scholarly journals Optimizing GOST R 34.12 "Magma" Algorithms for 8-Bit Microcontrollers

Author(s):  
E. Yu. Shtanov ◽  
M. V. Polyakov

The paper concentrates on development of optimizing methods for the GOST R 34.12-2015 "Magma" cipher algorithm when it is implemented on 8-bit microcontrollers. There is a number of techniques in the paper, which being used, allow you to create the specialized implementations of the algorithm: 1) focused on the operation speed; 2) focused on reducing the memory used; 3) optimal which involves the best solutions based on two previous implementations. Each optimization method is represented by description and performance indicators of the results obtained in comparison with the direct implementation of the algorithm. So, in the case of optimal algorithm implementation the enciphering process is 11 times accelerated, and an amount of the occupied memory is 1/32 of the microcontroller's memory. The built-in compiler tools were used to optimize the software code. The techniques described are applicable to any 8-bit platform.

Author(s):  
Edoardo Fadda ◽  
Daniele Manerba ◽  
Gianpiero Cabodi ◽  
Paolo Enrico Camurati ◽  
Roberto Tadei

Author(s):  
Kersten Schuster ◽  
Philip Trettner ◽  
Leif Kobbelt

We present a numerical optimization method to find highly efficient (sparse) approximations for convolutional image filters. Using a modified parallel tempering approach, we solve a constrained optimization that maximizes approximation quality while strictly staying within a user-prescribed performance budget. The results are multi-pass filters where each pass computes a weighted sum of bilinearly interpolated sparse image samples, exploiting hardware acceleration on the GPU. We systematically decompose the target filter into a series of sparse convolutions, trying to find good trade-offs between approximation quality and performance. Since our sparse filters are linear and translation-invariant, they do not exhibit the aliasing and temporal coherence issues that often appear in filters working on image pyramids. We show several applications, ranging from simple Gaussian or box blurs to the emulation of sophisticated Bokeh effects with user-provided masks. Our filters achieve high performance as well as high quality, often providing significant speed-up at acceptable quality even for separable filters. The optimized filters can be baked into shaders and used as a drop-in replacement for filtering tasks in image processing or rendering pipelines.


2021 ◽  
Vol 13 (12) ◽  
pp. 2342
Author(s):  
Jin-Bong Sung ◽  
Sung-Yong Hong

A new method to design in-orbit synthetic aperture radar operational parameters has been implemented for the Korean Multi-purpose Satellite 6 mission. The implemented method optimizes the pulse repetition frequency when a satellite altitude changes from its nominal one, so it has the advantage that the synthetic aperture radar performances can satisfy the requirements for the in-orbit operation. Other commanding parameters have been designed to conduct trade-off between those parameters. This paper presents the new optimization method to maintain the synthetic aperture radar performances even in the case of an altitude variation. Design methodologies to determine operational parameters, respectively, at nominal altitude and in orbit are presented. In addition, numerical simulation is presented to validate the proposed optimization and the design methodologies.


Author(s):  
Alois Paulin

In this study the authors analyze the effects of e-government reforms that began in mid-90ies by confronting the promises which these reforms made to government performance in the period before and after the reforms took place. The authors use fiscal and performance indicators of the Slovenian government and courts to argue that e-government did not yield any notable effects on the state performance. Finally, the authors analyze the reasons why e-government technology cannot be regarded as sustainable and suggest a different approach towards researching how to sustainably improve governance for generations to come.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Zhao Wu ◽  
Naixue Xiong ◽  
Yannong Huang ◽  
Qiong Gu ◽  
Chunyang Hu ◽  
...  

At present the cloud computing is one of the newest trends of distributed computation, which is propelling another important revolution of software industry. The cloud services composition is one of the key techniques in software development. The optimization for reliability and performance of cloud services composition application, which is a typical stochastic optimization problem, is confronted with severe challenges due to its randomness and long transaction, as well as the characteristics of the cloud computing resources such as openness and dynamic. The traditional reliability and performance optimization techniques, for example, Markov model and state space analysis and so forth, have some defects such as being too time consuming and easy to cause state space explosion and unsatisfied the assumptions of component execution independence. To overcome these defects, we propose a fast optimization method for reliability and performance of cloud services composition application based on universal generating function and genetic algorithm in this paper. At first, a reliability and performance model for cloud service composition application based on the multiple state system theory is presented. Then the reliability and performance definition based on universal generating function is proposed. Based on this, a fast reliability and performance optimization algorithm is presented. In the end, the illustrative examples are given.


2021 ◽  
Vol 23 (3) ◽  
pp. 33-38
Author(s):  
VALERYA DAMBUEVA ◽  

The article analyses various approaches to assessing the PR activities of commercial organizations and public authorities. The author concludes that there is no comprehensive methodology for analyzing and evaluating the effectiveness of PR activities. This indicates the relevance and the need to develop a special methodology to identify relevant and potential sources for the formation and development of a complex image and reputation characteristics of public authorities with which citizens of the Russian Federation could operate. The basis of the proposed theory is the materials of works on communication by G. Lasswell (model of mass communication, pentad). The method is a system of evaluation parameters, performance indicators, and analytical tools for each structural component of such activities, as well as an algorithm for their analysis and evaluation. When developing this methodology, we try to take into account the maximum number of criteria and performance indicators, but in practice, it is not always possible. To increase the effectiveness of the methodology, the author conducts the structuring of the pentad, which allows to distinguish the main processes of PR activity of a public authority. The assessment of each component of the pentad is a separate study in which we can identify the relevant PR activity processes that require adjustment.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yazan Khalid Abed-Allah Migdadi

Purpose This study aims to identify the effective operational strategies for airlines in a pandemic that allow them to recover and bounce back smoothly. Design/methodology/approach This study adopted quantitative methodology based on secondary data published by the airlines related to operational and performance indicators. The total number of airlines surveyed was 145. The sample of study covers all the following regions: Africa, Asia, Europe, the Middle East, North America and South America. The data analysis of this research passed through several phases to compare the situation before and during pandemic period. Findings The effective operational strategy patterns during the outbreak of the COVID-19 pandemic comprise three hybrid strategies and one scheduling strategy. It appears from these strategy models that four strategic alternatives are available for international airlines to adopt, while two strategic alternatives are available for regional airlines. The strategy alternatives for regional and international airlines are all effective, but those of the international airlines are the more effective ones. Originality/value Previous studies rarely adopted the theory of operations strategy configuration (emphasizing taxonomies-based perspective) and the organizational resilience theory (emphasizing capability-based perspective) to identify the effective airlines operations strategy patterns in a pandemic, that allow airlines to recover and bounce back smoothly by analyzing the practices of airlines from different geographic regions worldwide.


Author(s):  
Xabier Muriel ◽  
Pedro L. Valenzuela ◽  
Manuel Mateo-March ◽  
Jesús G. Pallarés ◽  
Alejandro Lucia ◽  
...  

Purpose: To compare the physical demands and performance indicators of male professional cyclists of 2 different categories (Union Cycliste Internationale WorldTour [WT] and ProTeam [PT]) during a cycling grand tour. Methods: A WT team (n = 8, 31.4 [5.4] y) and a PT team (n = 7, 26.9 [3.3] y) that completed “La Vuelta 2020” volunteered to participate. Participants’ power output (PO) was registered, and measures of physical demand and physiological performance (kilojoules spent, training stress score, time spent at different PO bands/zones, and mean maximal PO [MMP] for different exertion durations) were computed. Results: WT achieved a higher final individual position than PT (31 [interquartile range = 33] vs 71 [59], P = .004). WT cyclists showed higher mean PO and kilojoule values than their PT peers and spent more time at high-intensity PO values (>5.25 W·kg−1) and zones (91%–120% of individualized functional threshold power) (Ps < .05). Although no differences were found for MMP values in the overall analysis (P > .05), subanalyses revealed that the between-groups gap increased through the race, with WT cyclists reaching higher MMP values for ≥5-minute efforts in the second and third weeks (Ps < .05). Conclusions: Despite the multifactorial nature of cycling performance, WT cyclists spend more time at high intensities and show higher kilojoules and mean PO than their PT referents during a grand tour. Although the highest MMP values attained during the whole race might not differentiate between WT and PT cyclists, the former achieve higher MMP values as the race progresses.


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