A genetic algorithm for computing the k-error linear complexity of cryptographic sequences

Some cryptographical applications use pseudorandom sequences and require that the sequences are secure in the sense that they cannot be recovered by only knowing a small amount of consecutive terms. Such sequences should therefore have a large linear complexity and also a large k-error linear complexity. Efficient algorithms for computing the kerror linear complexity of a sequence over a finite field only exist for sequences of period equal to a power of the characteristic of the field. It is therefore useful to find a general and efficient algorithm to compute a good approximation of the k-error linear complexity. In this paper we investigate the design of a genetic algorithm to approximate the k-error linear complexity of a sequence. Our preliminary experiments show that the genetic algorithm approach is suitable to the problem and that a good scheme would use a medium sized population, an elitist type of selection, a special design of the two point random crossover and a standard random mutation. The algorithm outputs an approximative value of the k-error linear complexity which is on average only 19.5% higher than the exact value. This paper intends to be a proof of concept that the genetic algorithm technique is suitable for the problem in hand and future research will further refine the choice of parameters

Modified Berlekamp-Massey algorithm for approximating the k-error linear complexity of binary sequences

Some cryptographical applications use pseudorandom sequences and require that the sequences are secure in the sense that they cannot be recovered by only knowing a small amount of consecutive terms. Such sequences should therefore have a large linear complexity and also a large k-error linear complexity. Efficient algorithms for computing the k-error linear complexity of a sequence only exist for sequences of period equal to a power of the characteristic of the field. It is therefore useful to find a general and efficient algorithm to compute a good approximation of the k-error linear complexity. We show that the Berlekamp-Massey Algorithm, which computes the linear complexity of a sequence, can be adapted to approximate the k-error linear complexity profile for a general sequence over a finite field. While the complexity of this algorithm is still exponential, it is considerably more efficient than the exhaustive search

Transformations of European agricultural sector, market and model under the influence of Common Agricultural Policy (CAP)

The European agricultural sector is, for the last decades, a subject to a quite extensive and important transformations imposed by the new paradigm`s changing of the Common Agricultural Policy (CAP), especially the influences of complex phenomena such as integration and globalization of markets under pressure impose by changes in the global economy. From this perspective, the agriculture is not only a traditional economic sector designed to ensure the food safety and food security, but also a complex one; the agriculture becoming multifunctional in rural communities and diversification of the pluriactivities. In this article are analyzed some of the major transformations of this sector, form the perspective of the European agricultural market and European agricultural model under the CAP`s influence

Transformations of European agricultural sector, market and model under the influence of Common Agricultural Policy (CAP)

The European agricultural sector is, for the last decades, a subject to a quite extensive and important transformations imposed by the new paradigm`s changing of the Common Agricultural Policy (CAP), especially the influences of complex phenomena such as integration and globalization of markets under pressure impose by changes in the global economy. From this perspective, the agriculture is not only a traditional economic sector designed to ensure the food safety and food security, but also a complex one; the agriculture becoming multifunctional in rural communities and diversification of the pluriactivities. In this article are analyzed some of the major transformations of this sector, form the perspective of the European agricultural market and European agricultural model under the CAP`s influence

Escape from Competition: Neighbors Reduce Centaurea Stoebe Performance at Home but not Away

The greater abundance of some exotic plants in their nonnative ranges might be explained in part by biogeographic differences in the strength of competition, but these competitive effects have not been experimentally examined in the field. We compared the effects of neighbors on the growth and reproduction of spotted knapweed (Centaurea stoebe) in Europe, where it is native, and in Montana, where it is invasive. There were strong negative competitive effects of neighboring vegetation on C. stoebe growth and reproduction in Europe. In contrast, identical experiments in Montana resulted in insignificant impacts on C. stoebe. Although the mechanisms that produce this dramatic biogeographic difference in competitive outcome remain unknown, our results indicate that differences in net competitive interactions between ranges may contribute to the striking dominance of C. stoebe in parts of North America

Algorithms for the k-error linear complexity of cryptographic sequences over finite fields

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APPROACHES ON MEASURING SUSTAINABLE DEVELOPMENT IN CONTEMPORARY WORLD – BEYOND CLASSICAL INDICATORS

Measurement of sustainable development in the contemporary world represents a topic of wide approach in the context of transformations which global economic environment has experienced over the last half-century. The necessity of identification of new indicators that provide a more faithful image of economic life has imposed the construction of new indicators for measuring. In this context, the central objective of the paper is to achieve a synthesis of some of these indicators, analysing their evolution in the context of existing economic realities but also highlighting further correlations, limitations and disputes to which they are subjected to lately. Thus in this paper are presented and analyzed, considering the arguments above, a series of indicators such as the ecological footprint, biocapacity, happy planet index or other segnificant indicators. Another objective of the paper is also the identification of possible solutions for the application of these indicators in the foundation for sustainable economic policies in the context of global economic transformation

Appendix A. Sites at which neighbor-removal competition experiments were conducted with Centaurea stoebe as the target.

Sites at which neighbor-removal competition experiments were conducted with Centaurea stoebe as the target

The Importance of Dose Intensity When Administering Cytotoxic Chemotherapy in NSCLC—A Matter as Actual Now as in the Past

Lung cancer, as the leading cause of death in oncology is one of the most challenging diseases nowadays. Even after the implementation of checkpoint inhibitors and targeted therapy as a standard of therapy for metastatic disease, the chemotherapy backbone remains essential in the treatment of these patients. This study aimed to evaluate how administration particularities in chemotherapy and toxicity management can influence the outcome. We conducted a retrospective single-institution study, at Elias University Emergency Hospital, Bucharest, Romania, between 2014 and 2018, in a heterogeneous patient population with metastatic non-small cell lung cancer that received combination chemotherapy. The inclusion criteria for this trial were—histological proof of non-small cell lung cancer (NSCLC), stage IV disease, ECOG (Eastern Cooperative Oncology Group) performance status of a maximum of two, treatment with cytotoxic chemotherapy for at least four courses (patients with fewer courses were excluded). All patients received combination chemotherapy. The main focus was on the effect of dose reduction and treatment delay on overall survival and progression-free survival. A total of 129 patients were enrolled. The response rate in the studied population was 69% and 62.8% had no toxicity greater than grade 2. Chemotherapy regimens used had the following distribution—paclitaxel + carboplatin 41.9%, paclitaxel + carboplatin + bevacizumab 12.4%, pemetrexed + carboplatin 12.4%, gemcitabine + carboplatin 26.4% and other regimens 7%. Mean PFS (Progression Free Survival) was 9.1 months and the mean OS (Overall Survival) was 14 months. OS was not significantly different in the treatment delay group versus the no delay one, p < 0.25 but dose- reduction significantly impacted OS, p < 0.03. Administration particularities, like febrile neutropenia prophylaxis, treatment of chemotherapy-related anemia, respecting the details of chemostability and preparation rules and emesis prophylaxis, were considered reasons for the good outcome. Details regarding cytotoxic chemotherapy administration remain of paramount importance for a good outcome and the benefit for survival they convey is crucial. Sometimes the benefit the patient derives from these details is comparable to the one newer therapies convey