An SRWNN-based approach on developing a self-learning and self-evolving adaptive control system for motion platforms

In this paper, a self-recurrent wavelet neural network (SRWNN)-based indirect adaptive control architecture is modified for performing speed control of a motion platform. The transient behaviour of the original learning algorithm has been improved by modifying the learning rate updates. The contribution of the proposed modification has been verified via both simulations and experiments. Moreover, the performance of the proposed architecture is compared with robust RST designs performed on a similar benchmark system, to show that via adaptive nonlinear control, it is possible to obtain a fast step response without degrading the robustness of a multi-body mechanical system. Finally, the architecture is further improved so as to possess structural learning for populating the SRWNNs automatically, rather than employing static network structures, and simulation results are provided to show the performance of the proposed structural learning algorithm.     

Fine needle aspiration biopsy in hepatic Echinococcus multilocularis

OBJECTIVE: To determine the fine needle aspiration biopsy (FNAB) findings in hepatic Echinococcus multilocularis. STUDY DESIGN: FNAB and tru-cut liver needle biopsy were applied in 14 hepatic E multilocularis cases. Cytologic smears were stained with May-Grünwald-Giemsa and periodic acid-Schiff (PAS) stain. Tissue sections were stained with hematoxylin-eosin (HE) and PAS stain. RESULTS: In tissue sections, homogeneous, thin, cystic structures of various dimensions strongly stained with PAS. Mucoid material was stained with PAS in the cystic structures. Wide, coagulative necrosis was observed in all cases. In some cases there were foreign body-type giant cells at the periphery of the lesion. In all the cytologic smears there were an intense necrotic ground, PAS-positive hyaline cuticular structures and mucoid globules; in some cases there were foreign body-type giant cells. CONCLUSION: The above cytologic characteristics are basic diagnostic criteria for FNAB of E multilocularis.     

Composition and thermal properties of cattle fats

The physical‐chemical properties, fatty acid composition and thermal properties of cattle subcutaneous, tallow and intestinal fats were determined. Subcutaneous fat differed from the other fat types with respect to its lower melting point (29.0 °C) and higher saponification (211.4 mg KOH/g) and iodine (50.55) values. The cattle fat types contained palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1n‐9) and linoleic acid (18:2n‐6) as the major components of fatty acid composition (24.58–25.90%, 10.21–33.33%, 28.18–46.05%, 1.54–1.73%, respectively). A differential scanning calorimetry (DSC) study revealed that two characteristic peaks were detected in both crystallization and melting curves. Major peaks (T_peak) of tallow and intestinal fats were similar and determined as 24.10–27.71 °C and 2.16–4.75 °C, respectively, for crystallization peaks and 7.09–9.39 °C and 43.28–46.49 °C, respectively, for melting peaks in DSC curves; however, those of subcutaneous fat (12.48 °C and –6.79 °C for crystallization peaks and 3.56 °C and 23.55 °C for melting peaks) differed remarkably from those of the other fat types.     

Towards a liberalized Turkish natural gas market: a SWOT analysis

Turkey is currently in the process of restructuring and liberalization of its natural gas market. However, Turkish Petroleum Pipeline Corporation’s (BOTAS) monopoly of more than 80% of natural gas imports, and ranging subsidized gas prices from the beginning, mainly for power generators but also for households and the industry, are among the factors preventing the formation of a fully competitive and liberal market. Hence, the primary aim of this study is to gain insight into the private sector view of the restructuring process, through a qualitative inquiry, including an industry-wide survey and a Strengths, Weaknesses, Opportunities, Threats (SWOT) analysis. This study reveals the various internal (Strengths and Weaknesses) and external (Opportunities and Threats) factors, the degree of importance of each factor for the future of the industry, and the level of consistency between these aforementioned assessments. Based on the consensus reached among the Turkish Natural Gas industry representatives, policy recommendations are provided. Results suggest that market liberalization and increase in private sector involvement are the two strengths agreed upon. Likewise, competitive structuring is evaluated as a critical factor for transparency and efficiency, rather than being simply infrastructure-based development. In addition, the participants concur on the importance of increasing share of LNG in the total natural gas supply.     

Synthesis,characterization and dielectric properties of polynorbornadiene–clay nanocomposites by ROMP using intercalated Ruthenium catalyst

Polynorbornadiene clay nanocomposites were prepared for the first time by the ring opening metathesis polymerization (ROMP) using modified montmorillonite and polynorbornadiene the latter of which is used commonly in electric–electronic industry. The Na–MMT clay was modified by a quaternary ammonium salt containing Ruthenium complex as a suitable catalyst and intercalant as well. The norbornadiene monomers were polymerized within the modified montmorillonite layers by in-situ polymerization method in different clay loading degrees. Intercalation ability of the Ru catalyst and partially exfoliated nanocomposite structure were proved by powder X-ray Diffraction (XRD) Spectroscopy and Transmission Electron Microscopy (TEM) methods. The nanocomposite materials with high thermal degradation temperature and low dielectric constant compared to the pure polynorbornadiene were obtained. The dielectric constants decreased with the increase of the clay content.     

Gilbert Damping Constant of Quaternary Co2MnAl1?x Sn x Heusler Alloy Thin Films

Polycrystalline quaternary Co₂MnAl_1?x Sn _x films with x=0.25, 0.5, 0.75,?1 were prepared at room temperature using magnetron sputtering technique on SiO₂ substrates and post-annealed at various temperatures. We investigated the crystal structures, magnetic properties, and magnetic damping constants (??) of the prepared films. Out-of-plane angular dependences of the resonance field and the linewidth of the ferromagnetic resonance spectra were measured and analyzed using the Landau?CLifshitz?CGilbert equation to determine the magnetic properties and damping constant. Co₂MnAl_0.75Sn_0.25 and Co₂MnSn films had A2 ordered crystal structure while Co₂MnAl_0.25Sn_0.75 and Co₂MnAl_0.5Sn_0.5 films had A2 ordering up to 400?°C and 300?°C annealing temperature, respectively, and they had B2 ordering for the remaining temperatures. Also the crystal structure deteriorated at 600?°C for all of the film systems. The saturation magnetization, M _S , of films increased with annealing temperature till 400?°C except Co₂MnAl_0.5Sn_0.5 in which M _S increased till 500?°C, which is consistent with the structural analysis. The effective magnetization was obtained from the FMR spectra and it was found that it decreased with increasing Sn-concentration and reached a minimum value at Co₂MnAl_0.25Sn_0.75 composition. Lastly, Co₂MnAl_1?x Sn _x films annealed at 500?°C showed the best crystal ordering. The lowest ?? value was 0.008 and obtained from Co₂MnAl_0.5Sn_0.5 films annealed at 500?°C.