O perfil de excitação Raman do anion esquarato, C 4 O 4 -2 , foi calculado por métodos ab initio no nível de teoria Hartree-Fock utilizando a Teoria de Resposta Linear (TRL) para seis frequências de excitação: 632,5, 514,5, 488,0, 457,9, 363,8 e 337,1 nm. Um total de cinco conjuntos de funções de base (6-31G*, 6-31+G*, cc-pVDZ, aug-cc-pVDZ e bases de Sadlej) foi investigado visando comparar o d...

Nowadays, users can easily access and download network attack tools, which often provide friendly interfaces and easily operated features, from the Internet. Therefore, even a naive hacker can also launch a large scale DoS or DDoS attack to prevent a system, i.e., the victim, from providing Internet services. In this paper, we propose an agent based intrusion detection architecture, which is a ...

Denial of service (DoS) attacks figure highly among the dangers that face the Internet. Many research studies deal with DoS, proposing models and/or architectures to stop this threat. The proposed solutions vary between prevention, detection, filtering and traceback of the attack. The latter (attack traceback) constitutes an important part of the DoS defense. The most complex issue it has to fa...

Este artigo investiga o surgimento e o papel dos gestores de rede, um segmento de empresas recentemente constituído, mas que tem se revelado importante para a estruturação do canal de correspondentes bancários (CBs). A partir de um desenho de pesquisa qualitativo e de entrevistas com executivos de bancos e empresas gestoras de rede, o artigo apresenta: (i) o histórico deste segmento, e (ii) os ...

A wireless network is more vulnerable to denial of service (DoS) attacks than a wired one. In this paper we propose a new DoS defense scheme toward actively resisting DoS attacks. A mobile terminal generates an authorized anonymous ID (AAI) using its true ID, and assigns its true ID with the produced AAI. Using an AAI, a legitimate mobile terminal will be authenticated by the wireless network, ...

Frutos de Sapindus saponaria (Sapindaceae), uma planta amplamente distribuída nos trópicos, foram coletados a cada trinta dias, durante seis meses. Estudos usando cromatografia a líquido com detecção por UV e EM (CLAE/UV/ESI-EM) e fragmentações por EM/EM, mostraram que os principais glicosídeos presentes nesses frutos são saponinas (SAP) derivadas dos triterpenos hederagenina e ácido oleanólico...

In today’s networks one major problem, especially for Service Providers, is related to various attacks either active or passive. Denial of Services (DoS) is one of the most difficult to detect and stop. Denial of Service (DoS) and its derivative, Distributed Denial of Service (DDoS) are some of the most common attacks. There are many types of DoS: Buffer Overflow, SYN attacks, teardrop attack, ...

The phonon density of states of elemental Au, Cu, and Cu3Au with L12 chemical order were measured by inelastic neutron scattering and used to calculate the vibrational entropy of formation of the ordered compound from the elemental metals. A vibrational entropy of formation of (0.0660.03) kB /atom at 300 K was obtained, with the vibrational entropy of the ordered alloy being larger than that of...

The research community has established that WiMAX networks suffer from Denial of Service (DoS) vulnerabilities. In this paper, we analyze how WiMAX system parameter settings increase or decrease DoS vulnerabilities of WiMAX networks. The behavior of the WiMAX MAC level protocol is sensitive to the settings of core system parameters. Unlike traditional network-based DoS attacks, attacks resultin...

Me tá te se é uma re a ção atra en te para a con ver são de óle os e gor du ras em pro du tos quí mi cos úte is. Assim, a me tá te se de és te res de áci dos gra xos in sa tu ra dos (cons ti tu in tes bá si cos de óle os e gor du ras) é uma rota con ve ni en te para a sín te se de diés te res in sa tu ra dos, que po dem ser usa dos como in ter me diá ri os na pro du ção de po lí me ros e na quí...