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A dubiety-determining based model for database cumulated anomaly intrusion
The concept of Cumulated Anomaly (CA), which describes a new type of database anomalies, is addressed. A
typical CA intrusion is that when a user who is authorized to modify data records under certain constraints deliberately
hides his/her intentions to change data beyond constraints in different operations and different transactions. It happens
when some appearing to be authorized and normal transactions lead to certain accumulated results out of given thresholds.
The existing intrusion techniques are unable to deal with CAs. This paper proposes a detection model,
Dubiety-Determining Model (DDM), for Cumulated Anomaly. This model is mainly based on statistical theories and fuzzy
set theories. It measures the dubiety degree, which is presented by a real number between 0 and 1, for each database
transaction, to show the likelihood of a transaction to be intrusive. The algorithms used in the DDM are introduced. A
DDM-based software architecture has been designed and implemented for monitoring database transactions. The
experimental results show that the DDM method is feasible and effective
Statistical and fuzzy approach for database security
A new type of database anomaly is described by
addressing the concept of Cumulated Anomaly in this
paper. Dubiety-Determining Model (DDM), which is a
detection model basing on statistical and fuzzy set
theories for Cumulated Anomaly, is proposed. DDM
can measure the dubiety degree of each database
transaction quantitatively. Software system
architecture to support the DDM for monitoring
database transactions is designed. We also
implemented the system and tested it. Our
experimental results show that the DDM method is
feasible and effective
On Black Hole Stability in Critical Gravities
We consider extended cosmological gravities with Ricci tensor and scalar
squared terms in diverse dimensions. These theories admit solutions of Einstein
metrics, including the Schwarzschild-Tangherlini AdS black holes, whose mass
and entropy vanish at the critical point. We perform linearized analysis around
the black holes and show that in general the spectrum consists of the usual
spin-2 massless and ghost massive modes. We demonstrate that there is no
exponentially-growing tachyon mode in the black holes. At the critical point,
the massless spin-2 modes have zero energy whilst the massive spin-2 modes are
replaced by the log modes. There always exist certain linear combination of
massless and log modes that has negative energy. Thus the stability of the
black holes requires that the log modes to be truncated out by the boundary
condition.Comment: 16 pages, minor corrections, further comments and references adde
Interacting Intersections
Intersecting p-branes can be viewed as higher-dimensional interpretations of
multi-charge extremal p-branes, where some of the individual p-branes undergo
diagonal dimensional oxidation, while the others oxidise vertically. Although
the naive vertical oxidation of a single p-brane gives a continuum of p-branes,
a more natural description arises if one considers a periodic array of p-branes
in the higher dimension, implying a dependence on the compactification
coordinates. This still reduces to the single lower-dimensional p-brane when
viewed at distances large compared with the period. Applying the same logic to
the multi-charge solutions, we are led to consider more general classes of
intersecting p-brane solutions, again depending on the compactification
coordinates, which turn out to be described by interacting functions rather
than independent harmonic functions. These new solutions also provide a more
satisfactory interpretation for the lower-dimensional multi-charge p-branes,
which otherwise appear to be nothing more than the improbable coincidence of
charge-centres of individual constituents with zero binding energy.Comment: 20 pages, Latex, references adde
Hunting for a scalar glueball in exclusive B decays
Using flavor SU(3) symmetry for the light quarks validated by the available
experimental data, we propose an intuitive way to hunt for a scalar glueball in
B decays. In the presence of mixing between the glueball and ordinary scalar
mesons, we explore the extraction of the mixing parameters. In particular, we
discuss the implication from the recently available experimental data and show
the sensitivities of B decays as a probe to the scalar structures. The future
Super KEKB factory would allow access to establishing the mixing pattern among
the scalars, and possibly allow one to disentangle the long-standing puzzle
concerning the existence and mixings of the scalar glueball predicted by QCD.Comment: 5 pages, 1 figur
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On defining partition entropy by inequalities
Partition entropy is the numerical metric of uncertainty within
a partition of a finite set, while conditional entropy measures the degree of
difficulty in predicting a decision partition when a condition partition is
provided. Since two direct methods exist for defining conditional entropy
based on its partition entropy, the inequality postulates of monotonicity,
which conditional entropy satisfies, are actually additional constraints on
its entropy. Thus, in this paper partition entropy is defined as a function
of probability distribution, satisfying all the inequalities of not only partition
entropy itself but also its conditional counterpart. These inequality
postulates formalize the intuitive understandings of uncertainty contained
in partitions of finite sets.We study the relationships between these inequalities,
and reduce the redundancies among them. According to two different
definitions of conditional entropy from its partition entropy, the convenient
and unified checking conditions for any partition entropy are presented, respectively.
These properties generalize and illuminate the common nature
of all partition entropies
Crystallographic Distinction between âContactâ and âSeparatedâ Ion Pairs:â Structural Effects on Electronic/ESR Spectra of Alkali-Metal Nitrobenzenides
The classic nitrobenzene anion-radical (NB-⢠or nitrobenzenide) is isolated for the first time as pure crystalline alkali-metal salts. The deliberate use of the supporting ligands 18-crown-6 and [2.2.2]cryptand allows the selective formation of contact ion pairs designated as (crown)M+NB-â˘, where M+ = K+, Rb+, and Cs+, as well as the separated ion pair K(cryptand)+NB-â˘both series of which are structurally characterized by precise low-temperature X-ray crystallography, ESR analysis, and UVâvis spectroscopy. The unusually delocalized structure of NB-⢠in the separated ion pair follows from the drastically shortened NâC bond and marked quinonoidal distortion of the benzenoid ring to signify complete (95%) electronic conjugation with the nitro substituent. On the other hand, the formation of contact ion pairs results in the substantial decrease of electronic conjugation in inverse order with cation size (K+ \u3e Rb+) owing to increased localization of negative charge from partial (NO2) bonding to the alkali-metal cation. Such a loss in electronic conjugation (or reverse charge transfer) may be counterintuitive, but it is in agreement with the distribution of odd-electron spin electron density from the ESR data and with the hypsochromic shift of the characteristic absorption band in the electronic spectra. Most importantly, this crystallographic study underscores the importance of ion-pair structure on the intrinsic property (and thus reactivity) of the component ions - as focused here on the nitrobenzenide anion
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