Scope economies between indiscriminate and selective urban solid waste collection

Recycling is one possible option within municipal solid waste (MSW) management to deal with the growing quantities of MSW produced. Only a few scholars have analysed the costs of this service and asked the question whether municipal solid waste management service utilities benefit from providing waste disposal and recycling services jointly. This dissertation tries to answer this question in the Portuguese context. In other words, it tries to find whether there are economies of scope in the Portuguese municipal solid waste management market between waste collection and disposal and recycling services. To answer the question, this study estimates a cost function of the municipal solid waste collection and disposal and recycling services in Portugal. Using a panel of 260 Portuguese retail municipal solid waste management service providers observed from 2001 to 2015, a multi-output translog cost function is estimated. The index value for scope economies is -0.27, meaning diseconomies of scope have been found.A reciclagem é uma opção possível na gestão de residuos sólidos urbanos para lidar com a crescente quantidade deste tipo de resíduos que é produzida. Não existem muitos Estudos que tenham analisado este serviço e perguntado se as entidades gestoras de resíduos sólidos urbanos beneficiam do fornecimento simultâneo dos serviços de recolha de lixo e de reciclagem. Esta dissertação procura responder a essa questão no contexto português. Por outras palavras, ela tenta descobrir se existem economias de gama na gestão de resíduos sólidos urbanos no mercado português entre a recolha de resíduos e os serviços de reciclagem. Para responder à questão, este estudo estima uma função de custo para os serviços de recolha de resíduos sólidos urbanos e de reciclagem em Portugal. Usando um painel de 260 entidades gestoras de serviços de gestão de resíduos sólidos urbanos observadas de 2011 a 2015, estima-se uma função de custos multi-produto translog. O índice de economias de gama é de -0.27, significando que existem deseconomias de gama

Triaqua­bis{μ-N-[N-(4-meth­oxy-2-oxidobenzyl­idene)glyc­yl]glycinato(3−)}cadmium(II)dicopper(II) dihydrate

In the title compound, [CdCu2(C12H11N2O5)2(H2O)3]·2H2O, the CuII atoms are in a square plane of N2O2 atoms contributed by the tetra­dentate Schiff base trianion. The CuII atoms are coordinated by one phenolate O atom, one imine N atom, one amido N atom and one carboxyl­ate O atom. The CdII atom is connected via the carboxyl­ate groups, forming a heterotrinuclear CuII–CdII–CuII system. The CdII atom is seven-coordinate in a penta­gonal-bipyramidal geometry with four O atoms from two carboxyl­ate groups and three aqua ligands. The heterotrinuclear mol­ecules are linked to the uncoordinated water mol­ecules by O—H⋯O hydrogen bonds into a three-dimensional framework

Hexaaqua­magnesium(II) bis­{[N-(4-meth­oxy-2-oxidobenzyl­idene)glycyl­glycinato(3−)]cuprate(II)} hexa­hydrate

In the title complex, [Mg(H2O)6][Cu(C12H11N2O5)]2·6H2O, the CuII atoms lie at the center of the square plane of triple negatively charged O,N,N′,O′-tetra­dentate Schiff base ligands, which are coordinated by one phenolate O atom, one imine N atom, one deprotonated amide N atom and one carboxyl­ate O atom. The MgII center, which sits on an inversion center, is coordinated by six aqua ligands and exhibits a slightly distorted octa­hedral conformation. The asymmetric unit consists of an [N-(4-meth­oxy-2-oxidobenzyl­idene)glycyl­glycinato]cuprate(II) anion, one half of an [Mg(H2O)6]2+ cation and three free water mol­ecules. The cations and anions form columns by O—H⋯O hydrogen bonds

Integrated dynamic analysis of a spar floating wind turbine with a hydraulic drivetrain

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Hexaaqua­cobalt(II) bis­{[N-(4-meth­oxy-2-oxidobenzyl­idene)glycylglycinato]nickel(II)} hexa­hydrate

In the title compound, [Co(H2O)6][Ni(C12H11N2O5)]2·6H2O, the NiII atom has a nearly square-planar coordination with two N and two O atoms of the N-(4-meth­oxy-2-oxidobenzyl­idene)glycylglycinate Schiff base ligand (L 3−). The CoII atom sits on an inversion center and is coordinated to six aqua ligands in a slightly distorted octa­hedral geometry. The [Co(H2O)6]2+ cations and [NiL]− anions form columns along the a axis by O—H⋯O hydrogen bonds. Additional hydrogen bonds between the uncoordinated and coordinated water molecules help to consolidate the crystal packing

Direct Regularization from Co-Registered Anatomical Images for MRI-Guided Near-Infrared Spectral Tomographic Image Reconstruction

Combining anatomical information from high resolution imaging modalities to guide near-infrared spectral tomography (NIRST) is an efficient strategy for improving the quality of the reconstructed spectral images. A new approach for incorporating image information directly into the inversion matrix regularization was examined using Direct Regularization from Images (DRI), which encodes the gray-scale data into the NIRST image reconstruction problem. This process has the benefit of eliminating user intervention such as image segmentation of distinct regions. Specifically, the Dynamic Contrast Enhanced Magnetic Resonance (DCE-MR) image intensity value differences within the anatomical image were used to implement an exponentially-weighted regularization function between the image pixels. The algorithm was validated using simulated reconstructions with noise, and the results showed that spatial resolution and robustness of the reconstructed images were significantly improved by appropriate choice of the regularization weight parameters. The proposed approach was also tested on in vivo breast data acquired in a recent clinical trial combining NIRST / MRI for cancer tumor characterization. Relative to the standard “no priors” diffuse recovery, the contrast of the tumor to the normal surrounding tissue increased from 2.4 to 3.6, and the difference between the tumor size segmented from DCE-MR images and reconstructed optical images decreased from 18% to 6%, while there was an overall decrease in surface artifacts