Decision support for network connectivity planning

The aim of this thesis is to design and implement a highly graphical, computer-based decision support system (DSS) to assist in the design of 'optimum' network connectivity plans. The Web Spinner DSS is a 'proof-of- concept' system which highlights how the marriage of basic decision methodologies with a modern computing environment can be used to create a robust decision support tool. The basic concepts of decision support systems and their practical value to today's information worker are discussed. The challenge in designing the best network plan is presented along with several examples illustrating the complexities and scale of the problem. The Web Spinner DSS is presented as a potential solution to at least part of the network design problem. The capabilities and design principles of the Web Spinner are provided along with a tutorial and a sample problem. Finally, some suggestions for improving the Web Spinner DSS are reviewed. It is shown that some of these improvements can greatly enhance the value of the Web Spinner in supporting decisions related to network connectivity.http://archive.org/details/decisionsupportf1094532265NAU.S. Navy (U.S.N.) authorApproved for public release; distribution is unlimited

Interplay between shape and composition in bimetallic nanoparticles revealed by an efficient optimal-exchange optimization algorithm

Despite the large relevance of bimetallic metal nanoparticles for heterogeneous catalysis, the relation between their shape and elemental composition remains elusive. Here, we investigate this relationship by implementing and applying global optimization methods enhanced with a novel optimal-exchange algorithm. In particular, we determine the lowest energy chemical orderings for PtAu nanoparticles, revealing that the most stable shape changes from highly symmetric structures for pure particles to distorted and less symmetric shapes for intermediate compositions. The presented method leverages the local atomic contributions to an empirical surrogate energy expression to identify optimal atom exchanges. This also allows us to pinpoint the origin of the stability of distorted shapes, revealing a favorable energy trade-off when over-coordinating Pt and under-coordinating Au upon distorting the particle shape

Investigating the effect of proactive interference control training on intrusive memories = Investigando el efecto del entrenamiento de control de interferencias proactivas en las memorias intrusivas = 研究主动干扰控制训练对闯入性记忆的影响

Intrusive re-experiencing is a hallmark symptom of Posttraumatic Stress Disorder (PTSD). According to prominent models of intrusive phenomena, intrusive memories may result from impairments in the efficiency of working memory capacity (WMC), more specifically proactive interference control. Yet, experimental research is scarce. Therefore, the present study aimed to investigate experimentally the role of proactive interference control in intrusive memories. We randomly assigned 57 healthy participants to either receive a high interference control training or a low interference control training. Participants were then exposed to highly distressing film clips. WMC was assessed before and after the training. Intrusion symptoms were assessed directly post-training and after one week using an Intrusion Provocation Task (IPT), a one-week intrusions diary, and the retrospective intrusion subscale of the Impact of Event Sale – Revised (IES-R). Results indicated that both groups reported improvements in WMC and fewer intrusions on the second IPT post-training, with no differences between groups. Similarly, no group differences on intrusions were found at one-week follow-up (i.e., intrusion diary and IES-R). To conclude, these data are not consistent with the hypothesis that WMC plays a role in intrusive re-experiencing. Implications for future research are discussed. / La re-experiencia intrusiva es un síntoma distintivo del trastorno por estrés postraumático (TEPT). De acuerdo con los prominentes modelos de fenómenos intrusivos, las memorias intrusivas pueden resultar en deterioros en la eficiencia de la capacidad de memoria de trabajo (CMT), más específicamente del control proactivo de interferencias. Sin embargo, la investigación experimental a este respecto es escasa. Por lo tanto, el presente estudio tuvo como objetivo investigar experimentalmente el papel del control proactivo de interferencias en las memorias intrusivas. Asignamos aleatoriamente 57 participantes sanos a recibir, ya sea, un entrenamiento de control de alta interferencia o un entrenamiento de control de baja interferencia. Luego, los participantes fueron expuestos a videoclips de películas altamente angustiantes. La CMT fue evaluada antes y después del entrenamiento. Los síntomas de intrusión se evaluaron directamente después del entrenamiento y después de una semana utilizando una Tarea de Provocación de Intrusión (IPT), registro diario de intrusiones (por una semana), y la subescala de intrusión retrospectiva de la Escala del Impacto del Evento - Revisada (IES-R). Los resultados indicaron que ambos grupos experimentaron mejoras en la CMT y reducción de intrusiones en la segunda IPT posterior al entrenamiento, sin diferencias entre los grupos. De manera similar, no se encontraron diferencias de grupo en las intrusiones en el seguimiento de una semana (es decir, en el diario de intrusiones y la IES-R). Para concluir, estos datos no son consistentes con la hipótesis de que la CMT desempeña un papel en la re-experiencia intrusiva. Se discuten las implicaciones para futuras investigaciones. / 闯入性再体验是创伤后应激障碍（PTSD）的标志性症状。根据闯入现象的经典模型，闯入性记忆可能是由工作记忆容量（WMC）效率的损害引起的，更具体地说是主动干扰控制。然而，这方面实验研究很少。因此，本研究通过实验研究主动干扰控制在闯入性记忆中的作用。我们随机分配了57名健康被试，以接受高干扰控制训练或低干扰控制训练。然后被试接触到令人非常痛苦的电影片段。在训练前后对WMC进行了评估。在训练后和一周后随访使用闯入激发任务（IPT），一周闯入症状日记以及事件影响量表修订版（IES－R）的回顾性闯入子量表直接评估闯入症状。结果表明，两组均报告WMC改善，第二次IPT训练后闯入较少，两组间无差异。同样，在一周的随访中没有发现闯入的群体差异（即闯入日记和IES-R）。总之，这些数据与WMC在闯入性再体验中发挥作用的假设不一致。文中讨论了对未来研究的启示

Magnetic Dipole Sum Rules for Odd-Mass Nuclei

Sum rules for the total- and scissors-mode M1 strength in odd-A nuclei are derived within the single-j interacting boson-fermion model. We discuss the physical content and geometric interpretation of these sum rules and apply them to ^{167}Er and ^{161}Dy. We find consistency with the former measurements but not with the latter.Comment: 13 pages, Revtex, 1 figure, Phys. Rev. Lett. in pres

Human perceptual learning is delayed by the N-methyl-D-aspartate receptor partial agonist D-cycloserine

Background: The optimisation of learning has long been a focus of scientific research, particularly in relation to improving psychological treatment and recovery of brain function. Previously, partial N-methyl-D-aspartate agonists have been shown to augment reward learning, procedural learning and psychological therapy, but many studies also report no impact of these compounds on the same processes. Aims: Here we investigate whether administration of an N-methyl-D-aspartate partial agonist (D-cycloserine) modulates a previously unexplored process – tactile perceptual learning. Further, we use a longitudinal design to investigate whether N-methyl-D-aspartate-related learning effects vary with time, thereby providing a potentially simple explanation for apparent mixed effects in previous research. Methods: Thirty-four volunteers were randomised to receive one dose of 250 mg D-cycloserine or placebo 2 h before tactile sensitivity training. Tactile perception was measured using psychophysical methods before and after training, and 24/48 h later. Results: The placebo group showed immediate within-day tactile perception gains, but no further improvements between-days. In contrast, tactile perception remained at baseline on day one in the D-cycloserine group (no within-day learning), but showed significant overnight gains on day two. Both groups were equivalent in tactile perception by the final testing – indicating N-methyl-D-aspartate effects changed the timing, but not the overall amount of tactile learning. Conclusions: In sum, we provide first evidence for modulation of perceptual learning by administration of a partial N-methyl-D-aspartate agonist. Resolving how the effects of such compounds become apparent over time will assist the optimisation of testing schedules, and may help resolve discrepancies across the learning and cognition domains

Why Attackers Lose: Design and Security Analysis of Arbitrarily Large XOR Arbiter PUFs

In a novel analysis, we formally prove that arbitrarily many Arbiter PUFs can be combined into a stable XOR Arbiter PUF. To the best of our knowledge, this design cannot be modeled by any known oracle access attack in polynomial time. Using majority vote of arbiter chain responses, our analysis shows that with a polynomial number of votes, the XOR Arbiter PUF stability of almost all challenges can be boosted exponentially close to 1; that is, the stability gain through majority voting can exceed the stability loss introduced by large XORs for a feasible number of votes. Considering state-of-the-art modeling attacks by Becker and Rührmair et al., our proposal enables the designer to increase the attacker\u27s effort exponentially while still maintaining polynomial design effort. This is the first result that relates PUF design to this traditional cryptographic design principle

Nuclear Scissors Mode with Pairing

The coupled dynamics of the scissors mode and the isovector giant quadrupole resonance are studied using a generalized Wigner function moments method taking into account pair correlations. Equations of motion for angular momentum, quadrupole moment and other relevant collective variables are derived on the basis of the time dependent Hartree-Fock-Bogoliubov equations. Analytical expressions for energy centroids and transitions probabilities are found for the harmonic oscillator model with the quadrupole-quadrupole residual interaction and monopole pairing force. Deformation dependences of energies and $B(M1)$ values are correctly reproduced. The inclusion of pair correlations leads to a drastic improvement in the description of qualitative and quantitative characteristics of the scissors mode.Comment: 36 pages, 5 figures, the results of calculation by another method and the section concerning currents are adde

Effect of maternal panic disorder on mother-child interaction and relation to child anxiety and child self-efficacy

To determine whether mothers with panic disorder with or without agoraphobia interacted differently with their children than normal control mothers, 86 mothers and their adolescents (aged between 13 and 23 years) were observed during a structured play situation. Maternal as well as adolescent anxiety status was assessed according to a structured diagnostic interview. Results showed that mothers with panic disorder/agoraphobia showed more verbal control, were more criticizing and less sensitive during mother-child interaction than mothers without current mental disorders. Moreover, more conflicts were observed between mother and child dyadic interactions when the mother suffered from panic disorder. The comparison of parenting behaviors among anxious and non-anxious children did not reveal any significant differences. These findings support an association between parental over-control and rejection and maternal but not child anxiety and suggest that particularly mother anxiety status is an important determinant of parenting behavior. Finally, an association was found between children’s perceived self-efficacy, parental control and child anxiety symptoms