The Development of explosives competencies, training and education in the UK

Competent explosives workers in the Armed Forces and in the civil sector are critical to the safe production, testing and use of explosives. Moreover we need competent explosives specialists to combat the challenge from terrorism and clean up the planet from the explosive hazards that are the legacy of past conflicts. Unfortunately many countries are witnessing a significant loss of capability in this area and are looking at ways of replenishing vital expertise. This paper describes the work done in recent years by the authors and others in the UK to establish numbers of people working in the sector and to consider the skills and knowledge required to carry out their work. It outlines the concept of national occupational standards and the framework of professional and vocational qualifications that are available or are being developed for explosives specialists. It also describes some of the educational and e-learning programmes designed to support this initiative. Ultimately the aim is to address the professionalism of all personnel who deal with explosives in order to reduce the incidence and consequence of accidents and maintain national capability

Pseudo-noise test set for communication system evaluation

A test set for communications systems is described which includes a pseudo noise sequence generator providing a test signal that is fed to a pair of signal channels. The first channel includes a spectrum shaping filter and a conditioning amplifier. The second channel includes a variable delay circuit, a spectrum shaping filter matched to the first filter, and an amplifier. The output of the first channel was applied to the system under test. The output of the system and the output of the second channel are compared to determine the degree of distortion suffered by the test signal due to the communications system

Method of and means for testing a tape record/playback system

A tape record/playback system was tested by first deriving an analog test signal and a band-limited digital reference signal from a pseudo-noise sequence generator driven by a clock signal. It recorded the signals on respective tracks of the system during operation in a record mode. During the playback mode of operation of the system, a delayed analog reference signal without time base variations was reconstructed from the played back reference signal. It was compared with the played back test signal in order to obtain an error signal that was a measure of the performance of the system

Practical Values of Friction Factors

Over the past fifteen years, engineers from Mine Ventilation Services, Inc. (MVS) have measured numerous friction factors at many different types of mining operations. The results of these measurements indicate that standardized friction factors referenced in most ventilation textbooks are greater than those measured in the field for similar airway support systems. Many referenced friction factors are still based on G. E. McElroy\u27s classic paper Engineering Factors in the Ventilation of Metal Mines published in 1935. Most mechanized mines now incorporate airways that are larger, have more advanced support systems, and more uniform openings. This paper describes the measurement techniques and results from friction factor measurements taken during ventilation surveys at various mines with differing support systems. A comparison between textbook and measured values is also presented

Tropical Cyclone Frequency: Turning Paleoclimate Into Projections

Future changes to tropical cyclone (TC) climate have the potential to dramatically impact the social and economic landscape of coastal communities. Paleoclimate modeling and paleohurricane proxy development offer exciting opportunities to understand how TC properties (like frequency) change in response to climate variability on long time scales. However, sampling biases in proxies make it difficult to ascertain whether signals in paleohurricane records are related to climate variability or just stochasticity. Short observations and simulation biases prevent TC models from capturing the full range of climate variability and TC characteristics. Integration of these two data types can help address these uncertainties. Robust data model comparison in paleotempestology will require (a) simulating TCs using new paleoclimate data assimilation products and climate model ensembles, (b) building a central repository of open access paleohurricane proxies, (c) compiling paleohurricane records, and (d) filling key gaps in the existing paleohurricane networks. Incorporating the combined information from both paleohurricane proxies and paleo TC simulations into risk assessments for coastal communities could help improve adaptation strategies