When the cohomology ring of a generalized Bott manifold with Q-coefficient is isomorphic to that of a product of complex projective spaces CP^<n_<i>> , the generalized Bott manifold is said to be Q-trivial. We find a necessary and sufficient condition for a generalized Bott manifold to be Q-trivial. In particular, every Q-trivial generalized Bott manifold is diffeomorphic to a Π_<n_<i> > 1> CP^<n_<i>> -bundle over a Q-trivial Bott manifold.

The notion of a toric origami manifold, which weakens the notion of a symplectic toric manifold, was introduced by A. Cannas da Silva, V. Guillemin and A.R. Pires. They showed that toric origami manifolds bijectively correspond to origami templates via moment maps, where an origami template is a collection of Delzant polytopes with some folding data. Like a fan is associated to a Delzant polytope, a multi-fan introduced by A. Hattori and M. Masuda can be associated to an oriented origami template. In this paper, we discuss their relationship and show that any simply connected compact smooth 4-manifold with a smooth action of T ² can be a toric origami manifold. We also characterize products of even dimensional spheres which can be toric origami manifolds.

There has been an increasing interest in analyzing social network services data. However, detecting social topics in the era of information explosion requires state-of-the-art analytics techniques. The geographic clustering analysis based on social topics across provinces, i.e., states, has rarely been studied. Using the Twitter data collected in the United States (US), we detected the social hot topic by using the ratio of word frequency. Also, we found geographic communities by correlating the time series for a set of topic words across US states. The result of the geographic clustering was visualized using the Google Fusion Table. In conclusion, the ratio of word frequency properly detects social topics or breaking news while suppressing daily tweeted small talks or emotional words such as lol, like, and love. We have also demonstrated that a clustering algorithm based on a social topic can be useful in classifying social communities.

Many High-Dynamic-Range (HDR) rendering techniques have been developed. Of these, the image color appearance model, iCAM, is a typical HDR image rendering algorithm. HDR rendering methods normally require a tone compression process and include many color space transformations from the RGB signal of an input image to the RGB signal of output devices for the realistic depiction of a captured image. The iCAM06, which is a refined iCAM, also contains a tone compression step and several color space conversions for HDR image reproduction. On the other hand, the tone compression and frequent color space changes in the iCAM06 cause color distortion, such as a hue shift and saturation reduction of the output image. To solve these problems, this paper proposes a separate color correction method that has no effect on the output luminance values by controlling only the saturation and hue of the color attributes. The color saturation of the output image was compensated for using the compensation gain and the hue shift was corrected using the rotation matrix. The separate color correction method reduces the existing color changes in iCAM06. The compensation gain and rotation matrix for the color correction were formulated based on the relationship between the input and output tristimulus values through the tone compression. The experimental results show that the revised iCAM06 with the proposed method has better performance than the default iCAM06.

We present a multi-channel sampling expansion for signals with selectively tiled band-region. From this we derive an oversampling expansion for any bandpass signal, and show that any finitely many missing samples from two-channel oversampling expansion can always be uniquely recovered. In addition, we find a sufficient condition under which some infinitely many missing samples can be recovered. Numerical stability of the recovery process is also discussed in terms of the oversampling rate and distribution of the missing samples.

A smart meter, a component of smart grid systems, has low computational capability. This is in contrast to data collection units (DCUs) and meter data management servers (MDMSs). In this study, we propose a lightweight signature scheme and an authentication and report protocol that can reduce computational overhead and facilitate efficient operation of these three components in smart grid systems. The proposed signature scheme, called the linear map digital signature scheme (LMDSS), uses properties of linear maps and matrix operations; hence, it has low computational requirements. The proposed protocol is a delegation-based authentication protocol that uses an intermediate node, DCU. Using the proposed protocol, authentication of a DCU can be completed by a hash function. To evaluate the performance of the scheme and protocol, we implemented signature schemes, ours and others, and simulated the proposed protocol to obtain analytical results. We also proved that the scheme is secure by using a random oracle and analyzing the security of the protocol based on possible attack scenarios.

We introduce a mathematical model to study the transport of ions through ion channels. The system is derived in the framework of the energetic variational approach, taking into account the coupling between electrostatics, diffusion, and protein (ion channel) structure. The geometric constraints of the ion channel are introduced through a potential energy controlling the local maximum volume inside the ion channel. A diffusive interface (labeling) deion is also employed to describe the geometric configuration of the channels. The surrounding bath and channel are smoothly connected with the antechamber region by this label function. A corresponding modified Poisson–Nernst–Planck channel system for ion channels is derived using the variational derivatives of the total energy functional. The functional consists of the entropic free energy for diffusion of the ions, the electrostatic potential energy, the repulsive potential energy for the excluded volume effect of the ion particles, and the potential energy for the geometric constraints of the ion channel. For the biological application of such a system, we consider channel recordings of voltage clamp to measure the current flowing through the ion channel. The results of one­dimensional numerical simulations are presented to demonstrate some signature effects of the channel, such as the current output produced by single­step and double­step voltage inputs. Copyright © 2013 John Wiley & Sons, Ltd.

Conclusion: The study showed that combined repetitive transcranial magnetic stimulation (rTMS) on the auditory cortex and prefrontal cortex has more benefit than rTMS on the auditory cortex alone for tinnitus control in patients with depression. Further studies for the most optimal combination of stimulation on both areas are needed. Objective: Recent studies suggest that the neuronal network changes of chronic tinnitus are beyond the auditory pathway. There is increasing evidences for the application of rTMS on multiple brain cortices in addition to the auditory cortex for the treatment of tinnitus. Sequential rTMS was performed on the auditory cortex alone as well as the auditory cortex combined with prefrontal cortex in patients with both chronic tinnitus and depression. Methods: Patients who presented with chronic tinnitus of more than 1 year were enrolled in the present study (seven males, four females; mean age 54 years). To select the site for the rTMS, PET CT was performed. Patients received the first rTMS on the primary auditory cortex for 5 days and on the primary auditory cortex and prefrontal cortex in the second application after tinnitus relapse. The Tinnitus Handicap Inventory (THI), visual analog scale (VAS), and Beck Depression Inventory (BDI) were evaluated before and after rTMS. Results: The mean THI score of the eight patients with depression changed from 77.5 ± 15 to 61.8 ± 20.1 after the second rTMS. There was statistical significance only for the second rTMS. The VAS score changed from 8.6 ± 1.6 to 6.3 ± 1.8 after the first rTMS and from 7.6 ± 2.4 to 4.6 ± 2.7 after the second rTMS, showing statistically significant changes both times. The THI changes after the second rTMS were greater than after the first rTMS, and the changes in VAS score showed a similar pattern. The changes in BDI score, which indicates the severity of depression, showed a variable pattern after rTMS. Patients with mild depression (10≤ BDI score <16, n = 4) showed significant improvement of THI with the second combined rTMS (ΔTHI = 24.5) as compared with the first rTMS on the auditory area (ΔTHI = 6). In contrast, combined rTMS did not show any better improvement on THI (ΔTHI = 6.5) than the first rTMS on the auditory cortex (ΔTHI = 7) in patients without depression (BDI <10, n = 3) and patients with moderate to severe depression (BDI ≥16, n = 4).

We propose the full information minority game (FIMG) in which agents perfectly recognize their impact on the market. For reflecting the impact of agents, we introduce an actual total action and an actual payoff which depend on the agent’s strategies. Unlike the perpetual fluctuating dynamics of the standard minority game, the dynamics of the FIMG settles into one of four steady states after a transient time. We classify steady states of the FIMG and analyze their characteristics. In most cases, the total payoff is maximized, and the total action settles into a periodic state. For measuring the degree of cooperation on the FIMG, we calculate a fraction of total payoff maximization and a mean relaxation time for the dynamics to settle into a steady state whose total payoff is maximized.

We consider the problem of reconstructing a wide sense stationary band-limited process from its local averages taken either at the Nyquist rate or above. As a result we obtain a sufficient condition under which average sampling expansions hold in mean square and for almost all sample functions. Truncation and aliasing errors of the expansion are also discussed.