Robust adaptive H∞ control design for heart rate regulation during rhythmic exercises of unknown type

The aim of the study is to regulate the human heart rate (HR) response to a predefined reference profile during aerobic activities of unknown type. A novel feature of the designed control system is obtained to generate the desired rhythmic movements, which is required to achieve the target HR profile during aerobic activities of unknown type. These rhythmic movements or frequency of locomotion is known as the exercise rate (ER) and is quantified as a fundamental measure of exercise intensity. The relationship between ER and HR is modeled by using a linear time‐varying system. The parameters of the model are estimated using a Kalman filter. Based on this model, a robust adaptive H_∞ controller is designed. The H_∞ controller generates target ER (ER_T) corresponding to target HR (HR_T). This ER_T is communicated to the exercising subject by using a human actuating system (HAS). The role of HAS is to achieve ER_T. To validate the performance of the system, it is tested on six healthy subjects during rowing and cycling exercises. The results demonstrate that the designed control system can regulate HR at a given profile with an average root mean square error of 3.1857 bpm and 2.9396 bpm for rowing and cycling, respectively. The developed system can be used for designing an optimal exercising protocol for individuals.     

Thermal,mechanical, and morphological characterization studies of poly(2,6‐dimethyl‐1,4‐phenylene oxide) blends with polystyrene and brominated polystyrene

The miscibility of the binary and ternary blends of poly(2,6‐dimethyl‐1,4‐phenylene oxide), brominated polystyrene, and polystyrene was investigated using a differential scanning calorimeter. The morphology of these blends was characterized by scanning electron microscopy. These studies revealed a close relation between the blend structure and its mechanical properties. The compatibilizing effect of poly(2,6‐dimethyl‐1,4‐phenylene oxide) on the miscibility of the polystyrene/brominated polystyrene blends was examined. It was found that poly(2,6‐dimethyl‐1,4‐phenylene oxide), which was miscible with polystyrene and partially miscible with brominated polystyrene, compatibilizes these two immiscible polymers if its contention exceeds 33 wt %. Upon the addition of poly(2,6‐dimethyl‐1,4‐phenylene oxide) to the immiscible blends of polystyrene/brominated polystyrene, we observed a change in the morphology of the mixtures. An improvement in the mechanical properties was noticed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 225–231, 2000     

Synthesis,characterization, biological activity,and thermal stability of new styrenic polymer having pendant ketone and its some derivatives

A new type of styrene monomer, 1‐{4‐[(4‐vinylbenzyl)oxy]phenyl}ethanone (VBOPE), was synthesized. The oxime, phenylhydrazone, toluol‐4‐sulfonic acid hydrazone, and thiosemicarbazone (TSC) derivatives of VBOPE were prepared with hydroxylamine hydrochloride, phenylhydrazine, toluol‐4‐sulfonic acid hydrazine, and TSC hydrochloride, respectively. Radical homopolymerization of the monomers were prepared at 65°C in 1,4‐dioxane solution with benzoylperoxide as an initiator. The compounds was characterized with Fourier transform infrared and NMR techniques. The thermal properties of polymers were investigated with thermogravimetric analysis and differential scanning calorimetry. The activation energies of the thermal degradation of the polymers were calculated with the Ozawa and Kissinger method. The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

Effects of age on flashbulb memories.

The authors investigated the effect of aging on flashbulb (FB) memories. In 1996, elderly Turks recalled how they had heard about 2 remote events--the death of the first president of Turkey (in 1938) and another event involving a change in the national borders of the country (in 1939)--and both elderly and younger adults recalled how they heard about the recent death of the 8th president of Turkey (in 1993). Seventy percent of the elderly had FB memories for the 1938 death; critical variables for the formation of FB memories were personal importance attached to the event and rehearsal. Ninety percent of younger Turks and 72% of elderly Turks had FB memories for the 1993 death; the only variable that differed between the 2 groups was rehearsal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrocatalytic oxygen reduction and hydrogen evolution reactions on phthalocyanine modified electrodes: Electrochemical, in situ spectroelectrochemical, and in situ electrocolorimetric monitoring

This study describes electrochemical, in situ spectroelectrochemical, and in situ electrocolorimetric monitoring of the electrocatalytic reduction of molecular oxygen and hydronium ion on the phthalocyanine-modified electrodes. For this purpose, electrochemical and in situ spectroelectrochemical characterizations of the metallophthalocyanines (MPc) bearing tetrakis-[4-((4′-trifluoromethyl)phenoxy)phenoxy] groups were performed. While CoPc gives both metal-based and ring-based redox processes, H₂Pc, ZnPc and CuPc show only ring-based electron transfer processes. In situ electrocolorimetric method was applied to investigate the color of the electrogenerated anionic and cationic forms of the complexes. The presence of O₂ in the electrolyte system influences both oxygen reduction reaction and the electrochemical and spectral behaviors of the complexes, which indicate electrocatalytic activity of the complexes for the oxygen reduction reaction. Perchloric acid titrations monitored by voltammetry represent possible electrocatalytic activities of the complexes for hydrogen evolution reaction. CoPc and CuPc coated on a glassy carbon electrode decrease the overpotential of the working electrode for H⁺ reduction. The nature of the metal center changes the electrocatalytic activities for hydrogen evolution reaction in aqueous solution. Although CuPc has an inactive metal center, its electrocatalytic activity is recorded more than CoPc for H⁺ reduction in aqueous solution.     

Profiles of Organic Acid and Volatile Compounds in Acid-Type Cheeses Containing Herbs and Spices (Surk Cheese)

A study was conducted to evaluate the basic chemical composition, organic acids, volatile compound profiles, and overall acceptability of Surk cheese (acid cheese). The organic acids were determined by reverse phase high performance liqued chromatography method, and volatile compounds were analyzed by static headspace/gas chromatography/mass spectrometry technique. A total of 134 volatile compounds, including 42 esters, 40 terpenes, 15 alcohos, 11 free fatty acids, 6 ketones, 5 aldehydes, 4 alkenes, 4 phenyl propanoids, 3 phenolics, and 4 other compounds, were identified in the Surk cheeses. The main compounds were found to be carvacrol, γ-terpinene, p-cymene, hexanoic acid, octanoic acid, decanoic acid, butanoic acid, and eugenol. The mean total organic acid content of the Surk cheese was 1.71 g/100 g. The main organic acid in the Surk cheese was lactic acid (1067 mg/100 g), followed by acetic, propionic, oxalic, formic, citric, pyruvic, orotic, hippuric, and uric acids.     

Inhibition through incremental fragment cuing with primed items.

Completing a word fragment (e.g., r__i__rop) that is revealed gradually (e.g., r__p; r__r__p; r__i__r__p; r__i__rop) was shown to be more difficult than completing the same fragment revealed all at once, but this was true only for words that had been presented beforehand (Peynircio?lu & Watkins, 1986). In the present study a similar inhibitory effect is demonstrated under certain conditions in which words are not presented beforehand. Fragments of words belonging to a newly learned language (Experiment 3) are less likely to be completed when they are revealed gradually than when they are revealed all at once. Thus, priming the test items, whether it be through presentation for study or otherwise, appears to be a significant factor in promoting this inhibitory effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Covert rehearsal of tones.

Z. F. Peynircio?lu and M. L. Palmer (see record 1993-04390-001) found that memory for simple pairs or triples of tones did not benefit from covert rehearsal, although it did benefit from repetition. The present study systematically explored people's ability to rehearse different dimensions and varied the complexity of the musical stimuli. The first 6 experiments showed that even though repetition of tone pairs with pitch or interval as the relevant information led to better long-term recognition, covert rehearsal of the same stimuli did not. The next 2 experiments showed that covert rehearsal of pitch and interval information did benefit immediate recognition, however. The last 2 experiments showed that with more complex musical stimuli covert rehearsal can be effective and can lead to better long-term recognition. The results are discussed within the context of the transfer-appropriate processing framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimentally approved generalized model for circuit applications

In this paper, generalized model based on the multiplicative least square method presented and showed that it is convenient to approximate observation in the electrical system analysis. The introduced model is exponential based and relies on parametric values. The advantage of the method is due to exponential derivation process within multiplicative calculus and has the flexibility to represent widely used functions such as Gaussian and exponentials. In spite of numerous results on the best fitting model, we study the robustness of the method by making direct comparisons with Matlab built‐in functions. The presented model is challenging because modern electrical circuits and systems are faced with different types of inputs that require near exact representation for accurate processing. Some real applications of exponential‐based data were selected to demonstrate the applicability and efficiency of the proposed representation.