Benchmarking best manufacturing practices: a study into four sectors of Turkish industry

Reports on a benchmarking study conducted to quantify how well companies operating in various sectors of Turkish industry match up to best practice, both in the practices they adopt and in the operational outcomes that result, and to test the hypothesis that the closer a company is to best practice, the more likely it is for that company to achieve higher business performance. The survey conducted in 1997 and 1998 included 82 companies from the Turkish electronics, cement, automotive sectors and part and component suppliers to the appliance industry. For data gathering. employs the Competitive Strategies and Best Practices Benchmarking Questionnaire, supported ly, some follow-up interviews and one-day site visits. Classifies two small groups of companies as leaders and laggers, depending on how close they were to best practice. Shows that the leaders have performed better than the laggers in adopting best manufacturing practices and in the achievement of high performance La,els. The leaders also have achieved substantially higher business performance than the laggers. Furthermore, observes that large-sized companies outperform the rest both in terms of their success in implementing best manufacturing practices and in achieving high operational outcomes and that there is no appreciable difference between industrial sectors in implementing best manufacturing practices and in achieving high operational outcomes

Parallel Algorithm and Dynamic Exponent for Diffusion-limited Aggregation

A parallel algorithm for ``diffusion-limited aggregation'' (DLA) is described and analyzed from the perspective of computational complexity. The dynamic exponent z of the algorithm is defined with respect to the probabilistic parallel random-access machine (PRAM) model of parallel computation according to $T \sim L^{z}$, where L is the cluster size, T is the running time, and the algorithm uses a number of processors polynomial in L\@. It is argued that z=D-D_2/2, where D is the fractal dimension and D_2 is the second generalized dimension. Simulations of DLA are carried out to measure D_2 and to test scaling assumptions employed in the complexity analysis of the parallel algorithm. It is plausible that the parallel algorithm attains the minimum possible value of the dynamic exponent in which case z characterizes the intrinsic history dependence of DLA.Comment: 24 pages Revtex and 2 figures. A major improvement to the algorithm and smaller dynamic exponent in this versio

Binaries discovered by the SPY project. IV, Five single-lined DA double white dwarfs

We present results from our ongoing follow-up observations of double white dwarf binaries detected in the ESO SN Ia Progenitor SurveY (SPY). We discuss our observing strategy and data analysis and present the orbital solutions of five close double white dwarf binaries: HE0320−1917, HE1511−0448, WD0326−273, WD1013−010 and WD1210+140. Their periods range from 0.44 to 3.22 days. In none of these systems we find any spectral lines originating from the companion. This rules out main sequence companions and indicates that the companion white dwarfs are significantly older and cooler than the bright component. Infrared photometry suggests the presence of a cool, helium-rich white dwarf companion in the binary WD 0326−273. We briefly discuss the consequences of our findings for our understanding of the formation and evolution of double white dwarfs

Stability of Coalescence Hidden variable Fractal Interpolation Surfaces

In the present paper, the stability of Coalescence Hidden variable Fractal Interpolation Surfaces(CHFIS) is established. The estimates on error in approximation of the data generating function by CHFIS are found when there is a perturbation in independent, dependent and hidden variables. It is proved that any small perturbation in any of the variables of generalized interpolation data results in only small perturbation of CHFIS. Our results are likely to be useful in investigations of texture of surfaces arising from the simulation of surfaces of rocks, sea surfaces, clouds and similar natural objects wherein the generating function depends on more than one variable

Método de avaliação de tolerância à toxidez de alumínio em trigo, em condições de hidroponia, na Embrapa Trigo.

bitstream/CNPT-2010/40685/1/p-do67.pd

Simple model for 1/f noise

We present a simple stochastic mechanism which generates pulse trains exhibiting a power law distribution of the pulse intervals and a $1/f^\alpha$ power spectrum over several decades at low frequencies with $\alpha$ close to one. The essential ingredient of our model is a fluctuating threshold which performs a Brownian motion. Whenever an increasing potential $V(t)$ hits the threshold, $V(t)$ is reset to the origin and a pulse is emitted. We show that if $V(t)$ increases linearly in time, the pulse intervals can be approximated by a random walk with multiplicative noise. Our model agrees with recent experiments in neurobiology and explains the high interpulse interval variability and the occurrence of $1/f^\alpha$ noise observed in cortical neurons and earthquake data.Comment: 4 pages, 4 figure

The transcriptional coactivator Querkopf controls adult neurogenesis

The adult mammalian brain maintains populations of neural stem cells within discrete proliferative zones. Understanding of the molecular mechanisms regulating adult neural stem cell function is limited. Here, we show that MYST family histone acetyltransferase Querkopf (Qkf, Myst4, Morf)-deficient mice have cumulative defects in adult neurogenesis in vivo, resulting in declining numbers of olfactory bulb interneurons, a population of neurons produced in large numbers during adulthood. Qkf-deficient mice have fewer neural stem cells and fewer migrating neuroblasts in the rostral migratory stream. Qkf gene expression is strong in the neurogenic subventricular zone. A population enriched in multipotent cells can be isolated from this region on the basis of Qkf gene expression. Neural stem cells/progenitor cells isolated from Qkf mutant mice exhibited a reduced self-renewal capacity and a reduced ability to produce differentiated neurons. Together, our data show that Qkf is essential for normal adult neurogenesis