Physical Sciences and Mathematics Commons^™

A Variable Gain Pi Controller Used For Speed Control Of A Direct Torque Neuro Fuzzy Controlled Induction Machine Drive, A. Miloudi, Eid A. Al-Radadi, Azeddine Draou

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an original variable gain PI (VGPI) controller for speed control of a direct torque neuro fuzzy controlled (DTNFC) induction motor drive. First, a VGPI speed controller is designed to replace the classical PI controller in a conventional direct torque controlled induction motor drive. Its simulated performances are then compared to those of a classical PI controller. Then, a direct torque neuro fuzzy control (DTNFC) for a voltage source PWM inverter fed induction motor drive is presented. This control scheme uses the stator flux amplitude and the electromagnetic torque errors through an adaptive NF inference system (ANFIS) to …

Using Angle Of Arrival (Bearing) Information For Localization In Robot Networks, Tolga Eren

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we consider using angle of arrival information (bearing) for localization in robot networks. The essential property we require in this paper is that a node can infer heading information from its neighbors. We address the uniqueness of network localization solutions by the theory of globally rigid graphs. We show that while the parallel rigidity problem for formations with bearings is isomorphic to the distance case, the global rigidity of the formation is simpler (in fact identical to the simpler rigidity case) for a network with bearings, compared to formations with distances. We provide the conditions of localization …

Swarm Robot Systems Based On The Evolution Of Personality Traits, Sidney Nascimento Givigi Jr.

Turkish Journal of Electrical Engineering and Computer Sciences

Game theory may be very useful in modeling and analyzing swarms of robots. Using game theory in conjunction with traits of personalities, we achieve intelligent swarm robots. Traits of personality are characteristics of each robot that define the robots' behaviours. The environment is represented as a game and due to the evolution of the traits through a learning process, we show how the robots may react intelligently to changes in the environment. A proof of convergence for the proposed algorithm is offered. The process of selection of traits is discussed and the potential of the modeling is demonstrated in several …

Swarms In Biology And Engineering, Kevin M. Passino

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.

Optimal Location For Shunt Connected Facts Devices In A Series Compensated Long Transmission Line, P.R. Sharma, Ashok Kumar, Narender Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

Shunt FACTS devices are used for controlling transmission voltage, power flow, reducing reactive losses, and damping of power system oscillations for high power transfer levels. In this paper the optimal location of a shunt FACT device is investigated for an actual line model of a transmission line having series compensation at the center. Effect of change in degree of series compensation on the optimal location of the shunt FACTS device to get the highest possible benefit is studied. It is found that the optimal location of the shunt FACTS device varies with the change in the level of series compensation …

A Novel Method For Load Flow Analysis Of Unbalanced Three-Phase Radial Distribution Networks, Masoud Aliakbar Golkar

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel method for load flow analysis in radially operated 3-phase distribution networks without solving the well-known conventional load flow equations. The method can be applied for distribution systems in which the loads are unbalanced. As the size of matrix used is very small compared to those in conventional methods, the amount of memory used is very small, the speed is very high, and the relative speed of calculation increases with the size of the system. The method was applied to some practical networks and the results show the superiority of this method over the conventional ones. …

Direct Code Access In Self-Organizing Neural Networks For Reinforcement Learning, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

TD-FALCON is a self-organizing neural network that incorporates Temporal Difference (TD) methods for reinforcement learning. Despite the advantages of fast and stable learning, TD-FALCON still relies on an iterative process to evaluate each available action in a decision cycle. To remove this deficiency, this paper presents a direct code access procedure whereby TD-FALCON conducts instantaneous searches for cognitive nodes that match with the current states and at the same time provide maximal reward values. Our comparative experiments show that TD-FALCON with direct code access produces comparable performance with the original TD-FALCON while improving significantly in computation efficiency and network complexity.

The Philosophy Of Special Relativity: A Comparison Between Indian And Western Interpretations, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The Western philosophical phenomenalism could be treated as a kind of philosophical basis of the special theory of relativity. The perceptual limitations of our senses hold the key to the understanding of relativistic postulates. The specialness of the speed of light in our phenomenal space and time is more a matter of our perceptual apparatus, than an input postulate to the special theory of relativity. The author believes that the parallels among the phenomenological, Western spiritual and the Eastern Advaita interpretations of special relativity point to an exciting possibility of unifying the Eastern and Western schools of thought to some …

Editors' Introduction: Ecra Vol. 6, No. 4, Patrick Y. K. Chau, Robert J. Kauffman, Norman M. Sadeh, J. Christopher Westland

Research Collection School Of Computing and Information Systems

This issue features a total of 13 articles. The first four articles are part of a special section on “Intelligent agents in e-services”, edited by Professors William K. Cheung and Jane Y. Hsu under the supervision of Professor Robert J. Kauffman. Summaries of articles appearing in the special section are provided in the guest editors’ introduction. The following is a summary of the nine regular submission articles also published in this issue. The review of these articles was kindly coordinated by Professor Jae Kyu Lee, former Editor in Chief of ECRA.

The general submission articles in this issue focus on …

A Philosophical Examination Of Proofs In Mathematics, Eric Almeida

Undergraduate Review

No abstract provided.

Unwired: Student Use Of Technology In The Ubiquitous Computing World, Mike Degagne

Undergraduate Review

No abstract provided.

Intimacy And Face-To-Face Versus Computer Interaction, Emily Snow

Undergraduate Review

No abstract provided.

The E.P.R. Paradox, George Levesque

Undergraduate Review

No abstract provided.

Surge Of Green: A Sustainable Approach To Conductive Polymers, Bethany Masten

Undergraduate Review

No abstract provided.

Bianchi Identities And Weak Gravitational Lensing, Brian Keith

Undergraduate Review

No abstract provided.

Towards Efficient Computation Of Quality Bounded Solutions In Pomdps: Expected Value Approximation And Dynamic Disjunctive Beliefs, Pradeep Reddy Varakantham, Rajiv Maheswaran, Tapana Gupta, Milind Tambe

Research Collection School Of Computing and Information Systems

While POMDPs (partially observable markov decision problems) are a popular computational model with wide-ranging applications, the computational cost for optimal policy generation is prohibitive. Researchers are investigating ever-more efficient algorithms, yet many applications demand such algorithms bound any loss in policy quality when chasing efficiency. To address this challenge, we present two new techniques. The first approximates in the value space to obtain solutions efficiently for a pre-specified error bound. Unlike existing techniques, our technique guarantees the resulting policy will meet this bound. Furthermore, it does not require costly computations to determine the quality loss of the policy. Our second …

Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao

Turkish Journal of Chemistry

Plasma-initiated polymerization of (2-methacryloyloxyethyl) thrimethyl ammonium chloride (MTAC)) was studied. The effects of discharge time and discharge power on temperature in a tubular-type reactor chamber were accurately tested by on-line thermocouple, and the equation relating discharge time, discharge power and temperature in the tubular-type reactor chamber was derived. The results indicated that temperature played a very important role in controlling the solubility of Poly(MTAC) in water. For T \ge 130°, Poly(MTAC) was cross-linked, and the highest rate of absorbing water of Poly(MTAC) was 15 g · g^{-1}. For T < 130°, Poly(MTAC) was linear, and the highest intrinsic viscosity of Poly(MTAC) was 420.2 cm^3 · g^{-1}. The polymerization condition of linear Poly(MTAC) was optimized as follows: discharge time 60 s and discharge power 60 W.

Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari

Turkish Journal of Chemistry

Experimental and theoretical investigations were carried out on 2 sets of chalcones. Set 1 has an OH group on ring A and Set 2 does not, and both have different substituents on ring B at different positions. The experimental investigations comprised cyclic voltammetric (CV) studies to determine the reactivity in terms of redox potentials in DMF at room temperature (23 \pm 1 °C). Electrochemical parameters from cyclic voltammograms were used to evaluate the reversibility of electron transfer, standard reduction potentials, solvation energies, electron affinities, diffusion coefficients, critical scan rates and heterogeneous electron transfer rate constants. Heterogeneous electron transfer rate constants …

Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu

Turkish Journal of Chemistry

Chloro organotin(IV) dipyrazolinates of the type RSnCl(C_{15}H_{12}N_2OX)_2 [where C_{15}H_{12}N_2OX = 3(2'-Hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X = H (a); CH_3 (b); OCH_3 (c); Cl (d) and R = Me, Pr^n and Ph] were synthesised by the reaction of RSnCl_3 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesised derivatives were characterised by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement and spectral [IR and multinuclear NMR (^1H, ^{13}C and ^{119}Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, ^1H and ^{13}C NMR spectral data. An octahedral structure around the tin(IV) …

Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu

Turkish Journal of Chemistry

Oligo-2-[(2-hydroxymethylphenylimino) methyl] phenol O-(2-HMPIMP) and oligo-2-[(2-hydroxymet\-hylphenyl imino) methyl]-5-bromo-phenol O-(2-HMPIMBP) were synthesized by the oxidative polycondensation reaction using air as an oxidant in an aqueous alkaline medium at 70 °C. They were characterized by ^1H-NMR, FT-IR, UV-vis, TG, size exclusion chromatography (SEC) and elemental analysis. According to the SEC analyses, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of O-2-HMPIMBP and O-2-HMPIMP are 1100, 1600 g mol^{-1} and 1.45; and 6000, 6250 g mol^{-1} and 1.04, respectively. According to TG analyses, the weight losses of O-2-HMPIMP and O-2-HMPIMBP are 98.31% and 96.91%, respectively, at 900 …

New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide and azobenzene moieties in the main chain was synthesized by the solution polycondensation reaction of 4,4`-azodibenzoic acid with bis(3-aminophenyl) phenyl phosphine oxide using thionyl chloride, N-methyl-2-pyrrolidone and pyridine. This new polymer was obtained in high yield (96%) and showed high inherent viscosity (0.55 dL/g) and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG) and solubility test. Furthermore, another polyamide was prepared by solution polycondensation reaction of 4,4`-azodibenzoic acid with 1,4-phenylene diamine and its flame-retardant behavior was compared by the use of the LOI with the previous one.

Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi

Turkish Journal of Chemistry

Alcohols and phenols were tetrahydropyranylated in the presence of 2,4,6-trichloro[1,3,5]triazine in good to excellent yields in acetonitrile.

A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami

Turkish Journal of Chemistry

A quick and convenient method for the preparation of 2-aminobenzophenone derivatives is described. This approach consists of the nucleophilic substitution reaction of nitrobenzenes by phenylacetonitrile under conventional and ultrasonic conditions followed by reduction of the produced 2,1-benzisoxazole to 2-aminobenzophenone. This 2-step reaction was studied by changing the reaction parameters (reaction temperature, ultrasound power, and reaction time). The results clearly demonstrated that using ultrasound irradiation results in a high yield within a short reaction time.

Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin

Turkish Journal of Chemistry

Isomerisation of nC_7 over a sulphated zirconia (SZ)-based bifunctional catalyst was studied at 150 °C. Au, Ir, Pd and Pt were used as promoters of SZ. The first objective was the production of C_7 isomers with high octane numbers. PtSZ is the most suitable catalyst despite low conversions and a high proportion of methylhexanes instead of dimethylpentanes. The second objective was to assess Au as a promoter of SZ. Au shows slight hydrogenation abilities, displaying behaviour similar to that of Pd, but is inactive towards alkane activation. These promising but inadequate results suggested that Au could be used as the …

Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya

Turkish Journal of Chemistry

This paper presents the synthesis and characterization of polyimides containing a chiral (R,R) or (S,S) 1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone. The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol- 2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material.

Synthesis Of 2-Acylamino, 2-Aroylamino And Ethoxycarbonyl Imino-1,3,4-Thiadiazoles As Antitumor Agents, Kemal Sancak, Yasemi̇n Ünver, Mustafa Er

Turkish Journal of Chemistry

2-Amino-1,3,4-thiadiazoles compounds (2a-e) were obtained from the reaction of thiosemi carbazide with 2-cyanomethoxyphenoxyacetonitriles (1). Mono acylamino, mono aroylamino and diethoxycarbonyl imino-1,3,4-thiadiazole compounds (3a-e, 4a-e, 5a-c) were synthesized via the reaction of 2-amino-1,3,4-thiadiazole compounds (2a-e) with acetyl chloride or acetic anhydride, benzoyl chloride or benzoic anhydride and ethyl chloroformate, respectively. The in vitro antitumor activities of some selected compounds were screened and compounds 2a, 2b, 2c, 3a, 3b, 3c, 5a, 5b and 5c were found to be active.

Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

The reaction of amidrazones 1 with \alpha-haloesters 2 formed 1,3,5-substituted 4,5-dihydro-1,2,4-triazin-6-ones (4a-z) rather than 1,2,4-triazin-5-one derivatives (5a-z). The microanalysis and spectral data of the synthesized compounds are in full agreement with their molecular structure.

Iridoid Glucosides From Lamium Garganicum Subsp. Laevigatum, Tayfun Ersöz, Duygu Kaya, Funda Nuray Yalçin, Cavi̇t Kazaz, Erhan Palaska, Charlott H. Gotfredsen, Soren R. Jensen, İhsan Çaliş

Turkish Journal of Chemistry

Phytochemical investigations on the above-ground parts of Lamium garganicum subsp. laevigatum resulted in the isolation of 7 iridoid glucosides: shanzhiside methyl ester (1), barlerin (8-O-acetylshanzhiside methyl ester) (2), 6-O-syringyl-8-O-acetylshanzhiside methyl ester (3), 6\beta-hydroxyipolamiide (4), lamalbide (5), dehydropenstemoside (6), and sesamoside (7). The structure of the iridoids was elucidated by spectroscopic (UV, IR, 1D- and 2D-NMR, and ESI-MS) evidence.

Investigation Of Some 1,3-Diols For The Requirements Of Solvent Extraction Of Boron: 2,2,6-Trimethyl-1,3 Heptanediol As A Potential Boron Extractant, Bi̇lsen Tural, Servet Tural, Hali̇l Hoşgören

Turkish Journal of Chemistry

Eighteen 1,3-diols were synthesized and their structure and distribution ratio for the solvent extraction of boron were studied. Diols with a high distribution ratio (D_{B(OH)_3 > 10) were investigated for the requirements of solvent extraction of boron. Their extraction capacity, and solubility in aqueous phase and in organic diluents were investigated by comparison to 2-ethyl-1,3-hexanediol (EHD), which is widely used as a boron extractant. Among a series of 1,3 diols, 1-benzyl-2,2-dimethyl-1,3-propanediol (4a) and 2,2,6-trimethyl-1,3-heptanediol (3a) were found to have very low solubility in the aqueous phase compared to the others. IPD (3a) was found to have a high solubility in aliphatic …

Investigation Of The Voltammetric Characteristics Of Poly(1,4-Diaminobenzene) Film As A Dopamine-Selective Polymer Electrode, Gamze Erdoğdu, A. Ersi̇n Karagözler

Turkish Journal of Chemistry

Electrochemical polymerization of 1,4-diaminobenzene in the KCl aqueous electrolyte at a potential of 0.600 V versus Ag/AgCl produces adherent poly(1,4-diaminobenzene) film on a gold electrode. The electrochemical behavior of dopamine and ascorbic acid at the polymer electrode prepared in this manner was examined by cyclic and differential pulse voltammetry. Voltammetry studies showed that polymeric film with a thickness corresponding to a 7-mC charge exhibited selective permeation for dopamine while retaining ascorbic acid. All the polymerization parameters affecting the permselective characteristics were systematically investigated and the optimum values were determined. The results showed that a polymeric membrane, owing to its permselective …