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Over the past decade, considerable work has been performed on the application of digitizers to measurement in high voltage (HV) impulse tests and many laboratories are now using digitizers to record HV tests. The present standards on HV measurements make no explicit provision for the use of digital recorders, giving urgency to the need to provide the necessary characteristics, calibrations and tests required to qualify a digitizer for recording HV tests. This paper shows how the main tests described in the proposed standard can be applied towards qualifying an impulse digitizer for HV impulse measurements. Experimental results from the application of these techniques to different digitizers are presented. Previous low frequency measurements have indicated that high frequencies can be a problem and this paper reports some measurements at high frequencies. The consequences of these measurements for electromagentic compatibility are discussed.

Peer inside the mind of violent child molester Nathanael Bar-Jonah. Personal coded writings, life-long behaviors and victim testimony reveal how he operated and the difficulties law enforcement experienced stopping him. This narrative follows Bar-Jonah's evolution from religious beginnings to hunting children. Extensively researched medical and psychological details explain what is known about child predators and shows how to recognize pedophile behavior and protect children. ABOUT THE AUTHOR A medical school honors graduate and Internal Medicine specialist, Dr. Kuffel has extensive experience in trauma and emergency medicine. This work brought her close to many crime victims, investigators and perpetrators. Unique cooperation from Montana law enforcement, Bar-Jonah and his victims greatly assisted her search for accuracy in writing this educational true crime story.

Of the 36 composite insulators field-tested at Brighton, Britain, 19 were sent to IREQ for laboratory evaluation. The initial test program included insulator inspection, surface evaluation of weathershed material, mechanical proof tests, electrical tests consisting of clean and salt fog tests, and material tests including hardness, chemical composition, and tracking wheel. The initial program was later enlarged to include a similar evaluation on six 25 kV composite insulators field-tested in a coastal environment by Nova Scotia Power Corp. This paper describes the results of the two testings.

Report on the measurements of the dynamic performance of 8 diferent digitizers, with an analysis to show the types and magnitudes of error to which each digitizer is prone. The impact of these errors on the measurements of fast single-shot transients, such as front chopped impulses with times-to-chopping in the range of 500 ns (the fastest covered by the standards) to a few ns, is examined and the suitable range of application of each digitizer is presented.