scholarly journals Investigation of heuristic search functions for nonlinear substitutions for symmetric cryptography

Radiotekhnika ◽  
2021 ◽  
pp. 53-63
Author(s):  
A.A. Kuznetsov ◽  
N.A. Poluyanenko ◽  
V.A. Katrich ◽  
S.O. Kandii ◽  
Yu.A. Zaichenko
Keyword(s):  
Heuristic Search ◽  
Input Data ◽  
Mathematical Problem ◽  
Hill Climbing ◽  
Symmetric Cryptography ◽  
Random Generation ◽  
Genetic Search ◽  
Computational Costs ◽  
The One ◽  
The Cost

Nonlinear substitutions (S-boxes) are used in most modern symmetric cryptoalgorithms. They are designed to mix input data and play a significant role in ensuring resistance against known cryptanalytic attacks (differential, linear, algebraic and other cryptanalysis methods). However, random generation of nonlinear substitutions with the desired indicators is an extremely difficult mathematical problem. This article explores the heuristic techniques for S-boxes informed search, in particular, discusses various cost functions used in most of the known algorithms (for example, local search, hill climbing, simulated annealing, genetic search, etc.). The aim of the study is to determine the specific parameters of heuristic functions, which, on the one hand, do not reduce the degree of awareness of the search nodes, and on the other hand, do not require significant computational costs. The article examines the influence of individual parameters on the value of the cost function and complexity of its calculation. It also provides specific recommendations for the formation of parameters for heuristic search for S-boxes, which significantly affect the efficiency of generating nonlinear substitutions for symmetric cryptography.

scholarly journals A Study on the Feasibility of Anaerobic Co-Digestion of Raw Cheese Whey with Coffee Pulp Residues

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3611
Author(s):  
Sandra Gonzalez-Piedra ◽  
Héctor Hernández-García ◽  
Juan M. Perez-Morales ◽  
Laura Acosta-Domínguez ◽  
Juan-Rodrigo Bastidas-Oyanedel ◽  
...  
Keyword(s):  
Methane Production ◽  
Kinetic Models ◽  
Cheese Whey ◽  
Maximum Yield ◽  
Gompertz Model ◽  
Coffee Pulp ◽  
The One ◽  
The Cost ◽  
Best Fit ◽  
Cheese Production

In this paper, a study on the feasibility of the treatment of raw cheese whey by anaerobic co-digestion using coffee pulp residues as a co-substrate is presented. It considers raw whey generated in artisanal cheese markers, which is generally not treated, thus causing environmental pollution problems. An experimental design was carried out evaluating the effect of pH and the substrate ratio on methane production at 35 °C (i.e., mesophilic conditions). The interaction of the parameters on the co-substrate degradation and the methane production was analyzed using a response surface analysis. Furthermore, two kinetic models were proposed (first order and modified Gompertz models) to determine the dynamic profiles of methane yield. The results show that co-digestion of the raw whey is favored at pH = 6, reaching a maximum yield of 71.54 mLCH4 gVSrem−1 (31.5% VS removed) for raw cheese whey and coffee pulp ratio of 1 gVSwhey gVSCoffe−1. The proposed kinetic models successfully fit the experimental methane production data, the Gompertz model being the one that showed the best fit. Then, the results show that anaerobic co-digestion can be used to reduce the environmental impact of raw whey. Likewise, the methane obtained can be integrated into the cheese production process, which could contribute to reducing the cost per energy consumption.

scholarly journals Electoral Incentives and the Allocation of Public Funds

2020 ◽  
Author(s):  
Frederico Finan ◽  
Maurizio Mazzocco
Keyword(s):  
Electoral System ◽  
Policy Reforms ◽  
Public Funds ◽  
Term Limit ◽  
The Public ◽  
Public Projects ◽  
Electoral Incentives ◽  
Using Data ◽  
The One ◽  
The Cost

Abstract Politicians allocate public resources in ways that maximize political gains, and potentially at the cost of lower welfare. In this paper, we quantify these welfare costs in the context of Brazil’s federal legislature, which grants its members a budget to fund public projects within their states. Using data from the state of Roraima, we estimate a model of politicians’ allocation decisions and find that 26.8% of the public funds allocated by legislators are distorted relative to a social planner’s allocation. We then use the model to simulate three potential policy reforms to the electoral system: the adoption of approval voting, imposing a one-term limit, and redistricting. We find that a one-term limit and redistricting are both effective at reducing distortions. The one-term limit policy, however, increases corruption, which makes it a welfare-reducing policy.

scholarly journals A MEAN FIELD GAME ANALYSIS OF SIR DYNAMICS WITH VACCINATION

2020 ◽  
pp. 1-18
Author(s):  
Josu Doncel ◽  
Nicolas Gast ◽  
Bruno Gaujal
Keyword(s):  
Mean Field ◽  
Vaccination Strategy ◽  
Game Analysis ◽  
Total Cost ◽  
Mean Field Game ◽  
Vaccination Behavior ◽  
Switching Curve ◽  
The One ◽  
The Cost ◽  
Vaccination Period

We analyze a mean field game model of SIR dynamics (Susceptible, Infected, and Recovered) where players choose when to vaccinate. We show that this game admits a unique mean field equilibrium (MFE) that consists in vaccinating at a maximal rate until a given time and then not vaccinating. The vaccination strategy that minimizes the total cost has the same structure as the MFE. We prove that the vaccination period of the MFE is always smaller than the one minimizing the total cost. This implies that, to encourage optimal vaccination behavior, vaccination should always be subsidized. Finally, we provide numerical experiments to study the convergence of the equilibrium when the system is composed by a finite number of agents ( $N$ ) to the MFE. These experiments show that the convergence rate of the cost is $1/N$ and the convergence of the switching curve is monotone.

scholarly journals HapSolo: an optimization approach for removing secondary haplotigs during diploid genome assembly and scaffolding

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Edwin A. Solares ◽  
Yuan Tao ◽  
Anthony D. Long ◽  
Brandon S. Gaut
Keyword(s):  
Cost Function ◽  
Anopheles Funestus ◽  
Hill Climbing ◽  
Optimization Approach ◽  
Sequencing Technology ◽  
Genome Data ◽  
A Genome ◽  
Long Read ◽  
Downstream Analysis ◽  
The Cost

Abstract Background Despite marked recent improvements in long-read sequencing technology, the assembly of diploid genomes remains a difficult task. A major obstacle is distinguishing between alternative contigs that represent highly heterozygous regions. If primary and secondary contigs are not properly identified, the primary assembly will overrepresent both the size and complexity of the genome, which complicates downstream analysis such as scaffolding. Results Here we illustrate a new method, which we call HapSolo, that identifies secondary contigs and defines a primary assembly based on multiple pairwise contig alignment metrics. HapSolo evaluates candidate primary assemblies using BUSCO scores and then distinguishes among candidate assemblies using a cost function. The cost function can be defined by the user but by default considers the number of missing, duplicated and single BUSCO genes within the assembly. HapSolo performs hill climbing to minimize cost over thousands of candidate assemblies. We illustrate the performance of HapSolo on genome data from three species: the Chardonnay grape (Vitis vinifera), with a genome of 490 Mb, a mosquito (Anopheles funestus; 200 Mb) and the Thorny Skate (Amblyraja radiata; 2650 Mb). Conclusions HapSolo rapidly identified candidate assemblies that yield improvements in assembly metrics, including decreased genome size and improved N50 scores. Contig N50 scores improved by 35%, 9% and 9% for Chardonnay, mosquito and the thorny skate, respectively, relative to unreduced primary assemblies. The benefits of HapSolo were amplified by down-stream analyses, which we illustrated by scaffolding with Hi-C data. We found, for example, that prior to the application of HapSolo, only 52% of the Chardonnay genome was captured in the largest 19 scaffolds, corresponding to the number of chromosomes. After the application of HapSolo, this value increased to ~ 84%. The improvements for the mosquito’s largest three scaffolds, representing the number of chromosomes, were from 61 to 86%, and the improvement was even more pronounced for thorny skate. We compared the scaffolding results to assemblies that were based on PurgeDups for identifying secondary contigs, with generally superior results for HapSolo.

Hiding Data in Plain Sight: Towards Provably Unbreakable Encryption with Short Secret Keys and One-Way Functions

2021 ◽  
Author(s):  
Mircea-Adrian Digulescu
Keyword(s):  
Encryption Scheme ◽  
Secret Key ◽  
Small Probability ◽  
Random Data ◽  
Computing Power ◽  
Plain Text ◽  
Secret Keys ◽  
The One ◽  
One Way Function ◽  
The Cost

It has long been known that cryptographic schemes offering provably unbreakable security exist, namely the One Time Pad (OTP). The OTP, however, comes at the cost of a very long secret key - as long as the plain-text itself. In this paper we propose an encryption scheme which we (boldly) claim offers the same level of security as the OTP, while allowing for much shorter keys, of size polylogarithmic in the computing power available to the adversary. The Scheme requires a large sequence of truly random words, of length polynomial in the both plain-text size and the logarithm of the computing power the adversary has. We claim that it ensures such an attacker cannot discern the cipher output from random data, except with small probability. We also show how it can be adapted to allow for several plain-texts to be encrypted in the same cipher output, with almost independent keys. Also, we describe how it can be used in lieu of a One Way Function.

scholarly journals Farm Gate Prices for Non-Varietal Wine in Argentina: A Multilevel Comparison of the Prices Paid by Cooperatives and Investor-Oriented Firms

2017 ◽  
Vol 16 (1) ◽  
Author(s):  
Agustina Malvido Perez Carletti ◽  
Markus Hanisch ◽  
Jens Rommel ◽  
Murray Fulton
Keyword(s):  
Multilevel Regression ◽  
Data Set ◽  
Unique Data ◽  
Market Shares ◽  
Price Effects ◽  
Theoretical Predictions ◽  
The One ◽  
The Cost ◽  
Price Differences ◽  
Multilevel Regression Model

AbstractIn this paper, we use a unique data set of the prices paid to farmers in Argentina for grapes to examine the prices paid by non-varietal wine processing cooperatives and investor-oriented firms (IOFs). Motivated by contrasting theoretical predictions of cooperative price effects generated by the yardstick of competition and property rights theories, we apply a multilevel regression model to identify price differences at the transaction level and the departmental level. On average, farmers selling to cooperatives receive a 3.4 % lower price than farmers selling to IOFs. However, we find cooperatives pay approximately 2.4 % more in departments where cooperatives have larger market shares. We suggest that the inability of cooperatives to pay a price equal to or greater than the one paid by IOFs can be explained by the market structure for non-varietal wine in Argentina. Specifically, there is evidence that cooperative members differ from other farmers in terms of size, assets and the cost of accessing the market. We conclude that the analysis of cooperative pricing cannot solely focus on the price differential between cooperatives and IOFs, but instead must consider other factors that are important to the members.

The ‘Pistola’ of Cerveri de Girona

Traditio ◽  
1948 ◽  
Vol 6 ◽  
pp. 161-185
Author(s):  
Kurt Lewent
Keyword(s):  
The Other ◽  
Love Affair ◽  
Other Hand ◽  
Good Taste ◽  
Moral Argumentation ◽  
The Subject ◽  
Way Of Thinking ◽  
The One ◽  
The Cost ◽  
Troubadour Poetry

Cerveri was decidedly no poetical genius, and often enough he follows the trodden paths of troubadour poetry. However, there is no denying that again and again he tries to escape that poetical routine. In many cases these attempts result in odd and eccentric compositions, where the unusual is reached at the cost of good taste and poetical values. On the other hand, it must be admitted that Cerveri's efforts in this respect were not always futile. His is, e.g. an amusing satire upon bad women. One of his love songs, characteristically called libel by the MS (Sg), assumes the form of a complaint submitted to the king as the supreme earthly judge, in which the defendant is the lady whose charms torture the lover and have made him a prisoner. This poem combines the traditional praise of the beloved and a flattery addressed to the king. Its slightly humoristic tone is also found in a song entitled lo vers del vassayll leyal. Here Cerveri, basing himself on a certain legend connected with St. Mark, gives the king advice in his love affair. Again the poet kills two birds with one stone, flattering the sovereign and pointing, for obvious purposes, to his own poverty. The latter is the only topic of a remarkably personal poem in which the author complains bitterly that, while many of his playmates have become rich in later years, the only wealth he himself did amass were the chans gays and sonetz agradans which he composed for other people to enjoy. Cerveri even tries to renew the traditional genre of the chanson de la mal mariée by adding motifs of—presumably—his own invention. This tendency towards a more independent way of thinking and greater originality in its poetical presentation could not be better illustrated than by the two poems which the MS calls Lo vers de la terra de Preste Johan and Pistola The one puts the poet's moral argumentation against the background of the medieval legend of Prester John, the other, which forms the subject of the present study, sets its teachings in a still more solemn framework, the liturgy of the Mass.

The Development of the Traction Drive Mechanism Made of the Plastic Magnet

2003 ◽  
Author(s):  
Akira Shoji ◽  
Giichi Kawashima
Keyword(s):  
Magnetic Induction ◽  
Ferrite Powder ◽  
Traction Drive ◽  
Drive Mechanism ◽  
Hard Magnet ◽  
The One ◽  
The Cost ◽  
Outside Diameter ◽  
As If

This paper is the one that it was described to have developed the traction drive by using the plastic hard magnet. The plastics material was used to research by the following reasons. The plastics material can mold it. As a result, it processes complex and it is possible to make it to the magnet. In addition, it is possible to mass-produce, it is light, and it is also possible that the miniaturization reduces possible and the cost. Next, the mechanism of the traction drive is described. It rotates by being circumscribed by non-contact, and inscribing two plastic hard rings as if the gear. N pole and S pole are divided equally in the direction of the circumference of the ring. It becomes by these as if the match of the god with teeth and teeth. These devices are commonly called “Gear without teeth”. Some doughnut disks with a different outside diameter were produced. Each disk is made magnetism. Each disk was set, and assembled to one disk. The disk is molded with the plastic hard. The plastics material used the one that the ferrite powder was mixed with the polyacetal resin. Making to magnetism is possible by the magnetization technology. The mechanism, molding, making to magnetism, and the magnetic induction, etc. were examined in the experiment. The development of non-contact made of plastic hard traction drive device was proven to be possible by this research.

scholarly journals Performance Comparative Analysis of Monocrystalline and Polycrystalline Single Diode Solar Panel Models using the Five Parameters Method

2019 ◽  
Vol 1 (1) ◽  
pp. 14
Author(s):  
Rizal Akbarudin Rahman ◽  
Aripriharta Aripriharta ◽  
Hari Putranto
Keyword(s):  
Renewable Energy ◽  
Input Data ◽  
Power Plants ◽  
Renewable Energy Sources ◽  
Solar Panel ◽  
Solar Panels ◽  
Natural Conditions ◽  
Panel Models ◽  
The Cost ◽  
Module Performance

The use of renewable energy as a source of electrical energyincreases every year. Unfortunately, Indonesia does not have manypower plants that utilize renewable energy sources. The mostpotential renewable energy in Indonesia is the sunlight with the helpof solar panels that converts solar energy into electrical energy.However, the environment could affect the solar panel module andin turn, affect the performance of solar panels or the generatedelectric energy. This research calculated the performance of solarpanels with a single-diode model using the Five Parameters methodthat required solar panel module specification data, the totalradiation absorbed by the solar panel module, and the temperatureof the environment. The Five Parameters method is a methodmodeled after solar panel module performance in the form of thesingle-diode equivalent circuit. The Five Parameters method isreliable in predicting the energy produced by the solar panels whenthe input data is limited. The results for using the Five Parametersin monocrystalline solar panels were Isc = 1.827 A, Imp = 0.662 A,Voc = 18.221 V, Vmp = 15.019 V, Pmp = 9.955 W. And the results inpolycrystalline solar panels were Isc = 1.926 A, Imp = 0.686 A, Voc =17.594 V, Vmp = 14.166 V, Pmp = 9.722 W. Based on the results; itwas concluded that the most efficient and optimised types of solarpanels on natural conditions in Sendang Biru Beach was themonocrystalline solar panel because it produced electrical outputpower of 9.955 W. Therefore, there could be a manufacturer ofsolar energy power plants to reduce the cost of electricity in thecoastal area, such as in Sendang Biru Beach.

scholarly journals Adam Smith’s concept of labour: value or measure?

2016 ◽  
Vol 34 (2) ◽  
pp. 152-165
Author(s):  
Adolfo Rodríguez Herrera
Keyword(s):  
Karl Marx ◽  
John Stuart Mill ◽  
Production Theory ◽  
Real Price ◽  
Cost Of Production ◽  
Theory Of Value ◽  
The One ◽  
The Cost ◽  
David Ricardo

Smith is considered the father of the labour theory of value developed by David Ricardo and Karl Marx and simultaneously of the cost-of-production theory of value developed by John Stuart Mill and Alfred Marshall. This polysemy is partly because Smith is developping the terminology to refer to value and measure of value, and often uses it with much imprecision. That has led to different interpretations about his position on these issues, most of them derived from an error of interpretation of Ricardo and Marx. This paper reviews the concepts developed by Smith to formulate his theory of value (value, real price and exchangeable value). Our interpretation of his texts on value does not coincide with what has traditionally been done. According to our interpretation, it would not be correct the criticism made by Ricardo and Marx on Smith’s position about the role of labour as measure of value. For these authors, Smith is not consistent in proposing that the value of a commodity is defined or measured as the amount of labour necessary to produce it and simultaneously as the amount of labour that can be purchased by this commodity. We try to show that for Smith the labour has a double role –as source and measure of value–, and that to it is due the confusion that generates his use of some terms: Smith proposes labour as a measure of value because he conceives it as a source of value. With this interpretation it becomes clear, paradoxically, that Smith holds a labour theory of value that substantially corresponds to the one later developed by Ricardo and Marx.

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