A Systems Engineering Approach to Aircraft Kinetic Kill Countermeasures Technology: Development of an Active Aircraft Defense System for the C/KC-135 Aircraft

Modern Surface to Air Missiles (SAMs) present a significant threat to today\u27s military and civilian aircraft. Current countermeasure systems such as flares and chaff rely on decoying the missile threat and do not provide adequate protection against advanced computerized missiles (Schaffer, 1993:1). An aircraft defense system that actively seeks out and defeats an incoming missile by placing a physical barrier in the missile\u27s path offers a promising alternative to current countermeasures technology. This thesis reports the preliminary design of an active aircraft defense system for the protection of the C/KC-135 aircraft from SAMs. The developed system utilizes a kinetic kill mechanism to protect the aircraft from shoulder launched missiles while the aircraft is in the takeoff and climb-out configurations. Both smart anti-missile expendables and dumb projectile expendables are evaluated. The iterative Systems Engineering approach is used to narrow the solution set to the optimal design. The final outcome is the refined design of two candidate aircraft defense system employing a kinetic kill mechanism. Both systems utilize a modified ultra-violet tracker and employ one of two types of nets, one made out of Detonation Cord and the other made out of Spectra

Beyond Environmental Regulatory Fragmentation: Signs of Integration in the Case of the Great Lakes Basin

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72007/1/j.1468-0491.1995.tb00197.x.pd

The ABC130 barrel module prototyping programme for the ATLAS strip tracker

For the Phase-II Upgrade of the ATLAS Detector, its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100 % silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-25) and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.Comment: 82 pages, 66 figure

Observations of short-range, high-LET recoil tracks in CR-39 plastic nuclear track detector by visible light microscopy

Using standard visible light microscopy, we are able to observe particle tracks produced by <10 micro meter range target fragment recoils in CR-39 plastic nuclear track detector (PNTD) following short chemical etching (bulk etch B < 1 micro meter). In accelerator irradiations, targets of varying composition, including a number of elemental targets of high Z, were exposed in contact with layers of CR-39 PNTD to beams of 60 MeV, 230 MeV, and 1 GeV protons at doses of 10 - 50 Gy. Chemical etching of CR-39 under standard conditions (50 degreeC, 6.25 N NaOH) for 2 - 4 h (removed layer B = 0.5 - 1.0 mm) yielded secondary track densities of 10^5 - 10^6 cm2 observable under a standard optical microscope with 500x - 800x magnification.Ordinarily such a short duration etch would not be expected to enlarge the tracks sufficiently for them to be resolved by visible light optics. However, due to the short-range of the particles, a longer chemical processing would have over-etched the tracks until they were no longer recognizable. The tracks we observe in CR-39 PNTD irradiated in these experiments are the result of residual heavy recoil fragments returning to equilibrium via evaporation processes following proton-induced knock outof light particles via preequilibrium processes. Because the heavy recoil particles are very near the end of their ranges (i.e. in the Bragg peak), their LET is extremely high and changes rapidly. Consequently, the tracks they produce in CR-39 PNTD often take the form of long tubes rather than the conical etch pits produced by higher energy particles

Object and File Management in the EXODUS Extensible Database System

This paper describes the design of the object-oriented storage component of EXODUS, an extensible database manaaement~svstern currently under development at the University of-Wiscon&amp;t. The basic abstraction in the EXODU’S storage system is the storage object, an uninterpmted variable-length m&amp;z &amp; of arbitrary size; higher level abstractions such as records and indices am supported via the storage object abstraction. One of the key design %atums described here is a scheme,for managing large dynamic objects, as storage objects can occupy many disk pages and can grow or s.hrink at arbitrary points. The data structure and algorithmsused to su-port such objects are described, and nerformance results from a ore s-iminary prototype of the EXODUS. large-object management scheme am presented. A scheme for maintainin versions of large objects is also described. We then describe the fi K e structure used in the EXODUS storage system, which provides a mechanism for grouping and sequencing through a set of related storage objects. In addition to object and file management. we discuss the EXODUS approach to buffer management, &amp;ntcurrency control, and recovery, both for small and large objects. 1

Assessment of radiation shielding materials for protection of space crews using CR-39 plastic nuclear track detector

A significant obstacle to long duration human space exploration such as the establishment of a permanent base on the surface of the Moon or a human mission to Mars is the risk posed by prolonged exposure to space radiation. In order to keep mission costs at acceptable levels while simultaneously minimizing the risk from diation to space crew health and safety, a judicious use of optimized shielding materials will be required.We have undertaken a comprehensive study using CR-39 plastic nuclear track detector (PNTD) to characterize the radiation shielding properties of a range of materialsdboth common baseline materials such as Al and polyethylene, and novel multifunctional materials such as carbon compositesdat heavy ion accelerators. The study consists of analyzing CR-39 PNTD exposed in front of and behind shielding targets of varying composition and at a number of depths (target thicknesses) relevant to the development and testing of materials for space radiation shielding. Most targets consist of 10 cm* 10 cm slabs of solid materials ranging in thickness from 1 to >30 g/cm2. Exposures have been made to beams of C, O, Ne, Si, Ar, and Fe at energies ranging from 290 MeV/amu to 1 GeV/amu at the National Institute of Radiological Sciences HIMAC and the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory. Analysis of the exposed detectors yields LET spectrum, dose, and dose equivalent as functions of target depth and composition, and incident heavy ion charge, energy, and fluence. Efforts are currently underway to properly weigh and combine these results into a single quantitative estimate of a material\u27s ability to shield space crews from the interplanetary galactic cosmic ray flux

epiforecasts/EpiSoon

Forecasting the effective reproduction number over short timescales