4,403 research outputs found
Poly[diaqua-μ2-oxalato-di-μ4-succinato-diyttrium(III)]
In the title compound, [Y2(C4H4O4)2(C2O4)(H2O)2]n, the flexible succinate anion assumes a gauche conformation and bridges the eight-coordinated Y atoms, generating two-dimensional layers parallel to (010). The coordination polymer layers are linked into a three-dimensional framework by the rigid oxalate ligands. The oxalate ions are located on a center of inversion. Intermolecular O—H⋯O hydrogen bonds help to stabilize the crystal structure
Hybrid Artificial Bee Colony Algorithm and Particle Swarm Search for Global Optimization
Artificial bee colony (ABC) algorithm is one of the most recent swarm intelligence based algorithms, which has been shown to be competitive to other population-based algorithms. However, there is still an insufficiency in ABC regarding its solution search equation, which is good at exploration but poor at exploitation. To overcome this problem, we propose a novel artificial bee colony algorithm based on particle swarm search mechanism. In this algorithm, for improving the convergence speed, the initial population is generated by using good point set theory rather than random selection firstly. Secondly, in order to enhance the exploitation ability, the employed bee, onlookers, and scouts utilize the mechanism of PSO to search new candidate solutions. Finally, for further improving the searching ability, the chaotic search operator is adopted in the best solution of the current iteration. Our algorithm is tested on some well-known benchmark functions and compared with other algorithms. Results show that our algorithm has good performance
Jakość środowiska, korupcja i rozwój przemysłu: perspektywa globalna
This paper investigates the causal relationship between environmental quality and corruption for 129 countries, using the panel cointegration and panel-based error correction models for the period 2002-2015. In the paper, we use EPI, EHI, and EVI to represent environmental quality, which are more reasonable and comprehensive. We further take industry growth into consideration and investigate its impact on environmental quality. Our results corroborate that there exists a long-term equilibrium cointegrated relationship among the variables, both of corruption and industry growth have a negative effect on environmental quality and the corruption can seriously decrease environmental quality in the long term, while industry growth weakens environmental quality no matter in the short or long run.W artykule zbadano związek przyczynowy między jakością środowiska a korupcją w 129 krajach, wykorzystując modele kointegracji panelowej i panelowej korekcji błędów za lata 2002-2015. W pracy używamy EPI, EHI i EVI do wyznaczania jakości środowiska, które wydają się najbardziej sensowne i wszechstronne. Ponadto bierzemy pod uwagę rozwój branży i badamy jego wpływ na jakość środowiska. Nasze wyniki potwierdzają, że istnieje długoterminowa stabilna skointegorowana relacja pomiędzy zmiennymi, zarówno korupcja, jak i rozwój przemysłu mają negatywny wpływ na jakość środowiska, a korupcja może poważnie obniżyć jakość środowiska w dłuższej perspektywie, podczas gdy wzrost przemysłu osłabia jakość środowiska zarówno w krótkim, jak i długim okresie
(E)-2-(4-Methoxyphenyl)-N-(2-pyridyl)-3-(2-pyridylamino)acrylamide
In the title compound, C20H18N4O2, the aminoacrylamide group makes a dihedral angles of 4.0 (1)° with the amino-bound pyridyl ring and 15.66 (12)° with the amide-bound pyridyl ring. The dihedral angle between the aminoacrylamide group and the pendant 4-methoxyphenyl group is 71.22 (9)°. In the crystal structure, N—H⋯N hydrogen bonds and C—H⋯O and C—H⋯N interactions help to establish the packing. Intramolecular C—H⋯O and C—H⋯(N,O) contacts also occur
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