Water Tunnel Tests of the 7.2 Chemical Rocket

This report covers tests of a 2" diameter model of the 7.2" Chemical Rocket to determine its performance and possible means of increasing stability and reducing dispersion. The rocket was tested with the two original tails, the ring tail designated herein as No. 61 and the ring tail with extended fins designated No. 62. Three other tail designs were tested designated No. 63, No. 67, and No. 68. Of these, No. 67 was the only one that produced results superior to the No. 61 and No. 62 designs. This No. 67 Tail has extended fins similar to Tail No. 62 and projects beyond the nozzle about one diameter. Details of these tails are given in Figure 12. Tail No. 62 gave a restoring moment 50% greater than Tail No. 61, and Tail No. 67 gave a restoring moment 45% greater than Tail No. 62, both values being for 5° yaw. It is believed that Tail No. 67 represents about the best that can be done in redesigning the tail, as it produced a fairly high moment, a very large center-of-pressure eccentricity, and only one of the five tails tested has a lower drag coefficient. In this connection it should be noted that all the tails tested gave, without exception, adequate stability to the projectile to insure satisfactory flight after burning is completed. Therefore, the only benefit to be obtained from an increase in the stability above that produced by the original ring tail (No. 61) must come from whatever reduction it might effect in the dispersion occurring during the burning of the propellent. Calculation of the period of oscillation of the projectile in flight, and the equivalent wave length, makes possible a comparison of projectile performance from the standpoint of dynamic stability It can be shown that, for rockets with long burning times, the shorter the wave length for a given projectile, the less will be the dispersion. Using this measure of dispersion, Tail No. 67 would be expected to produce 1S% less dispersion than Tail No. 62, and Tail No. 62, i8% less than Tail No 61. This investigation leads to the conclusion that the No. 61, No. 62, and No. 67 Tails will give a high degree of static stability and it is improbable that much more can be accomplished by a redesign of the tail. It is also a fact that the dynamic stability of the projectile cannot be materially improved if its present physical dimensions are to be retained. The conclusion must, therefore, be reached that the most effective means of lowering the dispersion of this rocket is by reducing the malalignment of the jet with the axis of the projectile and eliminating as far as possible asymmetry in the tail assembly

Water Tunnel Tests of the British "Squid" Projectile Type "C" with Two Alternate Flat Noses

This report covers tests to determine the performance of the "Squid" with three designs of nose, designated No. 42, No 45, and No 46. Practically the only difference in the three noses is in the diameter of the flat face, these diameters being 7.90", 8.93", and 9.95", respectivel

Inferring Quantum Network Topology using Local Measurements

Statistical correlations that can be generated across the nodes in a quantum network depend crucially on its topology. However, this topological information might not be known a priori, or it may need to be verified. In this paper, we propose an efficient protocol for distinguishing and inferring the topology of a quantum network. We leverage entropic quantities -- namely, the von Neumann entropy and the measured mutual information -- as well as measurement covariance to uniquely characterize the topology. We show that the entropic quantities are sufficient to distinguish two networks that prepare GHZ states. Moreover, if qubit measurements are available, both entropic quantities and covariance can be used to infer the network topology. We show that the protocol can be entirely robust to noise and can be implemented via quantum variational optimization. Numerical experiments on both classical simulators and quantum hardware show that covariance is generally more reliable for accurately and efficiently inferring the topology, whereas entropy-based methods are often better at identifying the absence of entanglement in the low-shot regime

Statistical Mechanics of Glass Formation in Molecular Liquids with OTP as an Example

We extend our statistical mechanical theory of the glass transition from examples consisting of point particles to molecular liquids with internal degrees of freedom. As before, the fundamental assertion is that super-cooled liquids are ergodic, although becoming very viscous at lower temperatures, and are therefore describable in principle by statistical mechanics. The theory is based on analyzing the local neighborhoods of each molecule, and a statistical mechanical weight is assigned to every possible local organization. This results in an approximate theory that is in very good agreement with simulations regarding both thermodynamical and dynamical properties

Considering Intra-individual Genetic Heterogeneity to Understand Biodiversity

In this chapter, I am concerned with the concept of Intra-individual Genetic Hetereogeneity (IGH) and its potential influence on biodiversity estimates. Definitions of biological individuality are often indirectly dependent on genetic sampling -and vice versa. Genetic sampling typically focuses on a particular locus or set of loci, found in the the mitochondrial, chloroplast or nuclear genome. If ecological function or evolutionary individuality can be defined on the level of multiple divergent genomes, as I shall argue is the case in IGH, our current genetic sampling strategies and analytic approaches may miss out on relevant biodiversity. Now that more and more examples of IGH are available, it is becoming possible to investigate the positive and negative effects of IGH on the functioning and evolution of multicellular individuals more systematically. I consider some examples and argue that studying diversity through the lens of IGH facilitates thinking not in terms of units, but in terms of interactions between biological entities. This, in turn, enables a fresh take on the ecological and evolutionary significance of biological diversity

Quantum-statistical transport phenomena in memristive computing architectures

The advent of reliable, nanoscale memristive components is promising for next generation compute-in-memory paradigms, however, the intrinsic variability in these devices has prevented widespread adoption. Here we show coherent electron wave functions play a pivotal role in the nanoscale transport properties of these emerging, non-volatile memories. By characterizing both filamentary and non-filamentary memristive devices as disordered Anderson systems, the switching characteristics and intrinsic variability arise directly from the universality of electron transport in disordered media. Our framework suggests localization phenomena in nanoscale, solid-state memristive systems are directly linked to circuit level performance. We discuss how quantum conductance fluctuations in the active layer set a lower bound on device variability. This finding implies there is a fundamental quantum limit on the reliability of memristive devices, and electron coherence will play a decisive role in surpassing or maintaining Moore's Law with these systems.Comment: 13 pages, 6 figure

Dr. Zompo: an online data repository for Zostera marina and Posidonia oceanica ESTs

As ecosystem engineers, seagrasses are angiosperms of paramount ecological importance in shallow shoreline habitats around the globe. Furthermore, the ancestors of independent seagrass lineages have secondarily returned into the sea in separate, independent evolutionary events. Thus, understanding the molecular adaptation of this clade not only makes significant contributions to the field of ecology, but also to principles of parallel evolution as well. With the use of Dr. Zompo, the first interactive seagrass sequence database presented here, new insights into the molecular adaptation of marine environments can be inferred. The database is based on a total of 14 597 ESTs obtained from two seagrass species, Zostera marina and Posidonia oceanica, which have been processed, assembled and comprehensively annotated. Dr. Zompo provides experimentalists with a broad foundation to build experiments and consider challenges associated with the investigation of this class of non-domesticated monocotyledon systems. Our database, based on the Ruby on Rails framework, is rich in features including the retrieval of experimentally determined heat-responsive transcripts, mining for molecular markers (SSRs and SNPs), and weighted key word searches that allow access to annotation gathered on several levels including Pfam domains, GeneOntology and KEGG pathways. Well established plant genome sites such as The Arabidopsis Information Resource (TAIR) and the Rice Genome Annotation Project are interfaced by Dr. Zompo. With this project, we have initialized a valuable resource for plant biologists in general and the seagrass community in particular. The database is expected to grow together with more data to come in the near future, particularly with the recent initiation of the Zostera genome sequencing project

Структура вірусних діарей у дітей на Сумщині

Гострі кишкові інфекції (ГКІ) стійко посідають одне з провідних місць серед усіх інфекційних захворювань, характеризуються широкою поширеністю, високою частотою розвитку тяжких форм і ускладнень. Прогрес у галузі лабораторних методів діагностики дозволив істотно розширити уявлення про етіологічні чинники хвороби: у країнах, що розвиваються, домінують діарейні інфекції бактерійної етіології, а в економічно розвинених країнах - вірусної. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/3228