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121.
Optimization of Multilevel Investments Using Dynamic Programming Based on Fuzzy Cash Flows 总被引:1,自引:0,他引:1
Cengiz Kahraman Da Ruan Cafer Erhan Bozdag 《Fuzzy Optimization and Decision Making》2003,2(2):101-122
Dynamic programming is applicable to any situation where items from several groups must be combined to form an entity, such as a composite investment or a transportation route connecting several districts. The most desirable entity is constructed in stages by forming sub-entities of progressively larger size. At each stage of the development, the sub-entities that are candidates for inclusion in the most desirable entity are retained, and all other sub-entities are discarded. In deterministic dynamic programming, a specification of the current state and current decision is enough to tell us with certainty the new state and costs during the current stage. In many practical problems, these factors may not be known with certainty, even if the current state and decision are known. In this paper, the dynamic programming is applied to the situation where each investment in the set has the following characteristics: the amount to be invested has several possible values, and the rate of return varies with the amount invested. Each sum that may be invested represents a distinct level of investment, and the investment therefore has multiple levels. A fuzzy present worth based dynamic programming approach is used. A numeric example for a multilevel investment with fuzzy geometric cash flows is given. A computer software named FUZDYN is developed for various problems such as alternatives having different lives, different uniform cash flows, and different ranking methods. 相似文献
122.
The one-orbital model for manganites with cooperative phonons and superexchange coupling JAF is investigated via large-scale Monte Carlo simulations. The results for two orbitals are also briefly discussed. Focusing on the electron density n=0.75, a regime of competition between ferromagnetic metallic and charge-ordered (CO) insulating states is identified. In the vicinity of the associated bicritical point, colossal magnetoresistance (CMR) effects are observed. The CMR is associated with the development of short-distance correlations among polarons, above the spin ordering temperatures, resembling the charge arrangement of the low-temperature CO state. 相似文献
123.
Utility of the Pfitzinger Reaction in the Synthesis of Novel Quinoline Derivatives and Related Heterocycles 下载免费PDF全文
Derviş Gök Rahmi Kasımoğulları Mustafa Cengiz Samet Mert 《Journal of heterocyclic chemistry》2014,51(1):224-232
2‐(2‐Amino‐3,5‐dinitrophenyl)‐2‐oxoacetic acid ( 2 ) was obtained from hydrolysis of 5,7‐dinitroisatin ( 1 ) in alkaline media. A novel quinoxaline derivative ( 3 ) was synthesized from the reaction of the same compound ( 1 ) with o‐phenylenediamine. Reacting 2 with ethyl 3‐oxo‐3‐phenylpropanoate yields 6,8‐dinitro‐2‐phenylquinoline‐3,4‐dicarboxylic acid ( 4 ). Then, 4 was converted into new quinoline‐diacylchloride, quinoline‐ester, quinoline‐dicarboxamide, pyridazine, and pyrroledione derivatives ( 5 , 6a , 6b , 6c , 6d , 7a , 7b , 7c , 7d , 8 , 9 , 10a , 10b , 10c , 10d , 11a , 11b , 12 ) with SOCl2, alcohols, amines, and hydrazines, respectively. The structures of synthesized compounds were clarified by 1H NMR, 13C NMR, IR, mass and elemental analysis methods. 相似文献
124.
Cengiz Arıcı Ingrid Svoboda Musa Sarı Orhan Atakol Hartmut Fuess 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(1):31-32
The title compound, [NiZnBr2(C3H7NO)2(C17H16N2O2)], is a heterodinuclear nickel complex. The Ni atom has an irregular octahedral environment involving two O and two N atoms from the bis(salicylidene)-1,3-propanediaminate ligand in the equatorial plane, and two O atoms from the dimethylformamide groups. The Zn—O—Ni, O—Zn—O, Ni—O—Zn and O—Ni—O angles in the bridged plane are 100.1 (2), 79.9 (2), 100.4 (2) and 78.89 (17)°, respectively. The Ni⃛Zn distance is 3.0738 (19) Å. 相似文献
125.
An experimental study exploring colour ranges corresponding to different colour names has been conducted. Available colour terms in Turkish language have been identified and the most frequently known or used colour terms have been attained. Using the Munsell Color System, colour ranges reflecting the colour naming and colour perception of Turkish people, have been constructed for each colour term. The discussion of the findings and observations during the research are also included. 相似文献
126.
127.
Crystal Structure and Thermal Decomposition of Square Planar Ni (II) Complexes with ONS Type Ligands
Sefa Durmuş Cengiz Arıcı Ertan Şahin Ümit Ergun Orhan Atakol 《Journal of chemical crystallography》2010,40(9):788-793
Abstract
Similar square planar complexes in the literature were prepared with ONS type N-(2-mercaptophenyl) salicylaldimine and Ni (II). The fourth coordination alongside the tridentate organic ligand was provided by the amine group. The complexes prepared were characterized with Elemental Analyses, IR Spectroscopy and Thermal Analyses. The molecular structures both of the complexes were also determined with X-ray diffraction. The Ni (II) complex was observed to have a highly distorted square planar structure. The temperature range where the nitrogen containing tridentates ligand left the structure and the corresponding heat changes were compared with those in the literature. The residue after thermal decomposition above 650 °C was found to be NiO. 相似文献128.
Şimşek Nermin Arici Cengiz McKee Michael L. Ülkü Dinçcer Balci Metin 《Structural chemistry》2001,12(3-4):305-311
The electrophilic addition of bromine to dimethyl 7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate 10 at 0 and –60°C led in high yield to the formation of dibromide 11. However, high-temperature bromination of 10 in carbon tetrachloride at 77°C gave four products 12–15, three of them with nonrearranged skeleton. Similarly, bromination of the dibromides 14 and 15 at 77°C yielded the nonrearranged tetrabromides 13 and 16, respectively. The structure of the tetrabromide 13 was solved by single-crystal X-ray analysis. The formation mechanism is discussed and supported by calculations. 相似文献
129.
Cengiz Arici Filiz Ercan Raif Kurtaran Orhan Atakol 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):812-814
In the title compounds, {2,2′‐[2,2‐dimethyl‐1,3‐propanediylbis(nitrilomethylidyne)]diphenolato‐κ4N,N′,O,O′}nickel(II), [Ni(C19H20N2O2)], and {2,2′‐[2,2‐dimethyl‐1,3‐propanediylbis(nitrilomethylidyne)]diphenolato‐κ4N,N′,O,O′}copper(II), [Cu(C19H20N2O2)], the NiII and CuII atoms are coordinated by two iminic N and two phenolic O atoms of the N,N′‐bis(salicylidene)‐2,2‐dimethyl‐1,3‐propanediaminate (SALPD2?, C17H16N2O22?) ligand. The geometry of the coordination sphere is planar in the case of the NiII complex and distorted towards tetrahedral for the CuII complex. Both complexes have a cis configuration imposed by the chelate ligand. The dihedral angles between the N/Ni/O and N/Cu/O coordination planes are 17.20 (6) and 35.13 (7)°, respectively. 相似文献
130.
Ozalp VC 《Analytical and bioanalytical chemistry》2012,402(2):799-804
An interferometry-based method was developed for detection of a small molecule, argininamide. The quantification of argininamide
was demonstrated using aptamers immobilized on silicone oxynitride sensor surface via avidin–biotin binding. The aptamers
formed a thin film over avidin layer corresponding to a thickness of 1.2 nm, consistent with a molecular positioning of multipoint
attachment to the surface. The binding of argininamide did not cause any significant changes in the thickness of the aptamer
film, suggesting that the specific binding did not affect the overall conformation of the aptamer molecules after adaptive
rearrangement of aptamer molecules. However, the binding results in clearly detectable changes in mass calculated from multiple
parameters determined by mass deposition and structural changes. The limit of detection of the developed sensor was determined
to be 5 μM. The sensor can monitor real-time changes in argininamide concentrations with high reliability and sensitivity.
The model system demonstrated that a combined measurement considering structural and mass changes through interferometry-based
techniques can overcome one of the major problems associated with real-time monitoring of small mass analytes. 相似文献