Interference Channel with Intermittent Feedback

We investigate how to exploit intermittent feedback for interference management. Focusing on the two-user linear deterministic interference channel, we completely characterize the capacity region. We find that the characterization only depends on the forward channel parameters and the marginal probability distribution of each feedback link. The scheme we propose makes use of block Markov encoding and quantize-map-and-forward at the transmitters, and backward decoding at the receivers. Matching outer bounds are derived based on novel genie-aided techniques. As a consequence, the perfect-feedback capacity can be achieved once the two feedback links are active with large enough probabilities.Comment: Extended version of the same-titled paper that appears in IEEE International Symposium on Information Theory (ISIT) 201

Usb Password Generator Berbasis ATMega8 Untuk Autentifikasi User

Semakin berkembangnya waktu, komputer sudah menjadi hal yang biasa dan mendarah daging. Kebanyakan dari seluruh aktivitas manusia menggunakan komputer dan dibantu komputer. Oleh karena hal itu, keamanan sangat diperlukan dalam pemakaian komputer dan kita biasanya akan mendengar kata password. Password sering membuat orang lebih sering melakukan kesalahan dikarenakan ingin membuat password yang panjang ataupun bermacam-macam. Disini penulis akan membuat suatu USB otomatis yang berisi password untuk autentikasi user

Force Modulating Dynamic Disorder: Physical Theory of Catch-slip bond Transitions in Receptor-Ligand Forced Dissociation Experiments

Recently experiments showed that some adhesive receptor-ligand complexes increase their lifetimes when they are stretched by mechanical force, while the force increase beyond some thresholds their lifetimes decrease. Several specific chemical kinetic models have been developed to explain the intriguing transitions from the "catch-bonds" to the "slip-bonds". In this work we suggest that the counterintuitive forced dissociation of the complexes is a typical rate process with dynamic disorder. An uniform one-dimension force modulating Agmon-Hopfield model is used to quantitatively describe the transitions observed in the single bond P-selctin glycoprotein ligand 1(PSGL-1)$-$P-selectin forced dissociation experiments, which were respectively carried out on the constant force [Marshall, {\it et al.}, (2003) Nature {\bf 423}, 190-193] and the force steady- or jump-ramp [Evans {\it et al.}, (2004) Proc. Natl. Acad. Sci. USA {\bf 98}, 11281-11286] modes. Our calculation shows that the novel catch-slip bond transition arises from a competition of the two components of external applied force along the dissociation reaction coordinate and the complex conformational coordinate: the former accelerates the dissociation by lowering the height of the energy barrier between the bound and free states (slip), while the later stabilizes the complex by dragging the system to the higher barrier height (catch).Comment: 8 pages, 3 figures, submitte

Spheres and Prolate and Oblate Ellipsoids from an Analytical Solution of Spontaneous Curvature Fluid Membrane Model

An analytic solution for Helfrich spontaneous curvature membrane model (H. Naito, M.Okuda and Ou-Yang Zhong-Can, Phys. Rev. E {\bf 48}, 2304 (1993); {\bf 54}, 2816 (1996)), which has a conspicuous feature of representing the circular biconcave shape, is studied. Results show that the solution in fact describes a family of shapes, which can be classified as: i) the flat plane (trivial case), ii) the sphere, iii) the prolate ellipsoid, iv) the capped cylinder, v) the oblate ellipsoid, vi) the circular biconcave shape, vii) the self-intersecting inverted circular biconcave shape, and viii) the self-intersecting nodoidlike cylinder. Among the closed shapes (ii)-(vii), a circular biconcave shape is the one with the minimum of local curvature energy.Comment: 11 pages, 11 figures. Phys. Rev. E (to appear in Sept. 1999

The impact of service quality on customer satisfaction and repurchase intention in the turkish banking sector: an analysis using structural equation modeling

Bu çalışma Türkiye’de özel bankalar tarafından sunulan hizmetlerin kalitesine yönelik müşteri beklentilerini ve algılarını değerlendirmeyi ve yapısal eşitlik modeli ile banka hizmet kalitesi, müşteri tatmini ve tekrar satın alma niyeti arasındaki ilişkiyi incelemeyi amaçlamaktadır. Araştırmada veri SERVQUAL ölçeği kullanılarak dünyanın en değerli 100 banka markası arasında yer alan özel bir bankanın 500 müşterisinden yüz yüze anket yöntemi ile toplanmıştır. Analiz sonuçları müşterilerin hizmet kalitesi algılamalarının beklentilerinin altında kaldığını ve en büyük farkın yanıt verebilirlik en küçük farkın ise somutluk boyutunda olduğunu ortaya koymaktadır. Ayrıca, kaliteli hizmet sunumunun müşterinin hizmeti tekrar satın alma niyetini doğrudan etkilemediği, buna karşın, müşteri tatminini artırarak müşterinin tekrar satın alma niyetini dolaylı ve güçlü bir şekilde etkilediğini göstermektedir. Bu sonuç müşteri tatmininin tekrar satın alma niyetine aracılık ettiğini doğrulamaktadır.The aim of this paper is two-fold: firstly, to assess customers’ expectations and perceptions towards the quality of services provided by private banks in Turkey and, secondly, to investigate the relationships between service quality, satisfaction, and repurchase intention for bank customers through a structural equation model. Data were collected by face to face interviews with 500 customers of a private bank listed in world’s most valuable 100 banking brands using the SERVQUAL method. Results revealed that customers’ perceptions of service quality fell short of their expectations, with the responsiveness dimension having the largest gap and the tangibles dimension having the smallest gap. Moreover, although the service quality did not have a direct effect on customer repurchase intention, it did have an indirect influence on customer repurchase intention via customer satisfaction. Results confirmed the mediator effect of customer satisfaction

Large deformation of spherical vesicle studied by perturbation theory and Surface evolver

With tangent angle perturbation approach the axial symmetry deformation of a spherical vesicle in large under the pressure changes is studied by the elasticity theory of Helfrich spontaneous curvature model.Three main results in axial symmetry shape: biconcave shape, peanut shape, and one type of myelin are obtained. These axial symmetry morphology deformations are in agreement with those observed in lipsome experiments by dark-field light microscopy [Hotani, J. Mol. Biol. 178, (1984) 113] and in the red blood cell with two thin filaments (myelin) observed in living state (see, Bessis, Living Blood Cells and Their Ultrastructure, Springer-Verlag, 1973). Furthermore, the biconcave shape and peanut shape can be simulated with the help of a powerful software, Surface Evolver [Brakke, Exp. Math. 1, 141 (1992) 141], in which the spontaneous curvature can be easy taken into account.Comment: 16 pages, 6 EPS figures and 2 PS figure

Optimal entanglement witnesses based on local orthogonal observables

We show that the entanglement witnesses based on local orthogonal observables which are introduced in [S. Yu and N.-L. Liu, Phys. Rev. Lett. 95, 150504 (2005)] and [O. G\"uhne, M. Mechler, G. T\'oth and P. Adam, Phys. Rev. A 74, 010301 (2006)] in linear and nonlinear forms can be optimized, respectively. As applications, we calculate the optimal nonlinear witnesses of pure bipartite states and show a lower bound on the I-concurrence of bipartite higher dimensional systems with our method.Comment: 6 pages, 1 figure; minor changes, references adde