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Fundamental Building Blocks (fundamental + building_block)
Selected AbstractsA Framework for Facilitating Sourcing and Allocation Decisions for Make-to-Order ItemsDECISION SCIENCES, Issue 4 2004Nagesh N. Murthy ABSTRACT This paper provides a fundamental building block to facilitate sourcing and allocation decisions for make-to-order items. We specifically address the buyer's vendor selection problem for make-to-order items where the goal is to minimize sourcing and purchasing costs in the presence of fixed costs, shared capacity constraints, and volume-based discounts for bundles of items. The potential suppliers for make-to-order items provide quotes in the form of single sealed bids or participate in a dynamic auction involving open bids. A solution to our problem can be used to determine winning bids amongst the single sealed bids or winners at each stage of a dynamic auction. Due to the computational complexity of this problem, we develop a heuristic procedure based on Lagrangian relaxation technique to solve the problem. The computational results show that the procedure is effective under a variety of scenarios. The average gap across 2,250 problem instances is 4.65%. [source] The next economy: from dead carbon to living carbonJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2006David Morris Abstract In the early part of the 19th century, the global economy was largely based on carbon extracted directly or indirectly (via animals) from plants. The infant science of chemistry distinguished between products made from vegetables and those made from minerals, in effect, distinguishing between living carbon and dead carbon. By the mid 19th century, however, chemists had adopted a different terminology. Both dead carbon and living carbon, from that time, were lumped together as organic. During the next century the hydrocarbon displaced the carbohydrate as the fundamental building block of industrial societies. But at the dawn of the 21st century, a combination of technological, resource and political developments encouraged a renewed distinction between living and dead carbon and the emergence of a new carbohydrate economy. Copyright © 2006 Society of Chemical Industry [source] Halo model at its best: constraints on conditional luminosity functions from measured galaxy statisticsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2006Asantha Cooray ABSTRACT Using the conditional luminosity function (CLF; the luminosity distribution of galaxies in a dark matter halo) as the fundamental building block, we present an empirical model for the galaxy distribution. The model predictions are compared with the published luminosity function (LF) and clustering statistics from the Sloan Digital Sky Survey (SDSS) at low redshifts, galaxy correlation functions from the Classifying Objects by Medium-Band Observations 17 (COMBO-17) survey at a redshift of 0.6, the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey at a redshift of unity, the Great Observatories Deep Origins Survey (GOODS) at a redshift around 3 and the Subaru/XMM,Newton Deep Field data at a redshift of 4. The comparison with statistical measurements allows us to constrain certain parameters related to analytical descriptions on the relation between a dark matter halo and its central galaxy luminosity, its satellite galaxy luminosity, and the fraction of early- and late-type galaxies of that halo. With the SDSS r -band LF at Mr < ,17, the lognormal scatter in the central galaxy luminosity at a given halo mass in the central galaxy,halo mass, Lc(M), relation is constrained to be 0.17+0.02,0.01, with 1, errors here and below. For the same galaxy sample, we find no evidence for a low-mass cut-off in the appearance of a single central galaxy in dark matter haloes, with the 68 per cent confidence level upper limit on the minimum mass of dark matter haloes to host a central galaxy, with luminosity Mr < ,17, is 2 × 1010 h,1 M,. If the total luminosity of a dark matter halo varies with halo mass as Lc(M) (M/Msat),s when M > Msat, using SDSS data, we find that Msat= (1.2+2.9,1.1) × 1013 h,1 M, and power-law slope ,s= 0.56+0.19,0.17 for galaxies with Mr < ,17 at z < 0.1. At z, 0.6, the COMBO-17 data allows these parameters for MB < ,18 galaxies to be constrained as (3.3+4.9,3.0) × 1013 h,1 M, and (0.62+0.33,0.27), respectively. At z, 4, Subaru measurements constrain these parameters for MB < ,18.5 galaxies as (4.12+5.90,4.08) × 1012 h,1 M, and (0.55+0.32,0.35), respectively. The redshift evolution associated with these parameters can be described as a combination of the evolution associated with the halo mass function and the luminosity,halo mass relation. The single parameter well constrained by clustering measurements is the average of the total satellite galaxy luminosity corresponding to the dark matter halo distribution probed by the galaxy sample. For SDSS, ,Lsat,= (2.1+0.8,0.4) × 1010 h,2 L,, while for GOODS at z, 3, ,Lsat, < 2 × 1011 h,2 L,. For SDSS, the fraction of galaxies that appear as satellites is 0.13+0.03,0.03, 0.11+0.05,0.02, 0.11+0.12,0.03 and 0.12+0.33,0.05 for galaxies with luminosities in the r, band from ,22 to ,21, ,21 to ,20, ,20 to ,19 and ,19 to ,18, respectively. In addition to constraints on central and satellite CLFs, we also determine model parameters of the analytical relations that describe the fraction of early- and late-type galaxies in dark matter haloes. We use our CLFs to establish the probability distribution of halo mass in which galaxies of a given luminosity could be found either at halo centres or as satellites. Finally, to help establish further properties of the galaxy distribution, we propose the measurement of cross-clustering between galaxies divided into two distinctly different luminosity bins. Our analysis shows how CLFs provide a stronger foundation to built-up analytical models of the galaxy distribution when compared with models based on the halo occupation number alone. [source] ON THE ROLE OF THE GROWTH OPTIMAL PORTFOLIO IN FINANCEAUSTRALIAN ECONOMIC PAPERS, Issue 4 2005Article first published online: 6 DEC 200, ECKHARD PLATEN The paper discusses various roles that the growth optimal portfolio (GOP) plays in finance. For the case of a continuous market we show how the GOP can be interpreted as a fundamental building block in financial market modeling, portfolio optimisation, contingent claim pricing and risk measurement. On the basis of a portfolio selection theorem, optimal portfolios are derived. These allocate funds into the GOP and the savings account. A risk aversion coefficient is introduced, controlling the amount invested in the savings account, which allows to characterize portfolio strategies that maximise expected utilities. Natural conditions are formulated under which the GOP appears as the market portfolio. A derivation of the intertemporal capital asset pricing model is given without relying on Markovianity, equilibrium arguments or utility functions. Fair contingent claim pricing, with the GOP as numeraire portfolio, is shown to generalise risk neutral and actuarial pricing. Finally, the GOP is described in various ways as the best performing portfolio. [source] Ultrafine Single-Crystalline Gold Nanowire Arrays by Oriented Attachment,ADVANCED MATERIALS, Issue 14 2007A. Halder Ultrafine single-crystalline gold nanowires (see figure) are synthesized by oriented attachment of nanoparticles in the solution phase. An amine capping agent is preferentially removed from the {111} planes, which causes the wires to form by fusion along these planes. Such nanowires can be used as the fundamental building blocks for nanoelectronics, and will enable basic studies on electric transport in one-dimensional structures to be carried out. [source] Biological evaluation and comparison of three different procedures for labelling of amino acids tyrosine and lysine with technetium-99mJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 3 2007D. Djoki Abstract The 99mTc-labelling of the amino acids tyrosine (Tyr) and lysine (Lys), fundamental building blocks of proteins and peptides, as well as biological properties of the labelled compounds are investigated. Three different approaches for the labelling with 99mTc have been investigated: direct reduction with stannous tin in the presence of the amino acids, the preformed chelate approach through polydentate chelates DTPA and GH, and the ,organometallic approach' using [99m Tc(CO)3(H2O)3]+ precursor. The direct labelling approach was not successful and the yield was poor. In the presence of DTPA and GH, the labelling efficiency was between 43.6 and 97.8%, depending on the amino acid and the polydentate chelate. The use of [99mTc(CO)3(H2O)3]+ precursor point at the formation of 99m Tc(I) co-ordinated complexes with high yield. In this approach, pH and heating influenced the yields. The results of organ distribution study for [99mTc(Tyr)(H2O)(CO)3] and [99mTc(Lys)(H2O)(CO)3] show accumulation in liver, kidneys and intestine. Copyright © 2007 John Wiley & Sons, Ltd. [source] Conceptual approaches for defining data, information, and knowledgeJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 4 2007Chaim Zins The field of Information Science is constantly changing. Therefore, information scientists are required to regularly review,and if necessary,redefine its fundamental building blocks. This article is one of a group of four articles, which resulted from a Critical Delphi study conducted in 2003,2005. The study, "Knowledge Map of Information Science," was aimed at exploring the foundations of information science. The international panel was composed of 57 leading scholars from 16 countries, who represent (almost) all the major subfields and important aspects of the field. This particular article documents 130 definitions of data, information, and knowledge formulated by 45 scholars, and maps the major conceptual approaches for defining these three key concepts. [source] Bond analyses of borates from the Inorganic Crystal Structure DatabaseACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2006Daqiu Yu Various fundamental building blocks (FBBs) are observed in the crystallographic structures of oxoborates available in the Inorganic Crystal Structure Database, Version 1.3.3 (2004); the occurrence of borate groups with low complexity is dominant. Bond-valence parameters d0 of B,O bonds in 758 oxoborates with various FBBs have been calculated using the bond-valence sum model. Some discrepancies in the d0 values obviously occur if the detailed configurations of FBBs in borate crystals are considered; d0 is sensitive to the chemical bonding structure of B atoms in the crystallographic framework. Moreover, d0 values are affected by the existence of interstitial atoms and the substitution of other anionic groups. In addition, the d0 parameters for B,N, B,S, B,P and B,F bonds are also calculated statistically. Some suitable d0 data for various borate FBBs are recommended according to their particular configurations, especially for those with low complexity. On the basis of the proposed linear relationship between calculated nonlinear optical (NLO) coefficients of borates and the current d0 values for various FBBs, it is found that the d0 values may be regarded as a useful parameter for pre-investigating the NLO properties of borates, leading to an efficient structural evaluation and design of novel borates. [source] A triclinic crystal form of Escherichia coli 4-diphosphocytidyl-2C -methyl- d -erythritol kinase and reassessment of the quaternary structureACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2010Justyna Kalinowska-T 4-Diphosphocytidyl-2C -methyl- d -erythritol kinase (IspE; EC 2.7.1.148) contributes to the 1-deoxy- d -xylulose 5-phosphate or mevalonate-independent biosynthetic pathway that produces the isomers isopentenyl diphosphate and dimethylallyl diphosphate. These five-carbon compounds are the fundamental building blocks for the biosynthesis of isoprenoids. The mevalonate-independent pathway does not occur in humans, but is present and has been shown to be essential in many dangerous pathogens, i.e. Plasmodium species, which cause malaria, and Gram-negative bacteria. Thus, the enzymes involved in this pathway have attracted attention as potential drug targets. IspE produces 4-diphosphosphocytidyl-2C -methyl- d -erythritol 2-phosphate by ATP-dependent phosphorylation of 4-diphosphocytidyl-2C -methyl- d -erythritol. A triclinic crystal structure of the Escherichia coli IspE,ADP complex with two molecules in the asymmetric unit was determined at 2,Å resolution and compared with a monoclinic crystal form of a ternary complex of E. coli IspE also with two molecules in the asymmetric unit. The molecular packing is different in the two forms. In the asymmetric unit of the triclinic crystal form the substrate-binding sites of IspE are occluded by structural elements of the partner, suggesting that the `triclinic dimer' is an artefact of the crystal lattice. The surface area of interaction in the triclinic form is almost double that observed in the monoclinic form, implying that the dimeric assembly in the monoclinic form may also be an artifact of crystallization. [source] High-throughput localization of organelle proteins by mass spectrometry: a quantum leap for cell biologyBIOESSAYS, Issue 8 2006Denise J.L. Tan Cells are the fundamental building blocks of organisms and their organization holds the key to our understanding of the processes that control Development and Physiology as well as the mechanisms that underlie disease. Traditional methods of analysis of subcellular structure have relied on the purification of organelles and the painstaking biochemical description of their components. The arrival of high-throughput genomic and, more significantly, proteomic technologies has opened hereto unforeseen possibilities for this task. Recently two reports(1,2) show how much can be gleaned from the combination of analytical centrifugation, mass spectrometry and advanced statistical techniques focused on a high-throughput analysis of the content and organization of plant and animal cells. The results reveal intriguing possibilities for the future and the possibility of mapping much of the known proteome onto our current map of the cell. BioEssays 28: 780,784, 2006. © 2006 Wiley Periodicals, Inc. [source] | |||||||||||||