2,020 research outputs found
Trading Inefficiencies in California's Electricity Markets
We study price convergence between the two major markets for wholesale electricity in California from their deregulation in April 1998 through November 2000, nearly the end of trading in one market. We would expect profit-maximizing traders to have eliminated persistent price differences between the markets. Institutional impediments and traders' incomplete understanding of the markets, however, could have delayed or prevented price convergence. We find that the two benchmark electricity prices in California -- the Power Exchange's day-ahead price and the Independent System Operator's real-time price -- differed substantially after the markets opened but then appeared to be converging by the beginning of 2000. Starting in May 2000, however, price levels and price differences increased dramatically. We consider several explanations for the significant price differences and conclude that rapidly changing market rules and market fundamentals, including one buyer's attempt to exercise a form of monopsony power, made it difficult for traders to take advantage of opportunities that ex post appear to have been profitable.
Das Biokontrollsystem in Österreich
Österreich hat ein bereits weit entwickeltes Bio-Kontrollsystem – trotzdem gibt es Schwachstellen. Die Autoren benennen den Handlungsbedarf zu seiner Optimierung
The Half-lives of La and La
The half-lives of La and La were determined via gamma
spectroscopy and high-precision ionization chamber measurements. The results
are 18.930(6) h for La and 4.59(4) h for La compared to the
previously compiled values of 19.5(2) h and 4.8(2) h, respectively. The new
results represent an improvement in the precision and accuracy of both values.
These lanthanum isotopes comprise a medically interesting system with positron
emitter La and Auger electron emitter La forming a matched pair
for internal diagnostics and therapeutics. The precise half-lives are necessary
for proper evaluation of their value in medicine and for a more representative
tabulation of nuclear data.Comment: 11 pages, 3 figure
Temperature induced phase averaging in one-dimensional mesoscopic systems
We analyse phase averaging in one-dimensional interacting mesoscopic systems
with several barriers and show that for incommensurate positions an independent
average over several phases can be induced by finite temperature. For three
strong barriers with conductances G_i and mutual distances larger than the
thermal length, we obtain G ~ sqrt{G_1 G_2 G_3} for the total conductance G.
For an interacting wire, this implies power laws in G(T) with novel exponents,
which we propose as an experimental fingerprint to distinguish temperature
induced phase averaging from dephasing.Comment: 6 pages, 5 figures; added one figure; slightly extende
Comparing the efficiency of base and multiplicative selection indices for yield and quality traits in Cassava: Article Retracted by the Authors
The efficiency of two selection indices; base index and the multiplicative index was compared to determine the effectiveness of each in identifying superior genotypes in cassava (Manihot esculent Crantz) population. Genotypic data on various yield and quality traits among 570 cassava genotypes were used to construct these selection indices. The efficiency of these indices was compared by determining the performance means of each genotype for studied traits and computing selection differentials of each index. Best linear unbiased predictions (BLUPs) for dry matter content and harvest index were also used for comparison of the two selection indices. The base index produced high-performance means of all five studied traits and proved to be more efficient compared to the multiplicative index in the improvement of cassava genotypes. In addition, the base index produced high selection differentials for three out of five studied traits. It was concluded that the base index is useful in cassava germplasm selectio
Adhesion of electrolessly deposited Ni(P) layers on alumina ceramic II. Interface characterization
The interface microstructure and interface chem. of electrolessly deposited Ni(P) on alumina ceramics is studied to obtain insight into the influence of mol. interactions upon the adhesion. Detailed static secondary-ion-mass spectrometry, XPS, Auger electron spectroscopy, and transmission electron microscopy (TEM) analyses have been carried out with samples with various roughness, of which the mech. analyses are described in a companion article. TEM cross-section micrographs showed a close contact between the two phases on a nanometer scale for all sample types. In addn., a 1-2-nm-thick interfacial layer was obsd. This layer consists of nucleation material and compds. from the metalization soln. Fracture surface analyses showed that fracture takes place through this layer, which is therefore considered to be the weak boundary layer in this system. The presence of this weak boundary layer explains the importance of substrate surface roughness and mech. interlocking for the fracture energy. [on SciFinder (R)
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