Technology review of flight crucial flight controls

The results of a technology survey in flight crucial flight controls conducted as a data base for planning future research and technology programs are provided. Free world countries were surveyed with primary emphasis on the United States and Western Europe because that is where the most advanced technology resides. The survey includes major contemporary systems on operational aircraft, R&D flight programs, advanced aircraft developments, and major research and technology programs. The survey was not intended to be an in-depth treatment of the technology elements, but rather a study of major trends in systems level technology. The information was collected from open literature, personal communications and a tour of several companies, government organizations and research laboratories in the United States, United Kingdom, France, and the Federal Republic of Germany

The N.A.C.A. Combustion Chamber Gas-sampling Valve and Some Preliminary Test Results

A gas sampling valve of the inertia-operated type was designed for procuring samples of the gases in the combustion chamber of internal combustion engines at identical points in successive cycles so that the analysis of the gas samples thus procured may aid in the study of the process of combustion. The operation of the valve is described. The valve was used to investigate the CO2 content of gases taken from the quiescent combustion chamber of a high speed compression-ignition engine when operating with two different multiple-orifice fuel injection nozzles. An analysis of the gas samples thus obtained shows that the state of quiescence in the combustion chamber is maintained during the combustion of the fuel

Asymmetric Dark Matter and Effective Operators

In order to annihilate in the early Universe to levels well below the measured dark matter density, asymmetric dark matter must possess large couplings to the Standard Model. In this paper, we consider effective operators which allow asymmetric dark matter to annihilate into quarks. In addition to a bound from requiring sufficient annihilation, the energy scale of such operators can be constrained by limits from direct detection and monojet searches at colliders. We show that the allowed parameter space for these operators is highly constrained, leading to non-trivial requirements that any model of asymmetric dark matter must satisfy.Comment: 6 pages, 1 figure. V2 replacement: Citations added. Shading error in Fig. 1 (L_FV panel) corrected. Addition of direct detection bounds on m_chi <5 GeV added, minor alterations in text to reflect these change

Speed is Relative (Human and Animal Running Speeds): Are You a Cheetah, a Chicken, or a Snail?

To put matters in perspective, running speeds for humans and other land animals are compared over various distances. Humans compare quite favorably over longer distances with many species. Both fast and slow human runners can benefit from comparing their individual times in races with other species

Golden Rule Reference: Face-to-Face and Virtual

Reference service in all types of libraries could be improved if librarians actively adopted the mindset of the Golden Rule. The Rule is expressed in some form in many world religions and instructs us to treat others how we would like to be treated. Such an approach has applicability not only in face-to-face reference transactions, but also in virtual reference settings. The empathetic reference librarian should be alert to both verbal and non-verbal clues which can indicate how a patron would like to be treated

HZTool and Rivet: Toolkit and Framework for the Comparison of Simulated Final States and Data at Colliders

A common problem in particle physics is the requirement to reproduce comparisons between data and theory when the theory is a (general purpose) Monte Carlo simulation and the data are measurements of final state observables in high energy collisions. The complexity of the experiments, the obervables and the models all contribute to making this a highly non-trivial task. We describe an existing library of Fortran routines, HZTool, which enables, for each measurement of interest, a comparable prediction to be produced from any given Monte Carlo generator. The HZTool library is being maintained by CEDAR, with subroutines for various measurements contributed by a number of authors within and outside the CEDAR collaboration. We also describe the outline design and current status of a replacement for HZTool, to be called Rivet (Robust Independent Validation of Experiment and Theory). This will use an object-oriented design, implemented in C++, together with standard interfaces (such as HepMC and AIDA) to make the new framework more flexible and extensible than the Fortran HZTool.Comment: Contribution to CHEP06 conferenc

Core Conservation Biology Monographs: A Citation Analysis

Conservation biology is a multidisciplinary subject of recent origins. Analysis of cited monographs from the journal Conservation Biology resulted in a list of 47 monographs which were heavily cited for this discipline. Over half of these were from related disciplines such as ecology, genetics, evolution, population biology, statistics, and natural resource management

Discrete element simulation and nonlinear dynamic analysis of particles in a simple lattice structure

The study of particles interacting in lattice structures allows for insight into the complex interactions of granular flow, and the adaptation of such structures to mechanical apparatuses to handle the separation of bulk particulate matter. Applying methods of computer analysis to the interactions taking place within the particle-lattice system provides a particle level methodology to the study of the phenomenon taking place, as well as a stepping stone for future design of related devices. A two prong approach is presented to the study of such particle-lattice systems. The first approach is composed of adapting an existing discrete element computer code to handle the geometry and peculiars of a particle traveling through a simple triangular lattice system. This discrete element code has been shown in previous research to accurately represent the interactions of such complex systems as a vibrating granular bed, and has been successful in predicting convective transport and other dynamical properties. The second approach, nonlinear dynamic analysis, applies the geometry of the lattice structure and attempts to wrap the physical particle-lattice interaction into a simple mapping function. Finally, a comparative analysis of the two previously mentioned methods of study is performed to physical experiments on an exact replica of the particle-lattice structure at hand