the OODA processes cover critical enterprise functions and the hazards to which the enterprise is exposed. They allow assessment of how well enterprise management processes anticipate, mitigate, and adapt to a changing environment and the degree to which the system is fault tolerant. This paper nominates a theoretical framework, in the form of definitions, a model, and a syntax, that accounts for this important distinction, and in so doing provides a mechanism for bridging resilience management process models and the many proposed cyber-defense metric enumerations.

Henderson, Dale L.↗