Cryptography based on neural networks - analytical results

Mutual learning process between two parity feed-forward networks with discrete and continuous weights is studied analytically, and we find that the number of steps required to achieve full synchronization between the two networks in the case of discrete weights is finite. The synchronization process is shown to be non-self-averaging and the analytical solution is based on random auxiliary variables. The learning time of an attacker that is trying to imitate one of the networks is examined analytically and is found to be much longer than the synchronization time. Analytical results are found to be in agreement with simulations

Research and applications: Artificial intelligence

The program is reported for developing techniques in artificial intelligence and their application to the control of mobile automatons for carrying out tasks autonomously. Visual scene analysis, short-term problem solving, and long-term problem solving are discussed along with the PDP-15 simulator, LISP-FORTRAN-MACRO interface, resolution strategies, and cost effectiveness

Trends in aerosol abundances and distributions

The properties of aerosols that reside in the upper atmosphere are described. Special emphasis is given to the influence these aerosols have on ozone observation systems, mainly through radiative effects, and on ambient ozone concentrations, mainly through chemical effects. It has long been appreciated that stratospheric particles can interfere with the remote sensing of ozone distribution. The mechanism and magnitude of this interference are evaluated. Separate sections deal with the optical properties of upper atmospheric aerosols, long-term trends in stratospheric aerosols, perturbations of the stratospheric aerosol layer by volcanic eruptions, and estimates of the impacts that such particles have on remotely measured ozone concentrations. Another section is devoted to a discussion of the polar stratospheric clouds (PSC's). These unique clouds, recently discovered by satellite observation, are now thought to be intimately connected with the Antarctic ozone hole. Accordingly, interest in PSC's has grown considerably in recent years. This chapter describes what we know about the morphology, physical chemistry, and microphysics of PSC's

Training a perceptron in a discrete weight space

On-line and batch learning of a perceptron in a discrete weight space, where each weight can take $2 L+1$ different values, are examined analytically and numerically. The learning algorithm is based on the training of the continuous perceptron and prediction following the clipped weights. The learning is described by a new set of order parameters, composed of the overlaps between the teacher and the continuous/clipped students. Different scenarios are examined among them on-line learning with discrete/continuous transfer functions and off-line Hebb learning. The generalization error of the clipped weights decays asymptotically as $exp(-K \alpha^2)$/$exp(-e^{|\lambda| \alpha})$ in the case of on-line learning with binary/continuous activation functions, respectively, where $\alpha$ is the number of examples divided by N, the size of the input vector and $K$ is a positive constant that decays linearly with 1/L. For finite $N$ and $L$, a perfect agreement between the discrete student and the teacher is obtained for $\alpha \propto \sqrt{L \ln(NL)}$. A crossover to the generalization error $\propto 1/\alpha$, characterized continuous weights with binary output, is obtained for synaptic depth $L > O(\sqrt{N})$.Comment: 10 pages, 5 figs., submitted to PR

The minimally-invasive thyroidectomy incision: a histological analysis.

BACKGROUND: Minimally invasive thyroidectomy (MIT) has gained popularity in the surgical management of benign and malignant pathology of the thyroid. One of the main benefits of utilizing this technique is the use of smaller incisions resulting in increased cosmetic satisfaction. Unfortunately, the retraction required for adequate exposure during MIT may lead to skin damage, impaired wound healing and poor cosmetic outcomes. Some have proposed that excising incision edges prior to closure may improve cosmesis. A review of the literature does not reveal any histologic evidence to support this technique. MATERIAL/METHODS: In this prospective observational study, nine subjects undergoing MIT were identified. Both the superior and inferior skin edges were excised and labeled for orientation. Specimens were sent for hematoxylin and eosin staining and histologic analysis by a staff pathologist. RESULTS: All specimens showed no significant findings such as damage to the architecture of the dermis, acute inflammation, edema or evidence of hemorrhage. Focal blood vessel ectasia within the dermis was identified in three of nine subjects. CONCLUSIONS: Our findings do not yield a histological basis supporting the routine trimming of incisions during MIT. Although no significant findings were noted histologically, further studies are warranted to investigate the long-term cosmetic outcome of MIT incisions

Retaining Expression on De-identified Faces

© Springer International Publishing AG 2017The extensive use of video surveillance along with advances in face recognition has ignited concerns about the privacy of the people identifiable in the recorded documents. A face de-identification algorithm, named k-Same, has been proposed by prior research and guarantees to thwart face recognition software. However, like many previous attempts in face de-identification, kSame fails to preserve the utility such as gender and expression of the original data. To overcome this, a new algorithm is proposed here to preserve data utility as well as protect privacy. In terms of utility preservation, this new algorithm is capable of preserving not only the category of the facial expression (e.g., happy or sad) but also the intensity of the expression. This new algorithm for face de-identification possesses a great potential especially with real-world images and videos as each facial expression in real life is a continuous motion consisting of images of the same expression with various degrees of intensity.Peer reviewe

The Adiabatic Transport of Bose-Einstein Condensates in a Double-Well Trap: Case a Small Nonlinearity

A complete adiabatic transport of Bose-Einstein condensate in a double-well trap is investigated within the Landau-Zener (LZ) and Gaussian Landau-Zener (GLZ) schemes for the case of a small nonlinearity, when the atomic interaction is weaker than the coupling. The schemes use the constant (LZ) and time-dependent Gaussian (GLZ) couplings. The mean field calculations show that LZ and GLZ suggest essentially different transport dynamics. Significant deviations from the case of a strong coupling are discussed.Comment: 6 pages, 3 figures, to be published in Laser Physic

The conservation of energy-momentum and the mass for the graviton

In this work we give special attention to the bimetric theory of gravitation with massive gravitons proposed by Visser in 1998. In his theory, a prior background metric is necessary to take in account the massive term. Although in the great part of the astrophysical studies the Minkowski metric is the best choice to the background metric, it is not possible to consider this metric in cosmology. In order to keep the Minkowski metric as background in this case, we suggest an interpretation of the energy-momentum conservation in Visser's theory, which is in accordance with the equivalence principle and recovers naturally the special relativity in the absence of gravitational sources. Although we do not present a general proof of our hypothesis we show its validity in the simple case of a plane and dust-dominated universe, in which the `massive term' appears like an extra contribution for the energy density.Comment: 9 pages, accepted for publishing in GR

Creep strains predicted from constitutive equations for Zircaloy-clad spent fuel rods

Integrity of a high percentage of the Zircaloy (zirconium-alloy) clad spent fuel rods during extended dry storage is a design consideration of the storage system. Maintaining cladding integrity after permanent disposal placement may also be desired, although other barriers will be engineered to contain the radioactive waste. The limits to the temperatures the Zircaloy tubes can sustain over extended times are principally determined by creep at stresses (from internal gas pressure) and temperatures relevant to dry storage conditions. Excessive creep may lead to an eventual ductile fracture crack. The thermal design criteria assure compatibility of the heat load, the heat transfer properties, and the materials response. Therefore, the ability to predict the long-term integrity of Zircaloy is important to the design requirements. To do this reliably requires both a theoretical and empirical description of creep deformation and fracture