A Bio-Inspired 128 × 128 Complementary Metal–Oxide–Semiconductor Vision Chip for Edge Detection with Signal Processing Circuit Separated from Photo-Sensing Circuit

In this paper, a vision chip for edge detection based on the structure of biological retina is introduced. The key advantage of retinal structure is speed of operation. However, bio-inspired vision chips have suffered from low resolution which is caused by their complex circuit structure. To sufficiently improve the resolution for real application, the circuits for analog processing were separated from circuits for image capturing. In addition, we compensated the low speed problem of operation which is caused by bottleneck of data transfer between photo-sensors and analog processing circuit by adding a reset decoder. The vision chip was fabricated using 0.35 μm 2-poly 4-metal complementary metal---oxide---semiconductor technology. Using the vision chip, we could obtain a contrast-enhanced image without any other cost-increase for fabrication of chips. Then, the edge image was easily achieved by thresholding the previous contrast-enhanced image.     

Configuration of fully replicated distributed database system over wide area networks

The cost and performance of a distributed database system (DDS) depends on data distribution and database server configuration across the network. An inappropriate allocation of data and database severs could result in a DDS which is either too costly or unacceptably slow. This paper models the optimal configuration of fully replicated DDS. The problem is formulated as an integer linear programming problem and a solution procedure based on Lagrangian relaxation and subgradient optimization is proposed. The proposed solution procedure was computationally tested under various scenarios regarding communication, processor costs, and transaction characteristics.     

Index abstracts

Other Index

Index abstracts     

A new metal-organic open framework consisting of threefold parallel interwoven (6,3) nets

Threefold parallel interwoven (6,3) nets were assembled from Ni(II) cyclam complex and 1,3,5-tris[2-(4-carboxyphenyl)-1-ethynyl]benzene. The network generates triangular voids of effective size ca. 18.4 x 14.7 x 9.5 A. It contains 35% free volume of the crystal volume and is stable up to 300 degrees C.     

Monomeric rhodium(II) catalysts for the preparation of aziridines and enantioselective formation of cyclopropanes from ethyl diazoacetate at room temperature

A family of bis(oxazoline) complexes of coordinatively unsaturated monomeric rhodium(II) (2a,b, 3a,b) are described. These complexes serve as catalysts for cyclopropanation of olefins by ethyl diazoacetate, giving excellent yields (66-94%). Enantioselectivities for the cis product isomers are good (61-84%). The reaction shows an unusual preference for formation of the cis isomers. Catalytic aziridination of N-aryl imines with ethyl diazoacetate is also described.     

Dexamethasone differentiates NG108-15 cells through cyclooxygenase 1 induction

Cyclooxygenase (COX) is a key enzyme in the conversion of arachidonic acid into prostanoids which participate in various cellular functions including apoptosis, mitogenesis, inflammation, immune modulation and differentiation. Moreover, the synthetic glucocorticoid, dexamethasone has immune modulating and anti-inflammatory effects in vivo. Recently, dexamethasone was found to enhance retinoic acid-induced neuronal differentiation. In this study, we investigated the mechanisms of dexamethasone-mediated neuronal differentiation. Immunoblotting and morphological analysis demonstrated that dexamethasone induced neuronal differentiation through COX 1 induction. This phenomenon was inhibited by indomethacin, a COX inhibitor. In addition, the addition of exogenous prostaglandin E2 (PGE2), a substance produced by the COX-mediated pathway, triggered neurite outgrowth of cells treated with COX inhibitor. Taken together, COX 1 appears to play an important role in dexamethasone-mediated neuronal differentiation.     

Mechanically switchable photonic crystal filter with either all-pass transmission or flat-top reflection characteristics

We theoretically introduce a new type of optical all-pass filter based on guided resonance in coupled photonic crystal slabs. The filter exhibits near-complete transmission for both on- and off-resonant frequencies and yet generates large resonant group delay. We further show that such a filter can be mechanically switched into a flat-top band rejection filter.