Fingerprint Identification Of γ Energy Spectrum Base On Fuzzy Nearness

At present, nuclear disarmament is a international and topical subject. Nuclear disarmament means all nuclear-weapon states must decrease nuclear weapons in number, using agreement or convention to provide for the number of nuclear warhead possessing by all the countries. Now, some nuclear powers in the world are holding a great number of nuclear weapons. Over the past 60 years, only according to the official announcement in the United States, there are more than 4000 nuclear weapons are ready for destruction, and in Russia the number is about 6000.It is imperative for all over the world to reduce the number of nuclear warhead. The main method of nuclear disarmament is reducing nuclear weapons by a big margin through a verifiable and irreversible form. In order to avoid deception between the countries, so we need to distinguish the nuclear warhead through the radiant fingerprint. To avoid the secrets of nuclear weapon out of the sovereign state, theγenergy spectrum of the nuclear warhead is not allowing to see in nuclear disarmament, so the technology ofγenergy spectrum fingerprint played a key role in identified the nuclear warhead that had been reduced.Eachγenergy spectrum corresponds to the unique radioactive nuclide, that is, different radioactive nuclide has different characteristics. We can consider the different characteristics as different fingerprint, so theγenergy spectrum can be defined as"γenergy spectrum Fingerprint".γenergy spectrum consists of full-energy peak, compton plateau, single(double) escape peak, noise background and so on. This paper use HPGe detector onγ-ray fingerprint collection.γ-ray is a radiation form of nucleus energy level jump. It is the nucleus stimulated to produce ray radiation, when the nucleusα-decay andβ-decay.γ-ray can occur three kinds of effects in the detector, that is photoemission, compton effect and pair effect. The full-energy peak is mainly made up of photoemission, but full-energy peak will be likely to be formed from Compton effect and pair effect.Using fuzzy nearness to identifyγenergy spectrum fingerprint is based on fuzzy recognition of fuzzy mathematics, it distinguishes the kinds of nuclear material ,through computing the nearness ofγenergy spectrum fingerprint. First, collecting the fingerprint energy spectrum of the nuclear warhead that is waiting for check, and then, pretreating the fingerprint energy spectrum, at last, using the 3 kinds of change to abstract the characteristics of the fingerprint energy spectrum, and utilizing the nearness to fuzzy recognize theγenergy spectrum fingerprint. In fuzzy mathematics, nearness is an important concept, It is the fuzzy mathematics of fuzzy set of fuzzy relations.Many researchers have propounded lots of nearness formulas. For example, Euclid nearness,Hamming nearness,the Maximum and the Minimum nearness,Arithmetic Mean Minimum nearness, index similarity coefficient nearness and so on. In this paper ,we will adopts ten kinds of nearness formula, through three transform (Fourier transform, cosine transform, wavelet transform) toγenergy spectrum fingerprint to feature extraction,and to different types of energy spectrum for fingerprint fuzzy recognition.In the laboratory,due to various limitations,Theγenergy spectrum of nuclear warheads not easy to get fingerprint collection, we use (152)~Eu,(137)~Cs,and (60)~Co to simulated of nuclear warheads materials, in this paper. With the nearness to statistical fluctuation energy spectrum and different types of energy spectrum, making it possible to make different types of energy spectrum of recognition results,the small the better,Namely nearness the small the better. The statistical fluctuation energy spectrum of recognition results bigger is better. For the statistical fluctuation energy spectrum, nearness are close to 1,is not to recognition out. For different types of energy spectrum, ,nearness the small the better, more close to 0, the identify result is better.