5,377 research outputs found

    Correlation between the golden ratio and nanowire transistor performance

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    An observation was made in this research regarding the fact that the signatures of isotropic charge distributions in silicon nanowire transistors (NWT) displayed identical characteristics to the golden ratio (Phi). In turn, a simulation was conducted regarding ultra-scaled n-type Si (NWT) with respect to the 5-nm complementary metal-oxide-semiconductor (CMOS) application. The results reveal that the amount of mobile charge in the channel and intrinsic speed of the device are determined by the device geometry and could also be correlated to the golden ratio (Phi). This paper highlights the issue that the optimization of NWT geometry could reduce the impact of the main sources of statistical variability on the Figure of Merit (FoM) of devices. In the context of industrial early successes in fabricating vertically stacked NWT, ensemble Monte Carlo (MC) simulations with quantum correction are used to accurately predict the drive current. This occurs alongside a consideration of the degree to which the carrier transport in the vertically stacked lateral NWTs are complex

    Why Just Boogie? Translating Between Intermediate Verification Languages

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    The verification systems Boogie and Why3 use their respective intermediate languages to generate verification conditions from high-level programs. Since the two systems support different back-end provers (such as Z3 and Alt-Ergo) and are used to encode different high-level languages (such as C# and Java), being able to translate between their intermediate languages would provide a way to reuse one system's features to verify programs meant for the other. This paper describes a translation of Boogie into WhyML (Why3's intermediate language) that preserves semantics, verifiability, and program structure to a large degree. We implemented the translation as a tool and applied it to 194 Boogie-verified programs of various sources and sizes; Why3 verified 83% of the translated programs with the same outcome as Boogie. These results indicate that the translation is often effective and practically applicable

    Comparison of techniques for estimating the frequency selectivity of bandlimited channels

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    A transmission channel used in application such as telecommunications can be modeled as a bandpass filter. Measurement of the frequency selectivity of the channel is important to ensure that the information-bearing signal has minimal distortion and loss of information. A comparison is made for several methods used for estimating the frequency selectivity of the transmission. The methods presented are the correlation method, instantaneous energy and frequency estimation and the cross Wigner-Ville distribution. The theoretical foundations and assumptions are described for each method. In general, all the methods gave similar performance in terms of the frequency selectivity. Due to the shorter analysis duration, both the instantaneous energy and frequency estimation and cross Wigner-Ville distribution is ideal for estimating the frequency selectivity of time-varying channel

    Study of Locating Fire Stations using Linear Assignment Method : Case Study Maku City

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    Today excess density of population in city and it is increasing growth in bulk is led to demand and attention to urban development Demand for urban development is one of the most important issues against human in future Therefore to solve this problem and obstacles safety system of city should be developed along this to cover whole city The most important problem about the services of fire stations is the inappropriate distribution of stations and restricted function area of present stations So qualities and quantities distribution of stations is investigated scientifically and professionally Using traditional methods planning fire stations for services mean wasting papers and time but today using GIS serves as a tool to create proper and effective databas

    The rate of the prevalence of high-risk pregnancies and the results on pregnant mothers and the effect on parameters after the birth

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    Pregnancy causes large physiologic changes in most body systems and these changes may lead to ease or harden examining some events. The purpose of this study is to define the rate of risk in pregnant women and the results in mother and fetus and also to define the risk rate of pregnancy in pregnant women and its effect on parameters after birth in patients of Educational and Medical center of Gorgan, Dezyani. This case - control study was performed in Educational and Medical Center Dezyany, of Golestan University of Medical Sciences in 1390. In this study, 1266 pregnant women were enrolled of which 804 cases (63.5%) according to the criteria for scoring in the questionnaire with a score greater than or equal to 7 were considered as high risk pregnancies (case group), 462 patients (36.5%) were considered as low-risk pregnancies (control group). Parameters after the birth and pregnancy results such as delivery type, infant difficulties, mother health after labor were compared and analyzed by T-test and ANOVA in both groups. About the history of infertility almost 80% of the people who had a 2-year history of infertility were in high-risk group and the difference was significant. (P = 0.02) About the history of abortion also almost 90% of the people who had a 2-year history of abortion were in highrisk group and the difference was significant. (P<0.05) Post-term infant was found in 77 cases that were entirely in high-risk group. This difference was statistically significant (P<0.05). According to results and comparing them to other studies we can conclude that pregnant mothers who have pregnancy difficulties history such as history of abortion or infertility, visits during pregnancy should be paid attention and warn them about the risk of not being visited and timely pursuits

    Computationally Data-Independent Memory Hard Functions

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    Memory hard functions (MHFs) are an important cryptographic primitive that are used to design egalitarian proofs of work and in the construction of moderately expensive key-derivation functions resistant to brute-force attacks. Broadly speaking, MHFs can be divided into two categories: data-dependent memory hard functions (dMHFs) and data-independent memory hard functions (iMHFs). iMHFs are resistant to certain side-channel attacks as the memory access pattern induced by the honest evaluation algorithm is independent of the potentially sensitive input e.g., password. While dMHFs are potentially vulnerable to side-channel attacks (the induced memory access pattern might leak useful information to a brute-force attacker), they can achieve higher cumulative memory complexity (CMC) in comparison than an iMHF. In particular, any iMHF that can be evaluated in N steps on a sequential machine has CMC at most ?((N^2 log log N)/log N). By contrast, the dMHF scrypt achieves maximal CMC ?(N^2) - though the CMC of scrypt would be reduced to just ?(N) after a side-channel attack. In this paper, we introduce the notion of computationally data-independent memory hard functions (ciMHFs). Intuitively, we require that memory access pattern induced by the (randomized) ciMHF evaluation algorithm appears to be independent from the standpoint of a computationally bounded eavesdropping attacker - even if the attacker selects the initial input. We then ask whether it is possible to circumvent known upper bound for iMHFs and build a ciMHF with CMC ?(N^2). Surprisingly, we answer the question in the affirmative when the ciMHF evaluation algorithm is executed on a two-tiered memory architecture (RAM/Cache). We introduce the notion of a k-restricted dynamic graph to quantify the continuum between unrestricted dMHFs (k=n) and iMHFs (k=1). For any ? > 0 we show how to construct a k-restricted dynamic graph with k=?(N^(1-?)) that provably achieves maximum cumulative pebbling cost ?(N^2). We can use k-restricted dynamic graphs to build a ciMHF provided that cache is large enough to hold k hash outputs and the dynamic graph satisfies a certain property that we call "amenable to shuffling". In particular, we prove that the induced memory access pattern is indistinguishable to a polynomial time attacker who can monitor the locations of read/write requests to RAM, but not cache. We also show that when k=o(N^(1/log log N))then any k-restricted graph with constant indegree has cumulative pebbling cost o(N^2). Our results almost completely characterize the spectrum of k-restricted dynamic graphs
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