Paper Type	::	Research Paper
Title	::	Corrosion of Ni-Cr-Mo alloys for fixed dental prostheses in an aqueous solution of 0.05% NaF and in commercial mouthwashes by means of EIS
Country	::	Brazil
Authors	::	N. A. S. Sampaio ||, J. W. J. Silva ||, L. L. Sousa ||, H. A. Acciari ||, E. N. Codaro
Page No.	::	01-11
	::	10.9790/3021-04440111
	::	0.4/3021-04440111
		3021-0404-0411

Ni-Cr-Mo alloys have been used as dental prostheses due their properties such as good mechanical strength, high corrosion resistance and also because they are economically viable. The corrosion protection of these alloys in salt solutions which are typical of physiological media is due to the phenomenon called passivation with an oxide superficial layer formation, particularly chromium oxides. This protective film, subjected to mechanical stress in a corrosive environment, can be broken partially releasing ions that have deleterious effects in a human body. Fluoride ions, existent in hygiene products, change the oral environment and their presence may enable the beginning of a localized corrosion process. The objective of this work is to evaluate the corrosion resistance of three Ni-Cr-Mo alloys, of different compositions: SC (73% Ni, 14% Cr, 8.5% Mo, 1.8% Be, 1.8% Al) SB (61% Ni, 25% Cr, 10.5% Mo, 1.5% Si) and W (65% Ni, 22.5% Cr, 9.5% Mo, 1.0% Nb, 1.0% Si, 0.5% Fe) in media containing fluoride which simulate oral rinse solutions. This study has been performed in solution of 0.05% NaF, NaCl 0.05% and commercial mouthwashes on pH 6.0 at 37°C using metallography analyses, immersion techniques, and electrochemical tests, impedance tests and analysis. SC, with the highest nickel and the lowest chromium content, does not passivate in the studied means showing a continuous increase in current density due to increasing potential, while the other alloys exhibit passivation range of 600 mV and passive current density 10-6 A/cm2. In general, considering the immersion and electrochemical corrosion tests, it is concluded that the worst performance has been attributed to the alloy SC, while W and SB have shown the best performance and very similar behaviors.

 

Keywords: - Ni base alloys, Dental prostheses, Corrosion, Mouthwash.

[1] L.S. Morais, G.S. Guimarães, C.N. Elias, Liberação de íons por biomateriais metálicos. Revista Dental Press de Ortodontia e Ortopedia Facial, Maringá, v.12, n.6, p.48-53, Nov/Dez. 2007.
[2] T. Hanawa, Metal ion release from metal implants, Materials Science and Engineering: C, v. 24, n. 6-8, p. 745-752, Dec. 2004.
[3] N.A. Sampaio, J.W.J. Silva, H.A. Acciari, E.N. Codaro, Corrosion Study of Ni-Cr-Mo Alloys for Fixed Dental Prostheses in an Aqueous Solution of 0.05% NAF and in Commercial Mouthwashes, International Journal of Engineering and Innovative Technology (IJEIT), Volume 2, Issue 12, June 2013. [4] T.R. Figueira, I.C. G. Leite, Oral health perceptions, knowledge and practices among Primary Schoolchildren, RGO, Porto Alegre, v. 56, n.1, p. 27-32, Jan./Mar. 2008. V.S. Saji, H.C. Choe, Electrochemical behavior of Co-Cr and Ni-Cr dental cast alloys, Transactions of nonferrous metals society of China, China, v.19, n.4, p.785-790, Aug. 2009.
[5] M.A. Ameer, E. Khamis, M. Al-Motlaq, Electrochemical behaviour of recasting Ni-Cr and Co-Cr non-precious dental alloys. Corrosion Science, Oxford, v. 46, n. 11, p. 2825-2838, Nov. 2004.

Paper Type	::	Research Paper
Title	::	Multi Level Inverter with Dc Link Switches
Country	::	India
Authors	::	K. Karthik
Page No.	::	12-16
	::	10.9790/3021-04441216
	::	0.4/3021-04441216
		3021-0404-0416

This paper presents a single phase 5 level inverter with dc link Switches using POD technique .The proposed multi level inverter is capable of generating 5 level output with less component count .This technique uses single carrier wave and two sine waves for pulse generation .The entire system is designed and implemented using MATLAB/Simulink .The inverter is connected to a R-load and performance are analysed.

 

Keywords: - 5level inverter, DC link switches, harmonics, R-load , POD technique, less component count, MLI, Electro magnetic interference (EMI)

[1] "Ho-Dong Sun1, Honnyong Cha1, Heung-Geun Kim1, Tae-Won Chun2, Eui-Cheol Nho" "Multi level inverter capable for power factor control with dc link switches "IEEE Trans. Ind. Electron vol.25,pp 400-408, March1991

[2] H. Van der Broeck, "Analysis of the Harmonics in voltage-fed Inverter Drive caused by PWh4 schemes with Discontinuous Switching Operation," EPE '91,Conference Procedings, vol. 3, pp. 261-266, 1991.

[3] J. W. Kolar, H. Ertl, F. C. Zach, "Influence of the Modulation Method on the Conduction and SwitchingLosses of a PWM Converter System," IEEE Trans. On Industry Applications, Vol. 27, no. 6 , pp. 1063 -1075,Nov./Dec. 1991.

[4] Y. Ikeda, J. Itsumi, H. Funato, "The Power Loss of thevoltage-fed Inverter," in Proc. IEEE PESC'88, 1988, pp.

[5] L. K. Mestha, P. D. Evans, "Analysis of on-state losses in PWM Inverters," Proc. IEE-Elect.

Paper Type	::	Review Paper
Title	::	Spectrum Monitoring and management
Country	::	Sudan
Authors	::	Nabil Ali Sharaf Murshed ||, Abdelrasoul jabar Alzubaidi
Page No.	::	17-22
	::	10.9790/3021-04441722
	::	0.4/3021-04441722
		3021-0404-0422

Spectrum Monitoring is, besides Spectrum Planning and Licensing, one of the key elements in spectrum management process. Monitoring is not only solving interference problems but also tasked with for instance:
 Checking license parameters, e.g. field strength and band width (remote inspection)
 Comparing predicted and measured values
 Identifying illegal use
 Supporting preparation for WRC
 Quick overview of the spectrum
 Reframing
Detecting White Spaces, etc Frequency Planning and Licensing provide the theoretical (calculated) occupancy. Monitoring provides the real (automatically or manual measured) occupancy.The smaller the difference between theoretical and real occupancy, the better the quality of the overall spectrum management process.

 

Keywords: Radio spectrum, monitoring station, management, mobile communication, GSM, Digital radio receiver, simulation and design, licensing

[1] Draft Recommendation ITU-R March 2004.
[2] ITU, Handbook Spectrum Monitoring. Edition 2002
[3] Enforcement regulations of an electric wave low, Ministry of Information and Communication Republic of Korea
[4] "Research about method of radio quality measurement" Final Report, Radio Research Laboratory. 1997
[5] Research about reference of radio quality measurement, Electronics and Telecommunications Research Institute, 2001

Paper Type	::	Research Paper
Title	::	K - Domination Number of Butterfly Graphs
Country	::	India
Authors	::	P. Vijaya Jyothi ||, Indrani Kelkar ||, B. Maheswari
Page No.	::	23-27
	::	10.9790/3021-04442327
	::	0.4/3021-04442327
		3021-0404-0427

Butterfly graphs and domination are very important ideas in computer architecture and communication techniques. We present results about one important domination parameter k-domination Number for Butterfly Graph. We find the relation between domination number and k-domination number for BF(n). In this paper we present results about k-domination number of Butterfly Graphs BF(n). We show that domination number and k-domination number of butterfly graphs BF(n) are related to each other as k (BF(n)) > (BF(n)) except for k = 2 and n = 6.

Keywords: Butterfly graph, domination number, k-domination number 2000 Mathematics Subject Classification: 05C69

[1] Barth D. and Raspaud A, Two edge - disjoint Hamiltonian Cycles in the Butterfly Graphs, Information processing letters, 51(1994), 175–179.
[2] Berge C., Theory of graphs and its Applications, Methuen, London, 1962.
[3] Berge C., Graphs and Hypergraphs, North Holland Amsterdam, 1973.
[4] Cockayne E J, Gamble B, Shephard B, An upper bound for k-domination number of a graph, Journal of Graph Theory, 2006, Vol 9 Issue 4, pp 533-534.
[5] Fink J.F., Jacobson M.S., n-Domination in Graphs, in: Alavi Y. and Schwenk A. J.(eds), Graph Theory with Applications to Algorithms and Computer Science, New York, Wiley, 1985, 283–300.

Paper Type	::	Research Paper
Title	::	A Bivariate Generalized Exponential Model for the Effect of Endocrine Responses in Human with Postprandial Distress Syndrome
Country	::	India
Authors	::	S.Lakshmi ||, and N.Durgadevi
Page No.	::	28-33
	::	10.9790/3021-04442833
	::	0.4/3021-04442833
		3021-0404-0433

Suppose a system has two components. Each component is subject to individual independent stress say 𝑈1 and 𝑈2 respectively. The system has an overall stress 𝑈3 which has been transmitted to both the components equally, independent of their individual stresses. Therefore, the observed stress at the two components are 𝑋1=𝑚𝑎𝑥 𝑈1,𝑈3 and 𝑋2=𝑚𝑎𝑥 𝑈2,𝑈3 respectively. If it is assumed that each component has been maintained independently and also there is an overall maintenance. Due to component maintenance, suppose the lifetime of the individual is increased by 𝑈𝑖 amount and because of the overall maintenance, the lifetime of each component is increased by 𝑈3 amount. The study in the Application part is fully characterized the neuroendocrine pathways involved in the gastric response to mental stress in patients with PDS. The increased severity of dyspeptic symptoms induced by acute mental stress in patients with PDS is associated with an enhanced sympathetic output and higher serum levels of stress hormones , ACTH , and cortisol. 𝑰𝒇 𝑋1,𝑋2 ~ 𝐵𝑉𝐺𝐸 𝛼1,𝛼2,𝛼3 , then the joint PDF of 𝑋1,𝑋2 for 𝑥1>0,𝑥2>0, is obtained for the above two variables.

 

Keywords: HPA axis, LF/HF ratio, mental stress, postprandial distress syndrome, CRH, ACTH, cortisol. 2010 AMS Classification: 62HXX, 60EXX.

[1] Arnold, B., (1967) " A note on multivariate distributions with specified marginals", Journal of the American Statistical Association, Vol 62, pp 1460-1461 .
[2] Aro P, Talley NJ., Ronkainen J et al. (2009) Anxiety is associated with Swedish population-based study. Gastroenterology , Vol 137, pp 94-100.
[3] Bremner JD., Bolus R., Mayer EA., (2007) Psychometric properties of the Early Trauma Inventory –Self Report: J Nerv Ment Dis, Vol 195, pp 211- 218.
[4] Chang L., Sundaresh S., Elliott J., (2009) Dysregulation of the hypothalamic pituitary-adrenal (HPA)axis in irritable bowel syndrome: Neurogastroenterol Motil, Vol 21, pp 149-159.
[5] Gupta R D., and Kundu D., (1999) "Generalized exponential distributions" , Australian and New Zealand Journal of statistics, Vol 41, pp 173-188.

Paper Type	::	Research Paper
Title	::	Analysis of used oil on the basis of wear volume using Taguchi method
Country	::	India
Authors	::	Abhay D Kulkani ||, Dr. Geeta Lathkar
Page No.	::	34-40
	::	10.9790/3021-04443440
	::	0.4/3021-04443440
		3021-0404-0440

In heavy forging machines lubricants come under very high contact forces which degrade the lubricant oil .Number of factors are responsible for this degradation they are like ,working temperature, load, speed and environment These are common in hot forging machines. In this present work, new and used lubricant samples evaluated and compared for the wear volume using crossed cylinder test method. Here constant test conditions were a) sliding speed 1.3M/sec and b) temperature 280c .We tested new and used oil samples tested for different parameters like, used hours of oil, sliding distance and) load. Cross cylinder test method was found effective and simple. Here we used the traditional Taguchi's method which optimized test parameters .Results were analysed by the ANOVA and F-tests. Confirmatory tests showed that the results were within the confidence interval.

 

Keywords: - Cross cylinder test, lubricated wears, sliding contact, Taguchi method, oil analysis

[1] Biswajit Bera, Adhessional Friction Law and Adhesive Wear Law of Micromechanical Surface Contact, IJERA, 2(5),2012,404-411
[2] Simon J. Montgomery1, David M. Kennedy1 & Noel O'Dowd, Analysis of wear models for advanced coated materials, Conference on Materials, Tribology, Recycling, Lipanj, Croatia, June 2009,24-26
[3] Alfred Zmitrowicz, Wear patterns and laws of wear-A review, Journal of theoretical and applied,44(2), 2006, 219-253
[4] B. Zhu and G.L. Kelly frictional behaviour and wear performance of a nitrocarburised coating sliding against aisi 1019 steel materials forum ,IMEA,27, 2004 ,54–61
[5] A.W.Ruff and Myshkin, Lubricated Wear Behavior of Composition-Modulated Nickel-Copper Coatings, Journal of Tribology 111 ( 1),2009,111-156

Paper Type	::	Research Paper
Title	::	Steady Flow of Thin Liquid Films on an Inclined Solid surface
Country	::	Iraq
Authors	::	Joseph G. Abdulahad ||, Salih A. Derbaz
Page No.	::	41-46
	::	10.9790/3021-04444146
	::	0.4/3021-04444146
		3021-0404-0446

In this paper, we consider the thinning process of an inclined thin liquid film over a solid boundary with an inclination angle to the horizontal in gravity driven flow. Throughout this work, we assumed that the fluid thickness is constant far behind the front and we neglect the thickness of the film at the beginning of the motion. The differential equation of the film thickness is obtained analytically and the solution of equation that represents the film thickness is obtained numerically by using Rung-Kutta method.

 

Keywords: - Thin Liquid Films , Navier-Stokes equations , continuity equation .

[1] Bertozzi, A.L. (1998). The mathematics of moving contact lines in thin liquid film, Amer. Math. Soc. Pp. 689–697, 45.

[2] Diez, J., Kondic L. and Bertozzi, A.L. (2001). Global models for moving contact lines, Phys. Rev., pp. 011208, 63.

[3] Lin. T. S., Kondic, L. and Filippove, A.(2012). Thin films flowing down inverted Substrated three dimensional flow, Physics of fluids, Vol.24, pp. 1-18.

[4] Karmina, K. A., (2013). Fluid flow and stability analysis in certain thin liquid films. M.Sc. thesis, University of Zakho.

[5] Drofler, F., Rauscher M. and Dietrich S.(2013). Stability of thin liquid films and sessile droplets under confinement, Eur. Phys. J. E.Vol.20, pp. 1-14

Paper Type	::	Research Paper
Title	::	Determining Maximum Load Carrying Capacity of 2-link Mechanical Manipulator Using GA and PSO Algorithms
Country	::	Malaysia
Authors	::	NiushaShafiabady ||, Dino Isa ||, M.A. NimaVakilian
Page No.	::	47-57
	::	10.9790/3021-04444757
	::	0.4/3021-04444757
		3021-0404-0457

This paper presents calculating the maximum load capacity of 2-link mechanical manipulator using evolutionary algorithms, PSO and GA, applied to the system's dynamic model. GA and PSO are two techniques that have received a lot of attention in recent years, owing to their parallel characteristics and their ability in searching for optimal solutions in irregular and high dimensional solution spaces. As a 2-link mechanical manipulator is a system with high dimensionsthat calculating its maximum load carrying capacity is an important issue, PSO and GA can be of great help in determining this capacity easily and efficiently.

 

Keywords: -Particle Swarm Optimization - Genetic Algorithm, manipulator

[1] IEEE transactions on systems, man, and cybernetics, (2000), vol. 24, no. 4.
[2] Meghdari, A., Naderi, D., &Alam, M. R. Neural-network-basedobserver for real-time tipover estimation,Mechatronics,(2005), vol.15, no. 8, 989–1004.
[3] Chiu, C. S., Lian, K. Y., & Wu, T. C. Robust adaptive motion/forcetracking control design for uncertain constrained robot manipulators. Automatica,(2004), vol. 40, no. 12, 2111–2119.
[4] Dudrík, J., High-Frequency Soft-Switching DC-DC Power Converters.Proc.of the II. Internal Scientific Conf.ofthe Faculty of Electrical Engineeringand Informatics, Košice, (2001), pp.45-46.
[5] Bauer P., Duijsen P.J. van, Challengesand Advances in Simulation, PESC (2005), Brazil.