Allocation of Marketing Effort Among <Emphasis Type="Italic">P</Emphasis> Substitutional Products in <Emphasis Type="Italic">N</Emphasis> Territories<Superscript>†</Superscript>

Frequently, companies face the problem of allocating a given marketing budget in order to maximize their total returns. In this paper we examine the problem of allocating marketing effort, such as advertising, among P substitutional products, distributed in N different sales territories. Two models are discussed. In the first model it is assumed that at most one product is promoted in each sales territory. It is shown that a simple algorithm leads to at least a local optimum in a finite number of steps. In the second model, the restriction of one product per territory is eliminated. Applying a concept of effective effort, the model is transformed to an equivalent separable programming problem, solvable by a “single-pass” algorithm for various forms of response functions. Furthermore, a concept of successive modifications of the objective function is discussed.     

Design of Stacked Self-Healing Rings Using a Genetic Algorithm

Ring structures in telecommunications are taking on increasing importance because of their self-healing properties. We consider a ring design problem in which several stacked self-healing rings (SHRs) follow the same route, and, thus, pass through the same set of nodes. Traffic can be exchanged among these stacked rings at a designated hub node. Each non-hub node may be connected to multiple rings. It is necessary to determine to which rings each node should be connected, and how traffic should be routed on the rings. The objective is to optimize the tradeoff between the costs for connecting nodes to rings and the costs for routing demand on multiple rings. We describe a genetic algorithm that finds heuristic solutions for this problem. The initial generation of solutions includes randomly-generated solutions, complemented by seed solutions obtained by applying a greedy randomized adaptive search procedure (GRASP) to two related problems. Subsequent generations are created by recombining pairs of parent solutions. Computational experiments compare the genetic algorithm with a commercial integer programming package.     

Structural and dynamical properties of iridium surfaces: First principles and molecular dynamics investigations

The structural and dynamical properties of Ir(1 0 0) clean surface are investigated in the temperature range 100-1100 K. We performed molecular dynamics (MD) simulations using the interaction potential energies obtained from the density-functional theory (DFT) and plane-wave pseudopotential (PWPP) method. The obtained contraction of the first interlayer distance, d₁₂ , decreases from −4.94% at 100 K to −4.84% at 1100 K. This decrease deviates by 11.8% at 100 K to 13.6% at 1100 K, from that at 0 K (−5.6%). The expansion of the second interlayer distance, d₂₃, however increases from 0.89% at 100 K to 1% at 1100 K, causing a deviation that ranges from −11% to 0% from that at 0 K (1%). The deviation of the calculated surface vibrational frequencies and surface relaxations over the entire range of temperatures (100-1100 K) is rather modest as a result of small anharmonic effects of the surface.     

Diagnostic value of different antigenic fractions of hydatid cyst fluid from camel and sheep in Kingdom of Saudi Arabia

Hydatid cyst fluids (HCF) crude extracts from camels and sheep slaughtered in Riyadh region, KSA were subjected to Sodium Dodecyl Sulfate–Polyacrylamide Gel Electrophoresis (SDS–PAGE) and Western blot analysis. Sera from 17 confirmed human cases of hydatidosis, 25 patients with other parasitic infections and 10 clinically healthy subjects were used to evaluate the diagnostic value of the different antigenic fractions of these extracts. Immunoblotting results revealed that, at least 11 major discrete protein fractions (110–8 kDa) were recognized by sera from hydatidosis patients, sera from patients with other parasitic diseases showed cross-reactivity with few of these bands. The cluster of bands (38–35 kDa) that may be a breakdown of “Arc 5” antigen (39–38 kDa) was detected by 100% and 94% of sera from hydatidosis cases with HCF extracts from camel and sheep, respectively. This cluster showed also some cross reactivity (20% and 8%) with control sera from patients with other parasitic infections with camel and sheep HCF extracts, respectively. Polypeptides at 24–22, 16 and 8 kDa which may probably correspond to antigen B subunits were also identified by all samples from hydatidosis patients with sheep HCF extracts and by 100%, 65% and 74% with camel HCF extracts respectively. Sera from control subjects did not react with any of these polypeptides (24–22, 16 and 8 kDa). According to our results, the identified molecular weight bands (16 and 8 kDa using HCF crude extracts from sheep and 24–22 kDa using HCF crude extracts either from camel or sheep) represent good candidates for immunodiagnosis of hydatidosis.     

Synthesis of a halo-methylphenylene periphery-functionalized triazine-based dendritic molecule with a 3,3′-dimethyl-biphenyl linker using tris(halo-methylphenylene)triazines as building blocks

A tris(bromo-methylphenylene)triazine and its corresponding phosphine oxide derivative have been synthesized; the latter compound was found to be a potent ligand for the hydroformylation reaction. Suzuki coupling of the mono-pinacolboronate derivative of the former compound with a tris(iodo-methylphenylene)triazine was possible at two of the three iodine atoms, yielding a bromo- and iodo-methylphenylene periphery-functionalized triazine-based dendritic molecule with a 3,3′-dimethyl-biphenyl linker.     

Use of alpha spectrometry for analysis of U-isotopes in some granite samples

The present study aims to use the ??-spectrometry, at NMA. A radiochemical technique [1, 2] for analysis of U-isotopes was carried out for some granite samples from Gabal Gattar and El Missikat localities and also for some reference soil samples of IAEA. Several steps of sample preparation, radiochemical separation, and source preparation were performed before analysis. The concerned sample was leached by HNO₃, HF and H₂O₂ acids after ashing. The ashed sample was spiked with uranium tracer (²³²U) for chemical yield and activity calculation. Then uranium was extracted from the matrix elements with trioctylphosphine oxide (TOPO) and stripped with 1 M NH₄F/0.1 M HCl solution. The uranium fraction was purified by co-precipitation with LaF₃ to ensure complete removal of thorium and traces of resolution degrading elements. This was followed by a final clean-up step using an anion exchange. The pure uranium fraction was electrodeposited on a stainless steel disc from HCl/oxalate solution. The obtained results from the soil reference samples indicate general similarities between the techniques of ??-spectrometers of NMA, EAEA and IAEA for analysis of U-isotopes. The U-isotopes in the granite samples of high radioactivity levels need more attempts after dilution process to be in the limit detection of ??-spectrometry.     

Discrete covalent organic-inorganic hybrids: terpyridine functionalized polyoxometalates obtained by a modular strategy and their metal complexation

The rational design and synthesis of organic-inorganic hybrids as functional molecular materials relies on both the careful conception of building-blocks and the strategy for their assembly. Three families of trialkoxo polyoxometalates (Lindqvist 2, Anderson 3, Dawson 4) grafted with remote terpyridine coordination sites have been synthesized to extend the available building-blocks. These new units can be combined with metal complexes that play a role as (i) chromophores toward charge-separated systems in light-harvesting devices and (ii) coordination motifs for metal-directed self-assembly toward multifunctional molecular hybrid materials. The X-ray crystal structures of polyoxometalate-terpyridine hybrids indicate distances of 21 ? and 19 ? between the two terpyridyl coordination sites in 2 and 3, respectively, with angles between the coordination vectors of 180° and 177.4°, respectively. Lindqvist 2 displays a reduction at -0.52 V vs SCE while Anderson 3 exhibits one reversible oxidation attributed to Mn(III)/Mn(IV) (+0.75 V vs SCE) and a broad wave at -1.28 V vs SCE assigned to the Mn(III)/Mn(II) reduction. Dawson 4 displays several processes on a wide range of potentials (+0.5 to -2.0 V vs SCE) centered on V(V), W(VI) and the organic ligand in order of decreasing potentials. The grafted terpyridine ligands in Anderson 3 and Dawson 4 were successfully coordinated to {PdCl}(+) and {RuCl(3)} moieties, respectively. The polyoxometalates and transition metal complexes retain their intrinsic properties in the final assemblies.     

Dinuclear Ru(II) complexes of bis-(dipyrid-2'-yl)triazine (bis-dpt) ligands as efficient electron reservoirs

A planar bis-dipyrid-2'-yltriazine (bis-dpt) bridging ligand forms dinuclear Ru(II) complexes able to store up to eight electrons upon electrochemical reduction.