This thesis deals with electronic signature in the area of accounting. It includes characteristic of electronic signature, certification authority and time stamp. This thesis explains these fundamental concepts related to the electronic signature and also shows some practical application of it -- such as electronic invoicing, archiving, and communication with state-administration through data boxes or through electronic registries. In this thesis there is also detaily described and depicted the procedure of making electronic invoices and authentication of the certificate of the electronic signature.

Tampering and Reverse Engineering of a chip to extract the hardware Intellectual Property (IP) core or to inject malicious alterations is a major concern. First, offshore chip manufacturing allows the design secrets of the IP cores to be transparent to the foundry and other entities along the production chain. Second, small malicious modifications to the design may not be detectable after fabrication without anti-tamper mechanisms. Counterfeit Integrated Circuits (ICs) also have become an important security issue in recent years, in which counterfeit ICs that perform incorrectly or sub-par to the expected can lead to catastrophic consequences in safety and/or mission-critical applications, in addition to the tremendous economic toll they incur to the semiconductor industry. Some techniques have been developed in the past to improve the defense against such attacks but they tend to fall prey to the increasing power of the attacker. We present a new way to protect against tampering by a clever obfuscation of the design, which can be unlocked with a specific, dynamic path traversal. Hence, the functional mode of the controller is hidden with the help of obfuscated states, and the functional mode is made operational only on the formation of a specific interlocked Code-Word during state transition. A novel time-stamp is proposed that can provide the date at which the IC was manufactured for counterfeit detection. Furthermore, we propose a second layer of tamper resistance to the time-stamp circuit to make it even more difficult to modify. Results show that methods proposed offer higher levels of security with small area overhead. A side benefit is that any small alteration will be magnified via the obfuscated design proposed in these methods. / Master of Science

Made available in DSpace on 2014-12-17T15:37:21Z (GMT). No. of bitstreams: 1 FlavioFB.pdf: 284121 bytes, checksum: ff963989598b589fdee85c0d64ed36f6 (MD5) Previous issue date: 2007-04-13 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Several studies have shown that there is a circadian modulation of explicit memory. This modulation can occur independently in each one of the mnemonic processes. The aim of this study was to evaluate the influence of time of training on short-term memory (STM) and long-term memory (LTM), using a recognition task. Moreover, a possible circadian modulation in retrieving was investigated when this process matched the acquisition hour (time stamp). The chronotype variable was also considered. Fifty-seven undergraduate students aging between 18 and 25 years (21,72 ? 2,14; 28 ♂) participated in this study. In the training phase (acquisition) the subjects heard a ten word list. Following this, they answered a recognition test to evaluate STM and one week later they answered a recognition test to evaluate LTM. In each chronotype, the subjects were divided in groups according to the training hour, part of them in the morning and the other in the afternoon. One week later some of the subjects in each group underwent LTM testing in the morning and others in the afternoon. When the subjects performances were analyzed together, independently of the chronotypes, a training hour effect was found in the LTM. The subjects trained in the afternoon had better performance. No time of day effect was found in the STM and in retrieving from the LTM. However, the morning types who were trained and tested in the same hour had a better performance in the LTM when compared to morning types trained and tested in different hours. This effect did not occur when the other chronotypes were analyzed. The circadian modulation seems to occur at least in two different ways. First, there is a circadian modulation in the acquisition/consolidation processes, with a better performance occuring in the afternoon. Secondly, there is a modulation in the retrieval mnemonic process, called time stamp phenomenon. This phenomenon, that occurred in the morning types, is showed for the first time in humans / Na literatura h? diversas evid?ncias da modula??o circadiana na mem?ria expl?cita. Essa modula??o pode acontecer de forma independente em cada um dos processos mnem?nicos. O objetivo deste trabalho foi avaliar o efeito do hor?rio do dia sobre o desempenho da mem?ria de curto-prazo (MCP) e de longo-prazo (MLP), utilizando testes de reconhecimento de palavras. Al?m disso, foi investigada uma poss?vel modula??o na evoca??o quando esta ocorria no mesmo hor?rio da aquisi??o (estampa temporal), levando em considera??o a vari?vel cronotipo. Participaram do estudo 57 estudantes universit?rios, sendo 28 homens, entre 18 e 25 anos (21,72 ? 2,14). No treino (aquisi??o), os sujeitos escutaram uma lista de dez palavras. Logo a seguir, realizaram um teste de reconhecimento para avaliar a MCP e uma semana depois, realizaram um teste de reconhecimento para avaliar a MLP. Em cada um dos cronotipos, os sujeitos foram divididos em grupos conforme o hor?rio de realiza??o do treino da tarefa, parte pela manh? e a outra parte pela tarde. Uma semana depois parte dos sujeitos em cada um dos grupos realizou o teste para MLP pela manh? e outra pela tarde. Quando o desempenho dos sujeitos foi analisado conjuntamente, independente da classifica??o do cronotipo, foi encontrado um efeito do hor?rio da aprendizagem na MLP, tendo melhor desempenho os sujeito que foram treinados pela tarde. N?o foi evidenciado um efeito do hor?rio na MCP e na evoca??o da MLP. No entanto, os matutinos que foram treinados e testados no mesmo hor?rio tiveram um melhor desempenho do que os matutinos que foram treinados e testados em hor?rio diferentes. Esse fen?meno n?o foi encontrado nos outros cronotipos. A modula??o circadiana na mem?ria de reconhecimento parece ocorrer de pelo menos duas formas distintas. A primeira, no hor?rio da aquisi??o/consolida??o, tendo o hor?rio da tarde uma superioridade em rela??o ao da manh?. E a outra de acordo com o hor?rio em que ocorre a evoca??o (estampa temporal), tendo sido pela primeira vez demonstrado esse fen?meno em seres humanos, ainda que apenas nos matutinos

Short range wireless data communication networks that are used for sport and health care are sometimes called Wireless Body Area Networks (WBANs) and they are located more or less on a person. Sole Integrated Gait Sensor (SIGS) is a research project in WBAN, where wireless pressure sensors are placed like soles in the shoes of persons with different kinds of deceases. The sensors can measure the pressure of the foot relative to the shoe i.e. the load of the two legs is measured. This information can be useful e.g. to not over or under load a leg after joint replacement or as a bio feedback system to help e.g. post stroke patients to avoid falling. The SIGS uses the ANT Protocol and radio specification. ANT uses the 2.4 GHz ISM band and TDMA is used to share a single frequency. The scheduling of time slots is adaptive isochronous co-existence i.e. the scheduling is not static and each transmitter sends periodically but checks for interference with other traffic on the radio channel. In this unidirectional system sole sensors are masters (transmitters) and the WBAN server is the slave in ANT sense. The message rate is chosen as 8 Hz which is suitable for low power consumption. Hence in the SIGS system, it is necessary to synchronize the left and the right foot sensors because of low message rate. In our thesis, we found a method and developed a prototype to receive the time synchronized data in WBAN server from ANT wireless sensor nodes in SIGS system. For this thesis work, a hardware prototype design was developed. The USB and USART communication protocols were also implemented in the hardware prototype. The suitable method for time synchronization was implemented on the hardware prototype. The implemented method receives the sensor data, checks for the correct stream of data; add timestamp to the sensor data and transmit the data to the Linux WBAN server. The time slots allocation in the ANT protocol was found. Alternative solution for the time synchronization in ANT protocol was also provided. The whole SIGS system was tested for its full functionality. The experiments and analysis which we performed were successful and the results obtained provided good time synchronization protocol for ANT low power wireless sensor network and for Wireless Bio-feedback system.

The aim of the presented work is to demonstrate and evaluate the contribution of computing system SIMD especially units MMX, SSE, SSE2, SSE3, SSSE3 and SSE4 from Intel company, by creation of demostrating applications with using Intel Integrated Performance Primitives library. At first, possibilities of SIMD programming using intrinsic function, vektorization and libraries Intel Integrated Performance Primitives are presented, as next are descibed options of evaluation of particular algorithms. Finally procedure of programing by using Intel Integrated Performance Primitives library are ilustrated.

The goal of the thesis is to analyse the issue of e-government in the Czech republic and its impact on private sector. It both describes the current situation and searches for new opportunities to enhance and modify the system. Based on the performed analyses the thesis designs a suitable way to benefit from e-goverment utilization within the company.

Diploma thesis is focused on matters of electronic signatures and their possible usage in accounting and business process. The paper is divided into two parts. Subject of the first part is general analysis of terminology and characteristics of electronic signature, certificates and certification authorities and time stamps, including analysis of strengths and weaknesses of these services. At the end of this theory part are outlined some of the most common choices of using electronic signature in accounting system. In second part are analysed results of research, which was performed by sending questionnaire to a number of randomly chosen companies.

Electronic Legal Transaction: Comparative analysis with emphasis on the use of electronic signature under the EU law and laws of the Czech Republic and Germany Abstract (English) Objectives. This thesis provides a comparative analysis of electronic legal transactions under the EU law and laws of the Czech Republic and Germany, while emphasising the utilisation of higher versions of electronic signature, especially of a qualified electronic signature, which has legal effects of a handwritten signature in legal transactions performed by electronic means (Chapters 6 to 10). At the same time, increased attention is also paid to entirely novel concepts of advanced and qualified electronic seal, which are intended exclusively for use by juristic persons. The laws under scrutiny are based especially on recently adopted Regulation (EU) No 910/2014, known as eIDAS. To provide a general background, the comparative analysis is preceded by a theoretical part (Chapters 2 to 4, partially Chapter 5), dealing with the concept of legal transactions (also termed "legal acts" or "legal action") in general, while also focusing on the traditional handwritten signature and its functions, especially in view of the German and Czech legal doctrines and with occasional references to common law, as well as to requirements ensuing...

Electronic Legal Transaction: Comparative analysis with emphasis on the use of electronic signature under the EU law and laws of the Czech Republic and Germany Abstract (English) Objectives. This thesis provides a comparative analysis of electronic legal transactions under the EU law and laws of the Czech Republic and Germany, while emphasising the utilisation of higher versions of electronic signature, especially of a qualified electronic signature, which has legal effects of a handwritten signature in legal transactions performed by electronic means (Chapters 6 to 10). At the same time, increased attention is also paid to entirely novel concepts of advanced and qualified electronic seal, which are intended exclusively for use by juristic persons. The laws under scrutiny are based especially on recently adopted Regulation (EU) No 910/2014, known as eIDAS. To provide a general background, the comparative analysis is preceded by a theoretical part (Chapters 2 to 4, partially Chapter 5), dealing with the concept of legal transactions (also termed "legal acts" or "legal action") in general, while also focusing on the traditional handwritten signature and its functions, especially in view of the German and Czech legal doctrines and with occasional references to common law, as well as to requirements ensuing...