In this paper, two suboptimum detectors are proposed for coherent radar signal detection in K-distributed clutter. Assuming certain values for several initial moments of clutter amplitude, the characteristic function of the clutter amplitude is approximated by a limited series. Using the Pade approximation, it is then converted to a rational fraction. Thus, the pdf of the clutter amplitude is o...

We consider the use of single-photon counting detectors in coherence-domain imaging. Detectors operated in this mode exhibit reduced noise, which leads to increased sensitivity for weak light sources and weakly reflecting samples. In particular, we experimentally demonstrate the possibility of using superconducting single-photon detectors (SSPDs) for optical coherence-domain reflectometry (OCDR...

The use of modeling programs such as MCNP to predict the response of HPGe detectors is increasing in importance. Accurate simulation of germanium detectors to incident gamma rays relies on knowledge of the performance of the detector in different detector-source geometries. Two important performance parameters are the resolution and sensitivity. The resolution is the FWHM and FW.1M/FWHM ratio. ...

In this paper we present a new system for doubletalk detection that uses multiple signal detectors/discriminators based on recurrent networks. The goal is to build a simple system that learns to combine information from different signal sources to make robust decisions even under changing noise conditions. In this paper we use three detectors two of these are frequency domain signal detectors, ...

In terahertz (THz) materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8...

Ultra low noise bolometers are required for space based astronomical observations. Extremely sensitive detectors are necessary for a deep full-sky survey of distant extragalactic sources in the submillimeter-wave region corresponding to the extraterrestrial background spectrum minimum. A deep full-sky survey is the main goal of the Submillimetron project of the cryogenically cooled telescope on...

background: more than 50% of the total dose received by human beings from all sources of radiation (both from natural and manmade) comes from radon and its progeny which is responsible for lung cancer in many cases. materials and methods: in the present study, the measurements have been carried out by using twin chamber dosimeter cups with lr-115 type-ii detectors. the value of track density of...

introduction natural and man made radioactive sources exist in our environment they can enter into our food chains. one of these is the soil-mushroom-human chain. high level doses of natural radiation can cause hazards to humans. materials and methods samples of agaricus bisporus cultivated edible mushroom in tehran province- iran were collected from 7 farms. specific activity of 226ra, 228ra, ...

background: radon, thoron and their progenies are the most important contributions to human exposure from natural sources. radon exists in soil gas, building materials, indoor atmosphere etc. among all the natural sources of radiation dose to human beings, inhalation of radon contributes a lot. the work presented here emphasizes the long term measurements of radon, thoron and their progeny conc...