Apakah Opec Merupakan Kartel?: Pendekatan Kausalitas Granger dalam Kerangka Vector Autoregressive

One would believe that The Organization of Petroleum Exporting Countries (OPEC) is certainly a cartel which curbs production in order to raise the price of its product as well as to share the market among its members. Did energy shock of the 1970\u27s engineered by an effective cartel of OPEC members acting to share the market by controlling output and influencing market prices? One would also expect OPEC\u27s production to significantly affect the market price of oil as the organization is often accused of curbing production in order to raise prices. This paper tries to determine whether OPEC has the power of affecting the market price of oil and or vice versa. This study uses the Toda and Yamamoto (1995) procedure for testing for Granger non-causality in Vector Autoregressive (VAR) models that involves variables that are integrated of an arbitrary order and that are possibly cointegrated. The results indicate that there is no statistically significant causal relationship between real crude oil price and OPEC production in either direction for full sample period 1974 – 2005. Instead, we find that real crude oil price Granger cause OPEC production in 2 different sub samples period, but not in other direction. As overall we reject cartel hypothesis for OPEC as a whole

Structure of Flux Line Lattices with Weak Disorder at Large Length Scales

Dislocation-free decoration images containing up to 80,000 vortices have been obtained on high quality Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+x}$ superconducting single crystals. The observed flux line lattices are in the random manifold regime with a roughening exponent of 0.44 for length scales up to 80-100 lattice constants. At larger length scales, the data exhibit nonequilibrium features that persist for different cooling rates and field histories.Comment: 4 pages, 3 gif images, to appear in PRB rapid communicatio

Ultrabroadband Polarization Insensitive Hybrid using Multiplane Light Conversion

We designed, fabricated and tested an optical hybrid that supports an octave of bandwidth (900-1800 nm) and below 4-dB insertion loss using multiplane light conversion. Measured phase errors are below 3-degree across a measurement bandwidth of 390 nm.Comment: 3 pages, 4 figures, accepted by OFC 202

Building a Fab on a Chip

Semiconductor fabs are large, complex industrial sites with costs for a single facility approaching $10B. In this paper we discuss the possibility of putting the entire functionality of such a fab onto a single silicon chip. We demonstrate a path forward where, for certain applications, especially at the nanometer scale, one can consider using a single chip approach for building devices with significant potential cost savings. In our approach, we build micro versions of the macro machines one typically finds in a fab, and integrating all the components together. We argue that the technology now exists to allow one to build a Fab on a Chip.Fil: Imboden, Matthias. Boston University; Estados UnidosFil: Han, Han. Boston University; Estados UnidosFil: Stark, Thomas. Boston University; Estados UnidosFil: Lowell, Evan. Boston University; Estados UnidosFil: Chang, Jackson. Boston University; Estados UnidosFil: Pardo, Flavio. Bell Labs; Estados UnidosFil: Bolle, Cristian. Bell Labs; Estados UnidosFil: del Corro, Pablo Guillermo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bishop, David J.. Boston University; Estados Unido

Mode-Division Multiplexing over 96 Km of Few-Mode Fiber using Coherent 6x6 MIMO Processing

We report simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber. The channels are successfully recovered by offline DSP based on coherent detection and multiple-input multiple-output processing. A penalty of \u3c 1.2 dB is achieved by using 6x 6 feed-forward equalizers with 120 taps each. The 6x6 impulse-response matrix fully characterizing the few-mode fiber is presented, revealing the coupling characteristics between the modes. The results are obtained using mode multiplexers based on phase plates with a mode selectivity of \u3e 28 dB

Atomic Calligraphy: The Direct Writing of Nanoscale Structures Using a Microelectromechanical System

We present a microelectromechanical system (MEMS) based method for the resist-free patterning of nanostructures. Using a focused ion beam to customize larger MEMS machines, we fabricate apertures with features less than 50 nm in diameter on plates that can be moved with nanometer precision over an area greater than 20 × 20 μm². Depositing thermally evaporated gold atoms though the apertures while moving the plate results in the deposition of nanoscale metal patterns. Adding a shutter positioned micrometers above the aperture enables high speed control of not only where but also when atoms are deposited. With this shutter, different-sized apertures can be opened and closed selectively for nanostructure fabrication with features ranging from nano- to micrometers in scale. The ability to evaporate materials with high precision, and thereby fabricate circuits and structures in situ, enables new kinds of experiments based on the interactions of a small number of atoms and eventually even single atoms

Ultrabroadband Polarization Insensitive Hybrid using Multiplane Light Conversion

We designed, fabricated and tested an optical hybrid that supports an octave of bandwidth (900-1800 nm) and below 4-dB insertion loss using multiplane light conversion. Measured phase errors are below 3° across a measurement bandwidth of 390 nm

Ultrabroadband polarization insensitive hybrid using multiplane light conversion

We designed, fabricated and tested an optical hybrid that supports an octave of bandwidth (900-1800 nm) and below 4-dB insertion loss using multiplane light conversion. Measured phase errors are below 3ºacross a measurement bandwidth of 390 nm