scholarly journals NOCAS : A Nonlinear Cellular Automata Based Stream Cipher

2011 ◽  
Vol DMTCS Proceedings vol. AP,... (Proceedings) ◽  
Author(s):  
Sandip Karmakar ◽  
Dipanwita Roy Chowdhury
Keyword(s):  
Cellular Automata ◽  
Stream Cipher ◽  
State Of The Art ◽  
Building Blocks ◽  
The State ◽  
Stream Ciphers ◽  
Initialization Vector ◽  
International Audience ◽  
Suitable Structure ◽  
Almost All

International audience LFSR and NFSR are the basic building blocks in almost all the state of the art stream ciphers like Trivium and Grain-128. However, a number of attacks are mounted on these type of ciphers. Cellular Automata (CA) has recently been chosen as a suitable structure for crypto-primitives. In this work, a stream cipher is presented based on hybrid CA. The stream cipher takes 128 bit key and 128 bit initialization vector (IV) as input. It is designed to produce $\mathrm{2^{128}}$ random keystream bits and initialization phase is made faster 4 times than that of Grain-128. We also analyze the cryptographic strength of this cipher. Finally, the proposed cipher is shown to be resistant against known existing attacks.

An experimental study on feature-based SLAM for multi-legged robots with RGB-D sensors

2017 ◽  
Vol 44 (4) ◽  
pp. 428-441 ◽  
Author(s):  
Michał R. Nowicki ◽  
Dominik Belter ◽  
Aleksander Kostusiak ◽  
Petr Cížek ◽  
Jan Faigl ◽  
...  
Keyword(s):  
Performance Metrics ◽  
State Of The Art ◽  
Building Blocks ◽  
Bundle Adjustment ◽  
The State ◽  
Legged Robots ◽  
Evaluation Methodology ◽  
Walking Robots ◽  
Content Type ◽  
Feature Based

Purpose This paper aims to evaluate four different simultaneous localization and mapping (SLAM) systems in the context of localization of multi-legged walking robots equipped with compact RGB-D sensors. This paper identifies problems related to in-motion data acquisition in a legged robot and evaluates the particular building blocks and concepts applied in contemporary SLAM systems against these problems. The SLAM systems are evaluated on two independent experimental set-ups, applying a well-established methodology and performance metrics. Design/methodology/approach Four feature-based SLAM architectures are evaluated with respect to their suitability for localization of multi-legged walking robots. The evaluation methodology is based on the computation of the absolute trajectory error (ATE) and relative pose error (RPE), which are performance metrics well-established in the robotics community. Four sequences of RGB-D frames acquired in two independent experiments using two different six-legged walking robots are used in the evaluation process. Findings The experiments revealed that the predominant problem characteristics of the legged robots as platforms for SLAM are the abrupt and unpredictable sensor motions, as well as oscillations and vibrations, which corrupt the images captured in-motion. The tested adaptive gait allowed the evaluated SLAM systems to reconstruct proper trajectories. The bundle adjustment-based SLAM systems produced best results, thanks to the use of a map, which enables to establish a large number of constraints for the estimated trajectory. Research limitations/implications The evaluation was performed using indoor mockups of terrain. Experiments in more natural and challenging environments are envisioned as part of future research. Practical implications The lack of accurate self-localization methods is considered as one of the most important limitations of walking robots. Thus, the evaluation of the state-of-the-art SLAM methods on legged platforms may be useful for all researchers working on walking robots’ autonomy and their use in various applications, such as search, security, agriculture and mining. Originality/value The main contribution lies in the integration of the state-of-the-art SLAM methods on walking robots and their thorough experimental evaluation using a well-established methodology. Moreover, a SLAM system designed especially for RGB-D sensors and real-world applications is presented in details.

The State of the Art in Management Education Applicable to Aerospace Activities

1967 ◽  
Vol 71 (677) ◽  
pp. 342-343
Author(s):  
F. H. East
Keyword(s):  
Research And Development ◽  
Management Education ◽  
State Of The Art ◽  
Development Project ◽  
The State ◽  
The Other ◽  
The Past ◽  
Defence Budget ◽  
The One ◽  
Almost All

The Aviation Group of the Ministry of Technology (formerly the Ministry of Aviation) is responsible for spending a large part of the country's defence budget, both in research and development on the one hand and production or procurement on the other. In addition, it has responsibilities in many non-defence fields, mainly, but not exclusively, in aerospace.Few developments have been carried out entirely within the Ministry's own Establishments; almost all have required continuous co-operation between the Ministry and Industry. In the past the methods of management and collaboration and the relative responsibilities of the Ministry and Industry have varied with time, with the type of equipment to be developed, with the size of the development project and so on. But over the past ten years there has been a growing awareness of the need to put some system into the complex business of translating a requirement into a specification and a specification into a product within reasonable bounds of time and cost.

scholarly journals Performance and Statistical Analysis of Stream ciphers in GSM Communications

2020 ◽  
Vol 16 (1) ◽  
pp. 11-18 ◽  
Author(s):  
Nagendar Yerukala ◽  
V Kamakshi Prasad ◽  
Allam Apparao
Keyword(s):  
Statistical Analysis ◽  
Stream Cipher ◽  
Statistical Tests ◽  
Stream Ciphers ◽  
Test Suite ◽  
Secret Key ◽  
Initial State ◽  
Detailed Statistical Analysis ◽  
Almost All ◽  
The Given

For a stream cipher to be secure, the keystream generated by it should be uniformly random with parameter 1/2.Statistical tests check whether the given sequence follow a certain probability distribution. In this paper, we perform a detailed statistical analysis of various stream ciphers used in GSM 2G,3G, 4G and 5G communications. The sequences output by these ciphers are checked for randomness using the statistical tests defined by the NIST Test Suite. It should also be not possible to derive any information about secret key and the initial state ofthe cipher from the keystream. Therefore, additional statisticaltests based on properties like Correlation between Keystreamand Key, and Correlation between Keystream and IV are also performed. Performance analysis of the ciphers also has been done and the results tabulated. Almost all the ciphers pass thetests in the NIST test suite with 99% confidence level. For A5/3stream cipher, the correlation between the keystream and key is high and correlation between the keystream and IV is low when compared to other ciphers in the A5 family.

Patterns of Development of Family Businesses in Italy

1995 ◽  
Vol 8 (4) ◽  
pp. 255-265 ◽  
Author(s):  
Guido Corbetta
Keyword(s):  
Empirical Research ◽  
State Of The Art ◽  
Family Businesses ◽  
The State ◽  
International Audience

Italy is characterized by a considerable presence of small-, medium-, and even large-sized family businesses. After identifying four types of family businesses, this article analyzes three patterns of development: managerialization, the rise in the number of family partners, and the opening of the capital to nonfamily partners. The article, based on empirical research involving almost seventy Italian enterprises of various sizes, aims at informing an international audience of the state of the art of family businesses in Italy.

scholarly journals Pluralidad y lagunas jurídicas en ecoleyes relacionadas con áreas naturales protegidas de competencia estatal en México

2018 ◽  
Vol 30 (72) ◽  
Author(s):  
Jesús Ignacio Castro Salazar ◽  
Rodrigo Tovar Cabañas
Keyword(s):  
Content Analysis ◽  
State Of The Art ◽  
The State ◽  
Natural Areas ◽  
Conceptual Approach ◽  
Protected Natural Areas ◽  
Almost All

En este artículo se diserta sobre la pluralidad y las lagunas jurídicas en las áreas naturales protegidas en México, por considerarlas un instrumento de conservación clave para cientos de especies y ecosistemas. El estudio se realizó a escala nacional con base en la legislación vigente hasta finales de 2015, con el objetivo de identificar las lagunas legales relacionadas con dichas áreas; primero se presenta el estado del arte y el enfoque teórico-conceptual que guió al estudio, y luego se describe la metodología empleada, basada principalmente en análisis de contenido. También se muestran los resultados y las discusiones sobre la pluralidad de las leyes en la materia, y además las lagunas existentes en ellas. Entre los primeros destaca que, a pesar de que en casi todos los estados hay áreas naturales protegidas, la mayoría no cuenta con leyes para su regulación, y también sobresale que muchas autorizan el autoconsumo, aunque no lo definen.Plurality and legal loopholes in eco-laws related to protected natural areas within state jurisdiction in MexicoThis article discusses plurality and legal loopholes in pro­tected natural areas in Mexico, considering them a key tool for the conservation of hundreds of species and ecosystems. Based on the legislation in force until the end of 2015, the study was carried out on a nationwide scale in order to iden­tify legal loopholes related to these areas. Firstly, the state of the art and the theoretical-conceptual approach guid­ing the study are presented; then the methodology used, based mainly on content analysis, is described. Likewise, re­sults and discussions on plurality of laws in this regard are shown, as well as loopholes existing in them. Among the first ones, it should be noted that, even though in almost all states there are protected natural areas, most of them do not have laws regulating these areas. Also, many of them autho­rize self-consumption, without defining it.

scholarly journals Ceriantharia (Cnidaria) of the World: an annotated catalogue and key to species

ZooKeys ◽  
2020 ◽  
Vol 952 ◽  
pp. 1-63 ◽  
Author(s):  
Sérgio N. Stampar ◽  
James D. Reimer ◽  
Maximiliano M. Maronna ◽  
Celine S. S. Lopes ◽  
Hellen Ceriello ◽  
...  
Keyword(s):  
Species Identification ◽  
State Of The Art ◽  
The State ◽  
Complete List ◽  
Valid Species ◽  
Taxonomic Identification ◽  
Key To Species ◽  
Adult Form ◽  
The World ◽  
Almost All

The diversity of Ceriantharia is known from studies formally describing species from the late 18th Century onwards. However, no nomenclators including a list and discussion of all valid species have been produced since a list discussed by Carlgren in 1912. The present nomenclator presents a complete list of adult species of Ceriantharia of the World, including a discussion on each species. It includes the three families (Arachnactidae, Botrucnidiferidae, Cerianthidae) and the currently accepted 54 species based on their adult form. This study serves as a presentation of the “state-of-the-art” list of species of Ceriantharia, and includes a species identification key to support taxonomic identification. Additional in-depth species-by-species investigations for almost all cerianthid species is still needed, as the information available for most of these species is quite superficial.

scholarly journals Persuasive Technology and Energy: critical analysis of the state of the art

2015 ◽  
Vol Volume 4, Number 1, Special... (Special Issue...) ◽  
Author(s):  
Grégory Cano ◽  
Yann Laurillau ◽  
Gaëlle Calvary
Keyword(s):  
Energy Consumption ◽  
Critical Analysis ◽  
Design Space ◽  
State Of The Art ◽  
Persuasive Technology ◽  
The State ◽  
Systematic Analysis ◽  
Persuasive Technologies ◽  
International Audience ◽  
Six Dimensions

International audience This paper presents a state of the art and an analysis of existing works dedicated to persuasive technologies for energy consumption. Thanks to a systematic analysis, a set of concepts of persuasion has been identified and organized into a six dimensional design space. In particular, the concept of persuasion function is identified and defined. Six persuasion functions are identified: Mirror, Explain, Recommend, What-if, What-for, Suggest-and-Adjust. This design space is used to characterize the works considered in this state of the art. Cet article dresse un état de l’art et une analyse critique des travaux menés sur la persuasion technologique dans le cadre de la consommation énergétique. De cette analyse systématique est extrait un panel des concepts de persuasion ensuite organisé au sein d’un espace de classification comportant six dimensions dont le concept de fonction de persuasion. En particulier, six fonctions de persuasion sont identifiées et caractérisées : Mirror, Explain, Recommend, What-if, What-for, Suggest- and-Adjust. Cet espace de classification permet de caractériser les travaux de l’art.

scholarly journals On the calculation of the linear equivalence bias of jump controlled linear finite state machines

2010 ◽  
Vol 45 (1) ◽  
pp. 51-63
Author(s):  
Cees J. A. Jansen
Keyword(s):  
Finite State Machine ◽  
Stream Cipher ◽  
Finite State Machines ◽  
Building Blocks ◽  
Stream Ciphers ◽  
Side Channel ◽  
State Machines ◽  
Exponential Order ◽  
Low Degree ◽  
Finite State

ABSTRACT Jump controlled linear finite state machines were introduced several years ago as building blocks for stream ciphers that can efficiently be implemented in hardware and have intrinsically good side channel resistance. These constructions have found their way in concrete stream cipher designs. The bias in the distribution of linear relations of low degree in the key stream is important for the cryptographic strength of these stream ciphers. Recently, an algorithm was presented by the author to determine this bias. In this paper a new algorithm is introduced, that makes use of the properties of jump registers and has sub exponential order in the degree of the characteristic polynomial of the linear finite state machine.

scholarly journals Optimizing Implementations of Lightweight Building Blocks

2017 ◽  
pp. 130-168 ◽  
Author(s):  
Jérémy Jean ◽  
Thomas Peyrin ◽  
Siang Meng Sim ◽  
Jade Tourteaux
Keyword(s):  
State Of The Art ◽  
Building Blocks ◽  
The State ◽  
Fine Tuning ◽  
Implementation Cost ◽  
Cryptographic Primitives ◽  
Small Functions ◽  
Hardware Implementations ◽  
Non Linear

We study the synthesis of small functions used as building blocks in lightweight cryptographic designs in terms of hardware implementations. This phase most notably appears during the ASIC implementation of cryptographic primitives. The quality of this step directly affects the output circuit, and while general tools exist to carry out this task, most of them belong to proprietary software suites and apply heuristics to any size of functions. In this work, we focus on small functions (4- and 8-bit mappings) and look for their optimal implementations on a specific weighted instructions set which allows fine tuning of the technology. We propose a tool named LIGHTER, based on two related algorithms, that produces optimized implementations of small functions. To demonstrate the validity and usefulness of our tool, we applied it to two practical cases: first, linear permutations that define diffusion in most of SPN ciphers; second, non-linear 4-bit permutations that are used in many lightweight block ciphers. For linear permutations, we exhibit several new MDS diffusion matrices lighter than the state-of-the-art, and we also decrease the implementation cost of several already known MDS matrices. As for non-linear permutations, LIGHTER outperforms the area-optimized synthesis of the state-of-the-art academic tool ABC. Smaller circuits can also be reached when ABC and LIGHTER are used jointly.

Advanced separators based on aramid nanofiber (ANF) membranes for lithium-ion batteries: a review of recent progress

2021 ◽  
Author(s):  
Bin Yang ◽  
Lin Wang ◽  
Meiyun Zhang ◽  
Weiwei Li ◽  
Qiankun Zhou ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
High Performance ◽  
Recent Progress ◽  
State Of The Art ◽  
Lithium Ion ◽  
Building Blocks ◽  
The State ◽  
Recent Application

The recent application progress and challenges of the state-of-the-art ANF-based membranes for LIB separators are critically reviewed, demonstrating that ANF separators are promising building blocks for high-performance LIB separators.

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