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21.
22.
Krzysztof Piasecki Ewa Roszkowska Tomasz Wachowicz Marzena Filipowicz-Chomko Anna yczkowska-Hankowiak 《Entropy (Basel, Switzerland)》2021,23(8)
We consider the negotiation problem, in which an agent negotiates on behalf of a principal. Our considerations are focused on the Inspire negotiation support system in which the principal’s preferences are visualised by circles. In this way, the principal describes the importance of each negotiation issue and the relative utility of each considered option. The paper proposes how this preference information may be implemented by the agent for determining a scoring function used to support decisions throughout the negotiation process. The starting point of our considerations is a discussion regarding the visualisation of the principal’s preferences. We assume here that the importance of each issue and the utility of each option increases with the size of the circle representing them. The imprecise meaning of the notion of “circle size” implies that in a considered case, the utility of an option should be evaluated by a fuzzy number. The proposed utility fuzzification is justified by a simple analysis of results obtained from the empirical prenegotiation experiment. A novel method is proposed to determine trapezoidal fuzzy numbers, which evaluates an option’s utility using a series of answers given by the participants of the experiment. The utilities obtained this way are applied to determine the fuzzy scoring function for an agent. By determining such a common generalised fuzzy scoring system, our approach helps agents handle the differences in human cognitive processes associated with understanding the principal’s preferences. This work is the first approach to fuzzification of the preferences in the Inspire negotiation support system. 相似文献
23.
JPC – Journal of Planar Chromatography – Modern TLC - A new, accurate, rapid TLC method has been established for determination of timolol maleate (Timohexal 0.1%, Timoptic 0.25%) and... 相似文献
24.
Joanna?Dobrzyńska Marzena?D?browska Rafa??Olchowski Ryszard?DobrowolskiEmail authorView authors OrcID profile 《Mikrochimica acta》2018,185(12):564
A gold(III)-imprinted thiocyanato-functionalized silica network of type SBA-15 was prepared by co-condensation of tetraethoxysilane (TEOS) with thiocyanatopropyltriethoxysilane (TCTES) in the presence of Pluronic123 and Au(III) ions. Compared to the non-imprinted material, the imprint has a higher selectivity and adsorption capacity for Au(III). The maximum static adsorption capacity for Au(III) is 475 mg·g?1 for the ion-imprinted, and 62 mg·g?1 for the non-imprinted sorbent. The imprint was applied to the sorption of Au(III) from digested geological samples prior to its determination by graphite furnace atomic absorption spectrometry. Adsorption is fast and does not substantially prolong the analytical procedure. Under optimum conditions, the detection limit for Au(III) is 2 ng·g?1. The method was validated by analyzing certified reference materials, and results were in good agreement with certified values. The procedure was successfully applied to the separation and determination of gold in complex geological samples. 相似文献
25.
Komsta Łukasz Sztanke Krzysztof Mączka Paulina Ucherek Marzena Skibiński Robert Gumieniczek Anna 《平面色谱法杂志一现代薄层色谱法》2009,22(5):327-331
JPC – Journal of Planar Chromatography – Modern TLC - The lipophilicity, log P, of 27 novel imidazo[2,1-c][1,2,4]triazine derivatives with strong biological activity has been determined... 相似文献
26.
Marzena Białek Monika Pochwała Grzegorz Spaleniak 《Journal of polymer science. Part A, Polymer chemistry》2014,52(15):2111-2123
A series of novel titanium(IV) complexes bearing tetradentate [ONNO] salan type ligands: [Ti{2,2′‐(OC6H3‐5‐t‐Bu)2‐NHRNH}Cl2] (Lig1TiCl2: R = C2H4; Lig2TiCl2: R = C4H8; Lig3TiCl2: R = C6H12) and [Ti{2,2′‐(OC6H2‐3,5‐di‐t‐Bu)2‐NHC6H12NH}Cl2] (Lig4TiCl2) were synthesized and used in the (co)polymerization of olefins. Vanadium and zirconium complexes: [ M{2,2′‐(OC6H3‐3,5‐di‐t‐Bu)2‐NHC6H12NH}Cl2] (Lig4VCl2: M = V; Lig4ZrCl2: M = Zr) were also synthesized for comparative investigations. All the complexes turned out active in 1‐octene polymerization after activation by MAO and/or Al(i‐Bu)3/[Ph3C][B(C6F5)4]. The catalytic performance of titanium complexes was strictly dependent on their structures and it improves for the increasing length of the aliphatic linkage between nitrogen atoms (Lig1TiCl2 << Lig2TiCl2 < Lig3TiCl2) and declines after adding additional tert‐Bu group on the aromatic rings (Lig3TiCl2 < Lig4TiCl2). The activity of all titanium complexes in ethylene polymerization was moderate and the properties of polyethylene was dependent on the ligand structure, cocatalyst type, and reaction conditions. The Et2AlCl‐activated complexes gave polymers with lover molecular weights and bimodal distribution, whereas ultra‐high molecular weight PE (up to 3588 kg mol?1) and narrow MWD was formed for MAO as a cocatalyst. Vanadium complex yielded PE with the highest productivity (1925.3 kg molv?1), with high molecular weight (1986 kg mol?1) and with very narrow molecular weight distribution (1.5). Copolymerization tests showed that titanium complexes yielded ethylene/1‐octene copolymers, whereas vanadium catalysts produced product mixtures. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2111–2123 相似文献
27.
Cydzik M Rudowska M Stefanowicz P Szewczuk Z 《Journal of the American Society for Mass Spectrometry》2011,22(12):2103-2107
Derivatization of peptides as quaternary ammonium salts (QAS) is a promising method for sensitive detection by electrospray
ionization tandem mass spectrometry (Cydzik et al. J. Pept. Sci.
2011, 17, 445–453). The peptides derivatized by QAS at their N-termini undergo fragmentation according to the two competing mechanisms –
charge remote (ChR) and charge directed (ChD). The absence of mobile proton in the quaternary salt ion results in ChR dissociation
of a peptide bond. However, Hofmann elimination of quaternary salt creates an ion with one mobile proton leading to the ChD
fragmentation. The experiments on the quaternary ammonium salts with deuterated N-alkyl groups or amide NH bonds revealed
that QAS derivatized peptides dissociate according to the mixed ChR-ChD mechanism. The isotopic labeling allows differentiation
of fragments formed according to ChR and ChD mechanisms. 相似文献
28.
JPC – Journal of Planar Chromatography – Modern TLC - The effects of two-component mobile phases (CCl4-MeOH, CHCl3-MeOH, CH2Cl2-MeOH, and C6H5Cl-MeOH) on the separation of porphyrins by... 相似文献
29.
Jolanta Wawrzyniak Magdalena Rudziska Marzena Gawrysiak-Witulska Krzysztof Przyby 《Molecules (Basel, Switzerland)》2022,27(8)
The need to maintain the highest possible levels of bioactive components contained in raw materials requires the elaboration of tools supporting their processing operations, starting from the first stages of the food production chain. In this study, artificial neural networks (ANNs) and response surface regression (RSR) were used to develop models of phytosterol degradation in bulks of rapeseed stored under various temperatures and water activity conditions (T = 12–30 °C and aw = 0.75–0.90). Among ANNs, networks based on a multilayer perceptron (MLP) and a radial basis function (RBF) were tested. The model input constituted aw, temperature and storage time, whilst the model output was the phytosterol level in seeds. The ANN-based modeling turned out to be more effective in estimating phytosterol levels than the RSR, while MLP-ANNs proved to be more satisfactory than RBF-ANNs. The approximation quality of the ANNs models depended on the number of neurons and the type of activation functions in the hidden layer. The best model was provided by the MLP-ANN containing nine neurons in the hidden layer equipped with the logistic activation function. The model performance evaluation showed its high prediction accuracy and generalization capability (R2 = 0.978; RMSE = 0.140). Its accuracy was also confirmed by the elliptical joint confidence region (EJCR) test. The results show the high usefulness of ANNs in predictive modeling of phytosterol degradation in rapeseeds. The elaborated MLP-ANN model may be used as a support tool in modern postharvest management systems. 相似文献
30.
Phosphorus raw materials are non-renewable, and their resources are shrinking faster and faster as a result of increased fertilizer production. This is due to the increasing population and the need to produce more food. Phosphorus, on the other hand, is one of the main nutrients of plants, without which it is impossible to conduct intensive agricultural production. There are no economically significant phosphate resources in Europe, so they must be imported. That is why it is so important to reduce losses and recover this element from waste streams, which was reflected in the new EU Regulation 2019/1009. A prospective option is to use waste phosphates from the production of polyether polyols. Previous studies show that they contain about 20% phosphorus. Due to their high water content, the most advantageous form of their application is the production of fertilizers in the form of a suspension. The aim of the study is to assess the possibility of using waste phosphates from the production of polyols as raw materials for the production of suspension fertilizers. 相似文献