Inverse dynamics of redundant manipulators using a minimum number of control forces

The number of the control actuators used by the inverse kinematics and dynamics algorithms that have been developed in the literature for generating redundant robot joint trajectories is equal to the number of the degrees of freedom of the manipulator. In this article, an inverse dynamics algorithm that performs the tasks using only a minimum number of actuators is proposed. The number of actuators is equal to the dimension of the task space, and the control forces are solved simultaneously with the corresponding system motion. It is shown that because all degrees of freedom are not actuated, the control forces may lose the ability to make an instantaneous effect on the end-effector acceleration at certain configurations, yielding the dynamical equation set of the system to be singular. The dynamical equations are modified in the neighborhood of the singular configurations by utilizing higher-order derivative information, so that the singularities in the numerical procedure are avoided. Asymptotically stable inverse dynamics closed-loop control in the presence of perturbations is also discussed. The algorithm is further generalized to closed chain manipulators. Three-link and two-link redundant planar manipulators are analyzed to illustrate the validity of the approach. © 2995 John Wiley & Sons, Inc.     

An IS&R system based on Turkish language

This paper reports an IS&R (Information Storage and Retrieval) system which has been developed to process data stored in two-dimensional tables using a well-defined subset of the Turkish Language. The language referred to as TURDIL is defined by a Regular grammar and is used on an interactive basis. The system has a fully integrated data dictionary which contains table definitions and views of tables, along with information on data-access privileges.     

Interactions between milk proteins and polyphenols: Binding mechanisms,related changes,and the future trends in the dairy industry

The biological activity and techno-functional properties of phenolic compounds have gained great importance due to the epidemiologically-proved health benefits. Use of polyphenols as fortification agents for functional food production and nanotechnological approaches using natural vehicles for polyphenol delivery have been recently discussed. In this respect, milk proteins and dairy products represent unique characteristics for polyphenol studies. The conflicting results on the functionality of polyphenols interacting with milk proteins either in model systems or in complex dairy matrices reveal the need for future studies.     

Determination of polyphenolic constituents and biological activities of bark extracts from different Pinus species

BACKGROUND: The most common commercially available pine bark extract is Pycnogenol^®, a standardised extract of Pinus maritima, which has been reported to have cardiovascular benefits and enhance microcirculation. The present study was conducted to determine the chemical composition of four pine bark extracts, assess their biological activities and to compare the results with Pycnogenol^®. RESULTS: The Pinus species were analysed by LC and LC‐MS; extracts of P. brutia and P. nigra showed higher levels of phenolic constituents compared to P. sylvestris and P. pinea. In particular, P. brutia contained extremely high concentrations of taxifolin (18.5%). The highest radical scavenging activities were attained with P. pinea (88.6%), P. nigra (87.2%) and P. brutia (86.4%) bark extracts. Additionally, anticarcinogenic effects of the extracts and their kinetics were determined in four cell lines including human prostate (PC‐3, DU 145, LNCaP) and breast adenocarcinoma (MCF7) by the MTT assay. Cell viability was reduced to 40% by extracts of P. pinea, and P. sylvestris in PC‐3 cells showing a similar effect like the positive control, CPT‐11. CONCLUSION: Pinus species other than P. maritima definitively possess high biological activities, and therefore present a huge potential to be utilised in the food and the pharmaceutical industries. Copyright © 2009 Society of Chemical Industry     

Seasonal Variations in Fatty Acid Composition of Different Tissues of Mirror Carp,Cyprinus Carpio,in Orenler Dam Lake,Afyonkarahisar, Turkey

The seasonal variations of fatty acids compositions in the muscle, liver, and ovarian tissues of mirror carp (Cyprinus carpio) living in Örenler Dam Lake were determined by using gas chromatography. The results obtained were subjected to statistical analyses by employing SPSS software and p < 0.05 was accepted as significant value. In the statistical analyses, multiple comparisons tests were performed. The results showed that monounsaturated fatty acids levels were found to be higher than that of polyunsaturated fatty acids and saturated fatty acids in all seasons. Palmitic and stearic acid levels were the highest in ovaries (19.95% in winter and 7.79% in summer, respectively). Oleic and palmitoleic levels were at the highest levels in liver tissues (34.53% in summer and 18.37% in winter, respectively). Docosahexaenoic (C22:6ω3, DHA), eicosapentaenoic (C20:5ω3, EPA), eicosatrienoic acid, and arachidonic (C20:4ω6, AA) levels were at the highest level as 17.27, 2.54, and 8.41% in ovaries in the winter and 6.37% in muscle tissues in the spring, respectively. ω3/ω6 ratios were 0.62–0.98 in muscle, 1.54–2.82 in the liver, and 2.82–3.89 in the ovaries. From the point of total fatty acid variations, the highest variations were observed as follows: muscle in spring (26.73%), liver in winter (33.85%), and ovaries in winter 36.38%.     

Apricot Nectar Processing by Pulsed Electric Fields

Application of pulsed electric fields to process apricot nectar by determining the pH, °Brix, total acidity, conductivity, color, non-enzymatic browning index, concentration of mineral ions, and retention of ascorbic acid and beta carotene as well as inactivation of Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, Pseudomonas syringae subs. syringae, Erwinia carotowora, Penicillum expansum, and Botrytis cinerea was explored in this study. Processing of apricot nectar did not cause a significant difference in measured attributes (p > 0.05). However, inactivation of all microorganisms was significantly increased with increased electric field strength and treatment time (p ≤ 0.05). Microbial inactivation data fit both the Weibull distribution and log-logistic model.     

Evaluation of the shifting of the line of sight and higher order aberrations of eyes with keratoconus after corneal cross-linking

Aim

To evaluate changes in the coordinates of the line of sight (LoS) and higher order aberrations (HOAs) of eyes with keratoconus, following corneal cross-linking (CXL).

Optimized method for simultaneous determination of catechin, gallic acid, and methylxanthine compounds in chocolate using RP-HPLC

The simultaneous determination of catechins, gallic acid, and three methylxanthine compounds was determined in chocolate extract by reversed-phase HPLC. An isocratic HPLC procedure using Hypersil-ODS column with methanol three distilled water-formic acid (48.75:200.5:0.75, v/v/v) as a mobile phase was used and the HPLC profiles of 11 chocolate products were obtained. (-)- Epicatechin, (-)-epigallocatechin gallate, levels were very high whereas (+)-catechin, (-)-epigallocatechin and (-)-epicatechin gallate were lower values. Gallic acid was predominant compounds with extremely high levels in all chocolate samples. The content of three methylxanthine, theobromine, theophylline and caffeine was quantified with this procedure. Caffein amounts were low in all samples, while theobromine levels were high in milk and dark chocolates. Theophylline was at trace levels in some chocolates and could not be detected in some samples. This method was reliable, reproducible and objective for quantitative identification of flavanols and alkaloid compounds in the chocolate industry.     

Robust microencapsulated phase change materials in concrete mixes for sustainable buildings

For passive building applications, phase change materials (PCMs) are microencapsulated to avoid leakage of PCM from concrete structure. The primary challenge of using microencapsulated PCM (MPCM) is its weak shell structure. New MPCMs with different shell compositions to prevent breakage during mixing in fresh concrete are needed. In this study, free radical polymerization method to microencapsulate capric acid–myristic acid mixture as PCM with two different methyl methacrylate co‐polymers is proposed to produce robust MPCMs for building applications. Two new microcapsules (MPCM‐1 and MPCM‐2) having latent heats of 91.9 and 97.3 J/g were synthesized. SEM analyses showed the size of microcapsules being in the range of 400–850 nm for MPCM‐1 and 250–475 nm for MPCM‐2. Analyses also reveal that the shells of MPCMs were not harmed, as they were added into concrete mixes. The microsphere's geometry was preserved, and distribution was homogeneous. The MPCMs were also studied under thermal tests of 1000 heating/cooling cycles. No significant changes in thermal properties were observed after thermal cycling tests. Copyright © 2016 John Wiley & Sons, Ltd.