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31.
The idea of non-hierarchical production networks consisting of autonomous enterprises has been present in scientific community for more than 20 years. Although some global corporations are using their own production networks across continents, they are not similar to the original idea of non-hierarchical production networks in many aspects. It seems that this idea waited for production systems to acquire proper information and communications technology (ICT) or new industrial platforms, like Industry 4.0. The result is a new type of production network called Cyber-Physical Production Network (CPPN). The CPPN is, from ICT point of view, ready to act as non-hierarchical production networks consisting of autonomous production systems with many automated processes. One of the most important processes of the CPPN is a selection of optimal partners (enterprises) to be part of a new virtual enterprise, created inside production network. An optimisation problem emerges in this process, and it is called Partner Selection Problem (PSP). It is non-polynomial-hard combinatorial problem. Since metaheuristic algorithms are well-proven in solving that kind of problem, a specially designed metaheuristic algorithm derived from ant colony optimisation and named the HUMANT (HUManoid ANT) algorithm is used in this paper. It is multi-objective optimisation algorithm that successfully solves different instances of PSP with two, three, four or more objectives. 相似文献
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33.
Marko Jovanovi? Richard Tyldesley-Worster Gottfried Pohlentz Jasna Peter-Katalini? 《International journal of molecular sciences》2014,15(4):6527-6543
Human milk oligosaccharides (HMO) represent the bioactive components of human milk, influencing the infant’s gastrointestinal microflora and immune system. Structurally, they represent a highly complex class of analyte, where the main core oligosaccharide structures are built from galactose and N-acetylglucosamine, linked by 1–3 or 1–4 glycosidic linkages and potentially modified with fucose and sialic acid residues. The core structures can be linear or branched. Additional structural complexity in samples can be induced by endogenous exoglycosidase activity or chemical procedures during the sample preparation. Here, we show that using matrix-assisted laser desorption/ionization (MALDI) quadrupole-time-of-flight (Q-TOF) collision-induced dissociation (CID) as a fast screening method, diagnostic structural information about single oligosaccharide components present in a complex mixture can be obtained. According to sequencing data on 14 out of 22 parent ions detected in a single high molecular weight oligosaccharide chromatographic fraction, 20 different oligosaccharide structure types, corresponding to over 30 isomeric oligosaccharide structures and over 100 possible HMO isomers when biosynthetic linkage variations were taken into account, were postulated. For MS/MS data analysis, we used the de novo sequencing approach using diagnostic ion analysis on reduced oligosaccharides by following known biosynthetic rules. Using this approach, de novo characterization has been achieved also for the structures, which could not have been predicted. 相似文献
34.
Maikel Kishna Simona Negro Floortje Alkemade Marko Hekkert 《Industry and innovation》2017,24(3):263-279
This paper focuses on the strategies of incumbents that seek to develop discontinuous innovations within the boundaries of a mature innovation system. Mature innovation systems do not provide support for these discontinuous innovations. This article focuses on exploring why incumbents in these setting engage in discontinuous innovation and what strategies they deploy to become successful. We analyse 10 cases of incumbents developing discontinuous innovations in the mature Dutch greenhouse horticulture sector. The results of our analysis show that the incumbents are primarily triggered by dissatisfaction with the current way of doing business and that the existing institutions are the main barrier to discontinuous innovation. In response, the incumbents try to circumvent the existing innovation system in their innovation process, but when successful also engage in changing the existing innovation system. This paper contributes to the understanding of the role of incumbents as source of discontinuous innovation in mature innovation systems. 相似文献
35.
Experimental results show that the application of standard methods of reconditioning components of titanium alloys reduces the mechanical properties of welded joints by up to 30%. The main reasons for this are structural changes and weld defects. The modified (La, Y and B) filler materials were developed from titanium alloys with a submicrocrystalline structure. These materials produce the equiaxed and ductile structures in welded joints in titanium alloys so that the mechanical properties of the welded joints equal 0.9 of the properties of the parent metal. Consequently, the range of repairs of rotors of gas turbine engines can be greatly widened. 相似文献
36.
Anita Valmarska Dragana Miljkovic Nada Lavrač Marko Robnik-Šikonja 《Journal of Intelligent Information Systems》2018,51(2):301-337
Parkinson’s disease is a neurodegenerative disorder that affects people worldwide. Careful management of patient’s condition is crucial to ensure the patient’s independence and quality of life. This is achieved by personalized treatment based on individual patient’s symptoms and medical history. The aim of this study is to determine patient groups with similar disease progression patterns coupled with patterns of medications change that lead to the improvement or decline of patients’ quality of life symptoms. To this end, this paper proposes a new methodology for clustering of short time series of patients’ symptoms and prescribed medications data, and time sequence data analysis using skip-grams to monitor disease progression. The results demonstrate that motor and autonomic symptoms are the most informative for evaluating the quality of life of Parkinson’s disease patients. We show that Parkinson’s disease patients can be divided into clusters ordered in accordance with the severity of their symptoms. By following the evolution of symptoms for each patient separately, we were able to determine patterns of medications change which can lead to the improvement or worsening of the patients’ quality of life. 相似文献
37.
In this article, the role of the restoring stiffness, as one of the basic parameters in ship hydroelastic analysis, is brought
out. It is formulated using the variational principle and the method of virtual displacements. It is shown that asymmetry
of the restoring stiffness is a physical reality. Moreover, it is confirmed that modal variation, still disputed in the relevant
literature, has to be taken into account to satisfy the ship’s stability. Consistent stiffness is formulated here by regarding
stiffness definition as relation between forces and displacements. Hybrid stiffness known from the literature is wrong since
some terms are specified as relation between forces and displacement gradient. Influence of the consistent and symmetrized
stiffness matrix, and the hybrid one, on dynamic response is illustrated for a prismatic pontoon and a large container ship.
It is found that the latter two matrices do not assure convergence of transfer functions of sectional forces to zero value
as the wave frequency approaches zero. The rigid body and elastic responses are compared, and pertinent conclusions are drawn.
It is also shown that it is not necessary to use the unified geometric and restoring stiffness for ordinary hydroelastic analysis
of ship structures. The consistent formulation of the restoring stiffness matrix will be useful for extending linear potential
theory hydrodynamic codes for rigid body analysis to deformable bodies. 相似文献
38.
39.
Dr. Andrija Smelcerovic Dr. Jelena Lazarevic Katarina Tomovic Marija Anastasijevic Dr. Marko Jukic Dr. Gordana Kocic Dr. Marko Anderluh 《ChemMedChem》2019,14(5):514-521
Due to uncomfortable injection regimens of peptidic agonists of glucagon-like peptide-1 receptor (GLP-1R), orally available nonpeptide positive allosteric modulators (PAMs) of GLP-1Rs are foreseen as the possible future mainstream therapy for type 2 diabetes. Herein, current GLP-1R PAMs are reviewed. Based on the effectiveness and in silico predicted physicochemical properties, pharmacokinetics, and toxicity, possible candidates for further development as oral drugs were selected. The suggestion is that GLP-1R PAMs might be used orally alone or in combination with dipeptidyl peptidase-4 (DPP-4) inhibitors, which could offer an optimal treatment option next to metformin monotherapy in type 2 diabetes mellitus, or in a wider spectrum of indications. Quercetin acts as a GLP-1R PAM and DPP-4 inhibitor, and therefore, might be considered as a pioneering agent with a dual mechanism of action, in terms of GLP-1R positive allosteric modulation and DPP-4 inhibition for potentiating GLP-1 dependent effects. 相似文献
40.
An increasing requisite regarding the reproduction quality of electrophotographic printing machines demands improvement of new electrophotographic toner formulation, especially used pigments. The subject of this paper is a comparison of prints realised by depositing high chroma (HC) and standard emulsion aggregation (EA) toner on gloss fine art paper. HC toner has a different composition of the cyan and magenta tones compared with the corresponding standard EA toner tones and therefore behaves differently under real conditions. The patches used for this experiment were cyan and magenta tone prints with tone values (TVs) of 0, 20, 60 and 100%. Ultraviolet (UV) degradation was measured over time intervals of 0, 6, 12, 24, 48, 96, 144 and 240 h for all patches. Results (laboratory values) were calculated using colorimetric difference. Values were plotted as a function of time in tonal degradation graphs. A model was created using non‐linear regression‐based modelling. The experiment demonstrates that magenta patches are more susceptible to degradation in comparison with cyan patches. With the increase in tonal value, it is noticeable that the colorimetric difference is higher. Colorimetric differences calculated using HC magenta toner and standard EA cyan toner (100% TV) were higher than ?E = 5, starting to appear after 6 h of exposure to UV radiance. After 12 h of exposure, colorimetric differences of standard magenta tones that were greater than ?E = 5 also started to appear. Cyan patches (100% TV) printed with HC toner were more stable than the other patches, and after 240 h of exposure had not crossed the boundary of ?E = 5. 相似文献