6,307 research outputs found

    Triplicity of Quarks and Leptons

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    Quarks come in three colors and have electric charges in multiples of one-third. There are also three families of quarks and leptons. Whereas the first two properties can be understood in terms of unification symmetries such as SU(5), SO(10), or E_6, why there should only be three families remains a mystery. I propose how all three properties involving the number three are connected in a fivefold application of the gauge symmetry SU(3).Comment: 10 pages, including 2 figure

    External Auditor Dealing With Deep Cyber Security of Open Networks

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    We focus on how you can release major updates to that customer as much as possible, and we suggest a new model called Cloud Storage Audit with verifiable outsourcing for major updates. Within this model, major updates can be outsourced safely to authorized parties, so the important thing throughout the customer is that downloading the update is being saved very little. Moreover, the design gives us the ability to verify the validity of the encrypted secret keys issued by the OA. Specifically, we employ external auditors in current general audit designs; allow it to act as a delegated party in our position, and is also responsible for secure audits and major key updates to resist key detection. When the cloud downloads new files, the client should download the encrypted password only in OA. The licensed party maintains the encrypted secret key from the client for cloud storage audit and updates the encrypted status every time. The client downloads the encrypted password to the authorized authority and encrypts it exactly as it would like to upload new files to the cloud. In our design, only the agriculture authority should keep the encrypted form of the customer's secret key. In our design, only the agriculture authority should keep the encrypted form of the customer's secret key. We formalize the meaning and type of security in this form

    B-L Violating Nucleon Decay and GUT Scale Baryogenesis in SO(10)

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    We show that grand unified theories based on SO(10) generate naturally the next-to-leading baryon number violating operators of dimension seven. These operators, which violate B-L, lead to unconventional decays of the nucleon such as n -> e^-K^+, e^- \pi^+ and p -> \nu \pi^+. In two-step breaking schemes of non-supersymmetric SO(10), nucleon lifetime for decays into these modes is found to be within reach of experiments. We also identify supersymmetric scenarios where these decays may be accessible, consistent with gauge coupling unification. Further, we show that the (B-L)-asymmetry generated in the decays of GUT scale scalar bosons and/or gauge bosons can explain consistently the observed baryon asymmetry of the universe. The induced (B-L)-asymmetry is sphaleron-proof, and survives down to the weak scale without being erased by the electroweak interactions. This mechanism works efficiently in a large class of non-SUSY and SUSY SO(10) models, with either a 126 or a 16 Higgs field employed for rank reduction. In minimal models the induced baryon asymmetry is tightly connected to the masses of quarks, leptons and neutrinos and is found to be compatible with observations.Comment: 26 pages, 9 figure

    Characterization 410 Stainless Steel by Vacuum Tempering Process

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    It has been reported that low-temperature vacuum tempering of 410 stainless steel hard layer improving wear resistance and hardness. Grade 410 stainless steel being a hardened material were modified by low temperature tempering process. By the process of tempering, brittleness on the stainless steel material will be reduced and ductility will be promoted. The microstructure, surface hardness and erosion-corrosion resistance were systematically evaluated. Vacuum tempering is done at low temperature of 430℃ can form a hardened layer, and with the treated time prolong, the thickness of the layer increased. The stainless specimens were vacuum tempered for 30 minutes, 60 minutes and 120 minutes. Wear tests were conducted with the help of pin on disc apparatus. The output results were determined with various metallographic tests like scanning electron microscope and optical microscope results

    Vanishing magnetic mass in QED3_{3} with a Chern-Simons term

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    We show that, at one loop, the magnetic mass vanishes at finite temperature in QED in any dimension. In QED3_{3}, even the zero temperature part can be regularized to zero. We calculate the two loop contributions to the magnetic mass in QED3_{3} with a Chern-Simons term and show that it vanishes. We give a simple proof which shows that the magnetic mass vanishes to all orders at finite temperature in this theory. This proof also holds for QED in any dimension.Comment: revtex, 7 pages, 5 figure

    The Control of Myocardial Contraction with Skeletal Fast Muscle Troponin C.

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    The present study describes experiments on the myocardial trabeculae from the right ventricle of Syrian hamsters whose troponin C (TnC) moiety was exchanged with heterologous TnC from fast skeletal muscle of the rabbit. These experiments were designed to help define the role of the various classes of Ca2+-binding sites on TnC in setting the characteristic sensitivities for activations of cardiac and skeletal muscles. Thin trabeculae were skinned and about 75% of their troponin C extracted by chemical treatment. Tension development on activations by Ca2+ and Sr2+ was found to be nearly fully blocked in such TnC extracted preparations. Troponin C contents and the ability to develop tension on activations by Ca2+ and Sr2+ was permanently restored after incubation with 2-6 mg/ml purified TnC from either rabbit fast-twitch skeletal muscle (STnC) or the heart (CTnC, cardiac troponin C). The native (skinned) cardiac muscle is characteristically about 5 times more sensitive to activation by Sr2+ than fast muscle, but the STnC-loaded trabeculae gave response like fast muscle. Attempts were also made to exchange the TnC in psoas (fast-twitch muscle) fibers, but unlike cardiac muscle tension response of the maximally extracted psoas fibers could be restored only with homologous STnC. CTnC was effective in partially extracted fibers, even though the uptake of CTnC was complete in the maximally extracted fibers. The results in this study establish that troponin C subunit is the key in setting the characteristic sensitivity for tension control in the myocardium above that in the skeletal muscle. Since a major difference between skeletal and cardiac TnCs is that one of the trigger sites (site I, residues 28-40 from the N terminus) is modified in CTnC and has reduced affinity for Ca2+ binding, the possibility is raised that this site has a modulatory effect on activation in different tissues and limits the effectiveness of CTnC in skeletal fibers

    Effective Lagrangian Approach to the Fermion Mass Problem

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    An effective theory is proposed, combining the standard gauge group SU(3)CSU(2)LU(1)YSU(3)_{C}\otimes SU(2)_{L}\otimes U(1)_{Y} with a horizontal discrete symmetry. By assigning appropriate charges under this discrete symmetry to the various fermion fields and to (at least) two Higgs doublets, the broad spread of the fermion mass and mixing angle spectrum can be explained as a result of suppressed, non-renormalisable terms. A particular model is constructed which achieves the above while simultaneously suppressing neutral Higgs-induced flavour-changing processes.Comment: 21 pages, UM-P-93/81, latex file, 1 figure available on reques

    The Stability of the Gauge Hierarchy in SU(5)×SU(5)SU(5) \times SU(5)

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    It has been shown that the Dimopoulos-Wilczek (or missing-VEV) mechanism for doublet-triplet splitting can be implemented in SU(5)×SU(5)SU(5) \times SU(5) models, which requires no adjoint Higgs fields. This is an advantage from the point of view of string theory construction. Here the stability of the gauge hierarchy is examined in detail, and it is shown that it can be guaranteed much more simply than in SO(10)SO(10). In fact a Z2Z_2 symmetry ensures the stability of the DW form of the expectation values to all orders in GUT-scale VEVs. It is also shown that models based on SO(10)×SU(5)SO(10) \times SU(5) have the advantages of SU(5)×SU(5)SU(5) \times SU(5) while permitting complete quark-lepton unification as in SO(10)SO(10).Comment: 13 pages, LaTe

    Constraints on radiative decay of the 17-keV neutrino from COBE Measurements

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    It is shown that, for a nontrivial radiative decay channel of the 17-keV neutrino, the photons would distort the microwave background radiation through ionization of the universe. The constraint on the branching ratio of such decays from COBE measurements is found to be more stringent than that from other considerations. The limit on the branching ratio in terms of the Compton yy parameter is Bγ<1.5×107(τν1011sec)0.45(y103)1.11h1B_\gamma < 1.5 \times 10^{-7} ({\tau_\nu \over 10^{11} sec})^{0.45} ({y \over 10^{-3}})^{1.11} h^{-1} for an Ω=1,Ωb=0.1\Omega=1, \Omega_b=0.1 universe.Comment: 7 pages. (figures will be sent on request) (To appear in Phys. Rev. D.

    An Empirical Critique of On-Demand Routing Protocols against Rushing Attack in MANET

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    Over the last decade, researchers had  proposed numerous  mobile ad hoc routing protocols for which are operate in an on-demand way, as standard on-demand routing protocols such as AODV, DSR and TORA, etc., have been shown to often have faster reaction time and  lower overhead than proactive protocols. However, the openness of the routing environment and the absence of centralized system and infrastructure make them exposed to security attacks in large extent.  In particular, one such kind of attacks is rushing attack, which is mostly hard to detect due to their inherited properties, that alters the network statistics radically. In this paper, we modeled a rushing attack which is a powerful attack that exploits the weaknesses of the secure routing protocols. Moreover, to know the weakness and strength of these protocols, it is necessary to test their performance in hostile environments. Subsequently, the performance is measured with the various metrics, some ot them are average throughput, packet delivery ratio, average end-to-end delay and etc., to compare and evaluate their performance
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