923 resultados para Algebraic attacks


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Abstract The storage susceptibility of Bambara groundnut (B. G.) (Voandzeia Subterranean (L.) Thouars) to Callosobruchus maculatus and chemical and functional properties of 11 varieties form Far-North of Cameroon were investigate using standard analytical methods. Storage susceptibility shown that, after five months within treatment, C. maculatus destroy 10 to 50% of grains. The chemical characteristics of none attack grains of 11 varieties were range to 18.64 at 21.08%, 6.85 at 7.44%, 49.75 at 52.68% and to 6.05 at 7.55% respectively for protein, fat, starch and free carbohydrate. These chemical characteristics significantly (p < 0.05) decreases form attacks varieties. For the functional parameters, the none attacks grains was range of 130 at 135%, 19.15 at 20.91%, 18.20 at 21.13%, 2.76 at 3.21% and of 8.54 at 10.14% respectively for water capacity absorption, solubility index, gel length, ash and humidity. The results of this study indicated that storage susceptibility, chemical and functional properties of B. G. be dependant to the varieties.

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X-ray computed log tomography has always been applied for qualitative reconstructions. In most cases, a series of consecutive slices of the timber are scanned to estimate the 3D image reconstruction of the entire log. However, the unexpected movement of the timber under study influences the quality of image reconstruction since the position and orientation of some scanned slices can be incorrectly estimated. In addition, the reconstruction time remains a significant challenge for practical applications. The present study investigates the possibility to employ modern physics engines for the problem of estimating the position of a moving rigid body and its scanned slices which are subject to X-ray computed tomography. The current work includes implementations of the extended Kalman filter and an algebraic reconstruction method for fan-bean computer tomography. In addition, modern techniques such as NVidia PhysX and CUDA are used in current study. As the result, it is numerically shown that it is possible to apply the extended Kalman filter together with a real-time physics engine, known as PhysX, in order to determine the position of a moving object. It is shown that the position of the rigid body can be determined based only on reconstructions of its slices. However, the simulation of the body movement sometimes is subject to an error during Kalman filter employment as PhysX is not always able to continue simulating the movement properly because of incorrect state estimation.

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Leveraging cloud services, companies and organizations can significantly improve their efficiency, as well as building novel business opportunities. Cloud computing offers various advantages to companies while having some risks for them too. Advantages offered by service providers are mostly about efficiency and reliability while risks of cloud computing are mostly about security problems. Problems with security of the cloud still demand significant attention in order to tackle the potential problems. Security problems in the cloud as security problems in any area of computing, can not be fully tackled. However creating novel and new solutions can be used by service providers to mitigate the potential threats to a large extent. Looking at the security problem from a very high perspective, there are two focus directions. Security problems that threaten service user’s security and privacy are at one side. On the other hand, security problems that threaten service provider’s security and privacy are on the other side. Both kinds of threats should mostly be detected and mitigated by service providers. Looking a bit closer to the problem, mitigating security problems that target providers can protect both service provider and the user. However, the focus of research community mostly is to provide solutions to protect cloud users. A significant research effort has been put in protecting cloud tenants against external attacks. However, attacks that are originated from elastic, on-demand and legitimate cloud resources should still be considered seriously. The cloud-based botnet or botcloud is one of the prevalent cases of cloud resource misuses. Unfortunately, some of the cloud’s essential characteristics enable criminals to form reliable and low cost botclouds in a short time. In this paper, we present a system that helps to detect distributed infected Virtual Machines (VMs) acting as elements of botclouds. Based on a set of botnet related system level symptoms, our system groups VMs. Grouping VMs helps to separate infected VMs from others and narrows down the target group under inspection. Our system takes advantages of Virtual Machine Introspection (VMI) and data mining techniques.

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IoT consists of essentially thousands of tiny sensor nodes interconnected to the internet, each one of which executes the programmed functions under memory and power limita- tions. The sensor nodes are distributed mainly for gathering data in various situations. IoT envisions the future technologies such as e-health, smart city, auto-mobiles automa- tion, construction sites automation, and smart home. Secure communication of data under memory and energy constraints is major challenge in IoT. Authentication is the first and important phase of secure communication. This study presents a protocol to authenticate resource constraint devices in physical proximity by solely using the shared wireless communication interfaces. This model of authentication only relies on the abundance of ambient radio signals to authenticate in less than a second. To evaluate the designed protocol, SkyMotes are emulated in a network environment simulated by Contiki/COOJA. Results presented during this study proves that this approach is immune against passive and active attacks. An adversary located as near as two meters can be identified in less than a second with minimal expense of energy. Since, only radio device is used as required hardware for the authentication, this technique is scalable and interoperable to heterogeneous nature of IoT.

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Optimization of quantum measurement processes has a pivotal role in carrying out better, more accurate or less disrupting, measurements and experiments on a quantum system. Especially, convex optimization, i.e., identifying the extreme points of the convex sets and subsets of quantum measuring devices plays an important part in quantum optimization since the typical figures of merit for measuring processes are affine functionals. In this thesis, we discuss results determining the extreme quantum devices and their relevance, e.g., in quantum-compatibility-related questions. Especially, we see that a compatible device pair where one device is extreme can be joined into a single apparatus essentially in a unique way. Moreover, we show that the question whether a pair of quantum observables can be measured jointly can often be formulated in a weaker form when some of the observables involved are extreme. Another major line of research treated in this thesis deals with convex analysis of special restricted quantum device sets, covariance structures or, in particular, generalized imprimitivity systems. Some results on the structure ofcovariant observables and instruments are listed as well as results identifying the extreme points of covariance structures in quantum theory. As a special case study, not published anywhere before, we study the structure of Euclidean-covariant localization observables for spin-0-particles. We also discuss the general form of Weyl-covariant phase-space instruments. Finally, certain optimality measures originating from convex geometry are introduced for quantum devices, namely, boundariness measuring how ‘close’ to the algebraic boundary of the device set a quantum apparatus is and the robustness of incompatibility quantifying the level of incompatibility for a quantum device pair by measuring the highest amount of noise the pair tolerates without becoming compatible. Boundariness is further associated to minimum-error discrimination of quantum devices, and robustness of incompatibility is shown to behave monotonically under certain compatibility-non-decreasing operations. Moreover, the value of robustness of incompatibility is given for a few special device pairs.

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Mobile malwares are increasing with the growing number of Mobile users. Mobile malwares can perform several operations which lead to cybersecurity threats such as, stealing financial or personal information, installing malicious applications, sending premium SMS, creating backdoors, keylogging and crypto-ransomware attacks. Knowing the fact that there are many illegitimate Applications available on the App stores, most of the mobile users remain careless about the security of their Mobile devices and become the potential victim of these threats. Previous studies have shown that not every antivirus is capable of detecting all the threats; due to the fact that Mobile malwares use advance techniques to avoid detection. A Network-based IDS at the operator side will bring an extra layer of security to the subscribers and can detect many advanced threats by analyzing their traffic patterns. Machine Learning(ML) will provide the ability to these systems to detect unknown threats for which signatures are not yet known. This research is focused on the evaluation of Machine Learning classifiers in Network-based Intrusion detection systems for Mobile Networks. In this study, different techniques of Network-based intrusion detection with their advantages, disadvantages and state of the art in Hybrid solutions are discussed. Finally, a ML based NIDS is proposed which will work as a subsystem, to Network-based IDS deployed by Mobile Operators, that can help in detecting unknown threats and reducing false positives. In this research, several ML classifiers were implemented and evaluated. This study is focused on Android-based malwares, as Android is the most popular OS among users, hence most targeted by cyber criminals. Supervised ML algorithms based classifiers were built using the dataset which contained the labeled instances of relevant features. These features were extracted from the traffic generated by samples of several malware families and benign applications. These classifiers were able to detect malicious traffic patterns with the TPR upto 99.6% during Cross-validation test. Also, several experiments were conducted to detect unknown malware traffic and to detect false positives. These classifiers were able to detect unknown threats with the Accuracy of 97.5%. These classifiers could be integrated with current NIDS', which use signatures, statistical or knowledge-based techniques to detect malicious traffic. Technique to integrate the output from ML classifier with traditional NIDS is discussed and proposed for future work.

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Karl Popper versus Theodor Adorno: Lessons from a historical confrontation. In 1961, during the Congress of the German Society of Sociology, two great theoretical references of the XX century faced in a historical debate about the logic of the social sciences. In addition to methodological issues strict sense, the confrontation became known as a debate between positivism and dialectic. The article first deals with the theoretical trajectories of Popper and Adorno and the relation of their theories with their political and ideological certainties. On one hand, the trajectory of the Popperian epistemology is examined, its contributions and vigorous attacks on Marx in what he called 'poverty of historicism" and false predictive Marxist world, and, on the other hand, the role of Adorno in the Frankfurt School, his criticism of totalitarianism and the defense of a critical emancipatory reason. The article also deals with the confrontation itself, the exposure of Popper's twenty-seven theses that culminate with the situation logic and the method of the economy as exemplary for the social sciences and Adorno's critical perspective of sociology and society as non-separable objects. In conclusion we show how the articulation of theory with the weltanschauung of each author helps to clarify the terms of the debate and how the confrontation contributed unequivocally to the dynamics of scientific progress and for the critical history of the ideas.

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Internetin yhteisöpalveluiden käyttäjien avoimuus ja sosiaalisuus altistavat heidät monenlaisille riskeille. “Social engineering” eli käyttäjien manipulointi on uhka, joka liittyy informaation hankkimiseen perinteisen kanssakäymisen kautta, mutta yhä enenevissä määrin myös internetissä. Kun kanssakäyminen tapahtuu internetin välityksellä, käyttäjien manipuloijat hyödyntävät yhteisöpalveluita yhteydenpitoon uhrien kanssa sekä paljon käyttäjäinformaatiota sisältävänä alustana. Tämän tutkielman tarkoitus on löytää internetin yhteisöpalveluiden ja käyttäjien manipuloinnin välinen yhteys. Tämä päämäärä saavutettiin etsimällä vastauksia kysymyksiin kuten: Mitkä ovat tyypilliset hyökkäystyypit? Miksi informaatiolla on niin suuri rooli? Mitä seurauksia ilmiöllä on ja miten hyökkäyksiltä on mahdollista suojautua? Vastaukset kysymyksiin löydettiin toteuttamalla systemaattinen kirjallisuuskatsaus. Katsaus muodostui yhdistämällä tärkeimmät löydökset 60 tarkoin valitusta ilmiötä käsittelevästä artikkelista. Käyttäjien manipuloinnin huomattiin olevan hyvin laaja ja monimutkainen ilmiö internetin yhteisöpalveluissa. Huomattiin, että manipulointia ilmenee sivustoilla useissa erilaisissa muodoissa, joita ovat muun muassa tietojen kalastelu, profiilien yhdistäminen, sosiaaliset sovellukset, roskaposti, haitalliset linkit, identiteettivarkaudet, tietovuodot ja erilaiset huijaukset, jotka hyödyntävät sekä ihmisluonnon että sivustojen perusominaisuuksia. Haavoittuvuus ja luottamus havaittiin myös tärkeiksi aspekteiksi, sillä ne yhdistävät informaation merkityksen ja ihmisluonnon, jotka molemmat ovat avaintekijöitä sekä manipuloinnissa että yhteisöpalvelusivustoilla. Vaikka ilmiön seurausten huomattiin olevan negatiivisia niin käyttäjien olemukselle internetissä kuin todellisessakin elämässä, havaittiin myös, että ilmiön ymmärtäminen ja tunnistaminen helpottaa siltä suojautumista

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Modern automobiles are no longer just mechanical tools. The electronics and computing services they are shipping with are making them not less than a computer. They are massive kinetic devices with sophisticated computing power. Most of the modern vehicles are made with the added connectivity in mind which may be vulnerable to outside attack. Researchers have shown that it is possible to infiltrate into a vehicle’s internal system remotely and control the physical entities such as steering and brakes. It is quite possible to experience such attacks on a moving vehicle and unable to use the controls. These massive connected computers can be life threatening as they are related to everyday lifestyle. First part of this research studied the attack surfaces in the automotive cybersecurity domain. It also illustrated the attack methods and capabilities of the damages. Online survey has been deployed as data collection tool to learn about the consumers’ usage of such vulnerable automotive services. The second part of the research portrayed the consumers’ privacy in automotive world. It has been found that almost hundred percent of modern vehicles has the capabilities to send vehicle diagnostic data as well as user generated data to their manufacturers, and almost thirty five percent automotive companies are collecting them already. Internet privacy has been studies before in many related domain but no privacy scale were matched for automotive consumers. It created the research gap and motivation for this thesis. A study has been performed to use well established consumers privacy scale – IUIPC to match with the automotive consumers’ privacy situation. Hypotheses were developed based on the IUIPC model for internet consumers’ privacy and they were studied by the finding from the data collection methods. Based on the key findings of the research, all the hypotheses were accepted and hence it is found that automotive consumers’ privacy did follow the IUIPC model under certain conditions. It is also found that a majority of automotive consumers use the services and devices that are vulnerable and prone to cyber-attacks. It is also established that there is a market for automotive cybersecurity services and consumers are willing to pay certain fees to avail that.

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Increased losses of eggs and chicks resulting from human intrusion (investigator or other) into seabird colonies has been well documented. In 1990/91, I studied the effects of investigator disturbance on aggressive behaviour and breeding success of individual pairs of ring-billed gulls nesting at two colonies near Port Colborne, Ontario. The insular colony was on an artificial breakwall, associated with the Welland Ship Canal, approximately 1 km off the north shore of Lake Erie. The mainland colony was adjacent to the canal approximately 1 km east of the breakwall. The frequencies of adult threat and assault behaviours, chick movement and adult attacks on chicks were recorded by continuous scan sampling 30 min prior to, 30 min during and 60 (2 X 30) min after investigator disturbance. The frequency of threat and assault behaviours increased during the period of investigator activity in the colony while the duration of wingpulls and beakpulls decreased. Significantly more chicks ran ("runners") from their natal territories during disturbances and "runners" were more frequently attacked than "territorial" chicks. No chicks were fatally attacked during disturbance and "runners" returned to their natal territories quickly after disturbance. Breeding success was determined for pairs nesting in study plots subjected to two levels of disturbance (normal and moderate). The disturbance level of each plot differed in visitation frequency and activities performed on each visit. Investigator disturbance had no effect on the hatching success or fledging success (taken as 21 days of age) of ring-billed gull study pairs at either colony.

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The algebraic expressions for the anharmonic contributions to the Debye-Waller factor up to 0(A ) and 0 L% ) £ where ^ is the scattering wave-vector] have been derived in a form suitable for cubic metals with small ion cores where the interatomic potential extends to many neighbours. This has been achieved in terms of various wave-vector dependent tensors, following the work of Shukla and Taylor (1974) on the cubic anharmonic Helmholtz free energy. The contribution to the various wave-vector dependent tensors from the coulomb and the electron-ion terms in the interatomic metallic potential has been obtained by the Ewald procedure. All the restricted multiple whole B r i l l o u i n zone (B.Z.) sums are reduced to single whole B.Z. sums by using the plane wave representation of the delta function. These single whole B.Z. sums are further reduced to the •%?? portion of the B.Z. following Shukla and Wilk (1974) and Shukla and Taylor (1974). Numerical calculations have been performed for sodium where the Born-Mayer term in the interatomic potential has been neglected because i t is small £ Vosko (1964)3 • *n o^er to compare our calculated results with the experimental results of Dawton (1937), we have also calculated the r a t io of the intensities at different temperatures for the lowest five reflections (110), (200), (220), (310) and (400) . Our calculated quasi-harmonic results agree reasonably well with the experimental results at temperatures (T) of the order of the Debye temperature ( 0 ). For T » © ^ 9 our calculated anharmonic results are found to be in good agreement with the experimental results.The anomalous terms in the Debye-Waller factor are found not to be negligible for certain reflections even for T ^ ©^ . At temperature T yy Op 9 where the temperature is of the order of the melting temperature (Xm) » "the anomalous terms are found to be important almost for all the f i ve reflections.

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RelAPS is an interactive system assisting in proving relation-algebraic theorems. The aim of the system is to provide an environment where a user can perform a relation-algebraic proof similar to doing it using pencil and paper. The previous version of RelAPS accepts only Horn-formulas. To extend the system to first order logic, we have defined and implemented a new language based on theory of allegories as well as a new calculus. The language has two different kinds of terms; object terms and relational terms, where object terms are built from object constant symbols and object variables, and relational terms from typed relational constant symbols, typed relational variables, typed operation symbols and the regular operations available in any allegory. The calculus is a mixture of natural deduction and the sequent calculus. It is formulated in a sequent style but with exactly one formula on the right-hand side. We have shown soundness and completeness of this new logic which verifies that the underlying proof system of RelAPS is working correctly.

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This was a weekly paper that was published every Saturday. The motto of the Merrimack was: "Not too rash--Yet not fearful--We aim to be just." It was published from 1808-1817. Topics of interest include: Page 1: State of New York Republicans published a statement arguing against the war and the policies of John Adams and James Madison; account of the capture of York by the Americans, 27 April 1813; Page 2: account of the capture of York by the Americans, 27 April 1813; letter from American Brig. Gen. Henry Miller to Sir John B. Warren warning the British not to execute captured U.S. citizen O'Neal; response from Sir John B. Warren to Brig. Gen. Henry Miller stating that O'Neal had been released; account of Stephen Girard buying back his ransomed ship from the British; Page 3: account of Stephen Girard buying back his ransomed ship from the British; U.S. General Harrison repels British and Indian forces that attack Fort Meigs; account of British forces capturing U.S. privateer ship Alexander; report of British forces near Newport, New York, the Delaware river, and the Potomac River; report of Indian attacks in Kaskaskia, Randolph County; report of a boat load of provisions attacked by Indians near Fort Harrison; Commodore Isaac Chauncey arrived at Sacket's Harbor to unload stores taken from York before leaving for Niagara to commence attack against Fort George; U.S. Army announcement recruiting men 18 to 45 years of age to enlist in the army;

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A weekly paper that was published from 1805 to 1814. War related news includes: Page 103 - Weekly Retrospect: Troop movements of Captain Morgan and a company of light dragoons from Niagara to Greenbush; report on the Battle of Queenston Heights including a casualty listing and a mention of the death of Major General Isaac Brock and Colonel McDonald and the American's respect for Brock; British attach of Fort Erie and the Village of Black Rock; the privateer Globe under Captain Murphy returning to Baltimore after capturing a British letter of marque; First Nation / Indian attacks near St. Louis; movements of General W. Harrison and army from Fort Defiance to the rapids of Miama (Miami). The rest of the newspaper contains literary works (poems and translations), essays (including on celibacy), marriages, deaths and other anecdotes. The motto on the front page states: "Visiting Every Flower with Labour Meet, and Gathering all its Treasures, Sweet by Sweet."

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Chlorhexidine is an effective antiseptic used widely in disinfecting products (hand soap), oral products (mouthwash), and is known to have potential applications in the textile industry. Chlorhexidine has been studied extensively through a biological and biochemical lens, showing evidence that it attacks the semipermeable membrane in bacterial cells. Although extremely lethal to bacterial cells, the present understanding of the exact mode of action of chlorhexidine is incomplete. A biophysical approach has been taken to investigate the potential location of chlorhexidine in the lipid bilayer. Deuterium nuclear magnetic resonance was used to characterize the molecular arrangement of mixed phospholipid/drug formulations. Powder spectra were analyzed using the de-Pake-ing technique, a method capable of extracting both the orientation distribution and the anisotropy distribution functions simultaneously. The results from samples of protonated phospholipids mixed with deuterium-labelled chlorhexidine are compared to those from samples of deuterated phospholipids and protonated chlorhexidine to determine its location in the lipid bilayer. A series of neutron scattering experiments were also conducted to study the biophysical interaction of chlorhexidine with a model phospholipid membrane of DMPC, a common saturated lipid found in bacterial cell membranes. The results found the hexamethylene linker to be located at the depth of the glycerol/phosphate region of the lipid bilayer. As drug concentration was increased in samples, a dramatic decrease in bilayer thickness was observed. Differential scanning calorimetry experiments have revealed a depression of the DMPC bilayer gel-to-lamellar phase transition temperature with an increasing drug concentration. The enthalpy of the transition remained the same for all drug concentrations, indicating a strictly drug/headgroup interaction, thus supporting the proposed location of chlorhexidine. In combination, these results lead to the hypothesis that the drug is folded approximately in half on its hexamethylene linker, with the hydrophobic linker at the depth of the glycerol/phosphate region of the lipid bilayer and the hydrophilic chlorophenyl groups located at the lipid headgroup. This arrangement seems to suggest that the drug molecule acts as a wedge to disrupt the bilayer. In vivo, this should make the cell membrane leaky, which is in agreement with a wide range of bacteriological observations.