Team cognition in a cyber defense context: focus on social support behaviors

In the face of increasingly prominent cyber security issues, the organization of cyber team analysts has become crucial to thwart cyber threats. Few studies have examined the functioning of the team and the interaction between individuals in a cyber defense context and how the context influences team adaptation. The present study investigates team cognition in a cyber defense context and in particular the nature of task- or team-centered communication among analysts during a cyber defense simulation exercise. Results indicate that markers of situation assessment and shared mental models are both strategically present and linked. Nevertheless, the frequency of these markers varies depending on the quantity and quality of problems encountered; in particular, variations in social support behaviors are observed. Decreasing social support behaviors during high level activities suggests the adaptation of social behaviors depending on the threats and attacks on the system. Theoretical and practical implications are discussed in terms of theories and potential consequences for strategic adaptation and team resilience.

     

Gallium distribution and electrical activation in Ga+-implanted Si

Gallium distribution profiles in Ga⁺-implanted silicon have been measured by secondary ion mass spectrometry (SIMS) and differential Hall effect methods. The previously reported penetrating tails are not observed for as-implanted samples. The redistribution of Ga during annealing is affected by ion damage and effects due to recrystallization of the amorphous layer. Electrical carrier profiles indicate that carrier concentration higher than the usual Ga solid solubility can be achieved in Ga-implanted Si recrystallized at 600‡C. However, this large acceptor concentration diminishes after higher temperature annealing. For 900‡C anneals, the carrier concentration is limited by the Ga solid solubility and some compensation due to unannealed ion damage. Work Supported by the Joint Service Electronics Program (U.S. Army, U.S. Navy, U.S. Air Force) under Contracts DAAB-07-72-C-0259 and DAAG-16-78-C-0016, and by the National Science Foundation under Grants DMR-77-22228, DMR-76-01058, and CHE-76-03694.     

Electrodeposited Cu2ZnSnSe4 thin film solar cell with 7% power conversion efficiency

High performance Cu₂ZnSnSe₄ (CZTSe) photovoltaic materials were synthesized by electrodeposition of metal stack precursors followed by selenization. A champion solar cell with 7.0% efficiency is demonstrated. This is the highest efficiency among all of the CZTSe solar cells prepared from electrodeposited metallic precursors reported to‐date. Device parameters are discussed from the perspective of material microstructure and composition in order to improve performance. In addition, a high performance electrodeposited CZTS (S only) solar cell was demonstrated and its device characteristics were compared against the CZTSe (Se only) cell. Using secondary ion mass spectrometry for the analysis of the chemical composition of the absorber layer, a higher concentration of oxygen in the electrodeposited absorber is thought to be the root cause of the lower performance of the electrodeposited CZTS or CZTSe solar cells with respect to a solar cell fabricated by evaporation. The grain boundary areas of Sn‐rich composition are thought to be responsible for the lower shunt resistance commonly observed in CZTSe devices. We measured the longest minority carrier lifetime of 18 ns among all reported kesterite devices. This work builds a good baseline for obtaining higher efficiency earth‐abundant solar cells, while it highlights electrodepositon as a low cost and feasible method for earth‐abundant thin film solar cell fabrication. Copyright © 2013 John Wiley & Sons, Ltd.     

High accuracy plasma density measurement using hybrid Langmuir probe and microwave interferometer method

High spatial resolution plasma density measurements have been taken as part of an investigation into magnetic nozzle physics at the NASA/MSFC Propulsion Research Center. These measurements utilized a Langmuir triple probe scanned across the measurement chord of either of two stationary rf interferometers. By normalizing the scanned profile to the microwave interferometer line-integrated density measurement for each electrostatic probe measurement, the effect of shot-to-shot variation of the line-integrated density can be removed. In addition, by summing the voltage readings at each radial position in a transverse scan, the line density can be reconstituted, allowing the absolute density to be determined, assuming that the shape of the profile is constant from shot to shot. The spatial and temporal resolutions of this measurement technique depend on the resolutions of the scanned electrostatic probe and the interferometer. The measurement accuracy is 9%-15%, which is on the order of the accuracy of the rf interferometer. The measurement technique was compared directly with both scanning rf interferometer and standard Langmuir probe theory. The hybrid technique compares favorably with the scanning rf interferometer, and appears more accurate than probe theory alone. Additionally, our measurement technique is generally applicable even for nonaxisymmetric plasmas.     

Protection by acetylsalicylic acid and other agents in experimental acute interstitial pneumonia of calves

In experimental acute interstitial pneumonia caused by Ascaris suum, therapy with aspirin (acetylsalicylic acid) provided symptomatic control of the condition, reducing or abolishing the characteristic "setback". Treatment with antihistamines or antiserotonin agents caused no observable clinical improvements.     

Degradation of individual cells in a module measured with differential IV analysis

A methodology is developed for the extraction of cell‐level properties from the analysis of differential IV response in a solar module with series connected cells. Through a combination of simulation and experimental verification we show that the shunt resistance and short circuit current of individual cells can be determined from a peak in the module differential resistance with cells that are partially shaded. The magnitude of the peak is equal to the shunt resistance of the cell for small values of shunt resistance. The current at which the peak occurs is proportional to the product of the short circuit current and the shading factor of the particular cell. With this methodology, we are able to measure degradation of 72 individual cells in a single commercial module after a high temperature/high humidity/high voltage stress test. Therefore, the statistics of degradation in this test were improved 72‐fold. Copyright © 2010 John Wiley & Sons, Ltd.     

A correlation of atomic and electrical measurements of Cr and residual donors in thermally processed semi-insulating GaAs

Chronium redistribution resulting in residual donor decompensation has been proposed to explain near-surface type-conversion in furnace-annealed, semi-insulating GaAs. We report here correlations of Cr depth profiles and residual donor atom densities determined by SIMS with Hall effect and C-V electrical measurements of carrier densities which substantiate the above hypothesis. Furthermore, a 1:1 Cr-to-donor compensation ratio iis observed for Cr doping levels of ~ 10¹⁷ cm^?3.     

Post Porosity Plasma Protection: Scaling of Efficiency with Porosity

Increasing the porosity of oxycarbosilane dielectrics is a key approach to lower the interconnect signal delay and thus enable manufacturing of lower power consumption and higher performance microprocessors. However, this path leads to excessive dielectric process damage as the industry adapts procedures developed for dense and microporous insulators to mesoporous materials. Currently ultralow dielectric constant (k) materials cannot be integrated at the most aggressive pitch. Here, it is reported that the post porosity plasma protection enables the mitigation of process damage across a wide range of porosity regimes. The exponential increase in plasma damage with porosity when going from microporous k = 2.4 to mesoporous k = 1.8 is shown. Using the same range of materials, the strategy allows a reduction in process damage to a constant minimal level on both blanket wafers and patterned structures. The results demonstrate how the strategy can enable the extendibility of current materials and processes to future technology nodes.     

Pediatric headaches: what do the children want?

Sumatriptan, a selective 5-hydroxytryptamine (5HT1D)-receptor agonist, has recently been introduced in the pharmacotherapy of acute migrane attacks. The potential vasoactive effect of sumatriptan on human dural vessels in vivo, however, is still a matter of controversy. We investigated the effects of sumatriptan on dural vessels after subcutaneous or intra-arterial injection. During interventional angiography, the middle meningeal artery (MMA) of nine patients was catheterized with a microcatheter using the transfemoral route. Three MMA were entirely normal, two supplied a dural arteriovenous fistula (AVF) and four were transdural feeders to a brain arteriovenous malformation (AVM). Sumatriptan was injected either into the subcutaneous tissue of the right shoulder (6 mg, two patients) or into the catheterized MMA (2 mg, six patients). The substance caused a marked vasoconstriction of the three normal MMA, visible angiographically and confirmed by intravascular Doppler ultrasonography. Vasoconstriction was still present in the last angiogram obtained 15 min post-injection. Slightly hypertrophied feeders to dural AVF and to brain AVM showed some vasoconstriction in one and four patients, respectively. In two patients with markedly hypertrophied dural feeders to a dural AVF and to a brain AVM, respectively, rapid shunting probably prevented obvious vasoactive effects of sumatriptan. The data obtained by angiography and intravascular Doppler ultrasonography provide strong evidence that sumatriptan has a vasoconstrictive effect on normal as well as hypertrophied dural vessels.