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Application of fuzzy logic approach to structure based compariso of in-parallel planar manipulators
Get PDFPlanar In-parallel Manipulations, which are nothing but multi degree-of-freedom closed kinematic chains can be modelled as fuzzy systems, so that the fuzzy logic can be applied. It is shown that the fuzzy entropy can be utilized to compare numerous distinct chains, with the same number of links and degrees of freedom from the view point of parallelism so that the designer can have an idea, at the conceptual stage of design regarding suitability of chains, from the view point of rigidity, work space and accumulation of joint errors. Spatial chains are also dealt with. Aspect of work space is verified experimentally
Antibacterial Activity of Solanum surattense Burm. F
Get PDFEthanol extracts of Solanum surattense used in traditional medicine for treatmentof various infections. The antibacterial activity detected was against Staphylococcus aureus, Streptococcus sp.; Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysenteriae and Vibrio cholerae. The highest antibacterial activity was observed in 500μg concentration of leaf extracts of all bacteria screened except Shigella dysenteriae. The minimum zone of inhibition observed in 25μg concentration of leaf extract except Pseudomonas aeruginosa and Shigella dysenteriae. These results indicate that the extracts were bacteriostatic at higher concentrations
Recovery of Silver from Waste X-Ray Film by Alkaline Protease from Conidiobolus coronatus
Get PDFThe waste X-ray/ photographic films contain 1.5 - 2 % (w/w) black metallic silver which isrecovered and reused. Around 18-20% of the world's silver needs are supplied by recyclingphotographic waste. Since silver is linked to gelatin in the emulsion layer, it is possible to break thesame and release the silver using proteolytic enzymes. Alkaline protease from Conidioboluscoronatus was investigated for enzymatic hydrolysis of gelatin from waste X-ray films. At the endof the treatment, gelatin layer was completely removed leaving the polyester film clean and silverwas recovered in the hydrolysate, both of which can be reused. Various parameters such as pH,temperature, enzyme concentration, time etc on silver removal from the film were studied. Gelatinhydrolysis was monitored by measuring increase in turbidity in the hydrolysate, which wasaccompanied by release of protein and hydroxyproline. Gelatin layer was stripped completelywithin 6 min with 1.35 U ml-1 of protease at 40°C, pH 10. Rate of gelatin hydrolysis increased withincreased in protease concentration. The enzyme could be effectively reused for four cycles ofgelatin hydrolysis. Silver in hydolysate was around 3.87% (w/w) based on total weight of sludge
Study of Scrap Waste in Kathmandu Valley
Get PDFScrap wastes are the wastes which are the part of the solid waste, segregated andtaken further for reusing and recycling from the mixed waste. This scrap waste iscalled the Kabadi Waste in Nepal. The objective of this study is to identify the scrapwaste material and assess collection and business activity of scrap waste generatedwith in Kathmandu Valley. Direct observations, formal and informal discussion, fieldstudy with questionnaire were used for data acquisition. 33 random samples, out of178 scrap shop were selected for study. During the period of this study waste fromtransfer station was not allowed to collect by outsiders except by the employed personof the municipality. The composition of scrap waste consisted of 32.49% glasses,23.89% papers, 22.65% plastics and others (metals, textile, leather and rubber)20.97%. Among those reusable material consisted of 38.96% and 44.77% wasrecyclable materials; remaining could be either recycled or reused. 41% of scrapwaste collection was done through door to door by cycle hawker. 53% of the scrapwaste was found recycled or reuse in Nepal. Similarly, 45% of scrap dealersprocessed scrap for further recycling. 36% of the Kabadi shop has employed less than10 people for the waste collection. Now, people from lower casts were also foundinvolved in this business. This study clearly indicates the significance of scrap wastewhich is a part of Municipal Solid Waste
Comparison of dielectric barrier discharge in air, nitrogen and argon at atmospheric pressure
Get PDFThis paper reports the results of electrical characterization of dielectric barrier discharge (DBD) generated in air, nitrogen and argon at atmospheric pressure. Polycarbonate plate of thickness 1 mm was used as a dielectric barrier in a specially designed hemispherical-plane electrode system. A nonuniform filamentary type of discharge was observed in air. Introducing nitrogen and argon gas at controlled flow rate of 1-2 liters / minute resulted a more homogeneous discharge at a frequency of 28 kHz of the AC source. The discharge was investigated for two values of electrode gap of 1 mm and 2 mm by varying the applied voltage. The number of current pulse per half cycle and the magnitude of the discharge current were found to be higher in the case of air discharge in comparison to the discharge in nitrogen and argon. The characteristics of the discharge in air in the absence dielectric barrier was also examined and interestingly it was found that in this case the filamentary discharge turned to a glow discharge for specific value of applied voltage and electrode spacing
Assessment of the efficiency of sewage treatment plants: a comparative study between Nagasandra and Mailasandra sewage treatment plants
Get PDFBangalore city hosts two Urban Wastewater Treatment Plants (UWTPs) towards the periphery of Vrishabhavathi valley, located in Nellakedaranahalli village of Nagasandra and Mailasandra Village, Karnataka, India. These plants are designed and constructed with an aim to manage wastewater so as to minimize and/or remove organic matter, solids, nutrients, disease-causing organisms and other pollutants, before it reenters a water body. It was revealed from the performance study that efficiency of the two treatment plants was poor with respect to removal of total dissolved solids in contrast to the removal/reduction in other parameters like total suspended solids, BOD and COD. In Mailasandra STP, TDS, TSS, BOD, and COD removal efficiency was 20.01, 94.51, 94.98 and 76.26 % and respectively, while in Nagasandra STP, TDS, TSS, BOD, and COD removal efficiency was 28.45, 99.0, 97.6 and 91.60 % respectively. The order of reduction efficiency was TDS < COD < TSS < BOD and TDS < COD < BOD < TSS respectively in Mailasandra and Nagasandra STPs. Additionally, the problems associated with the operation and maintenance of wastewater treatment plants is discussed
Remarks on Certain Selected Fixed Point Theorems - II
Get PDFRecent common fixed point theorems due to Kumar et al and Jungck are used to derive two common fixed point theorems for four finite families of mappings in complete and compact metric spaces respectively.
AMS (MOS) Subject Classification(2000) : Primary 54 H 25; Secondary 47 H 10.
Key Words and phrases: Compatible mapping; coincidentally commuting mappings; coincidence point; fixed point; common fixed point.
DOI: 10.3126/kuset.v3i2.2894
Kathmandu University Journal of Science, Engineering and Technology Vol.3, No.2, August 2007, pp 27-3
Thermal Induced Conductance of KOH Etched Silicon Surface
Get PDFAnisotropic KOH etch rate of silicon is found to vary with thermal agitation along withcrystal plane orientation. In this work, experimental results of etch rate is found with theirunusual values of activation energy along different planes. The various sites that an atomcan occupy are not equivalent of their energy; some are more favorable to removal thanothers. In this paper attention is given to demonstrate thermal activation influences thebehavior of etching mechanism as well as surface morphology. Low-voltage contact modeatomic force microscopy (AFM) has been employed to analyze the morphology of theetched silicon surface at relevant temperature. With temperature evolution the width of theforbidden energy gap is going down and hence conductivity is rises
Biochemical assessment of in vitro and in vivo culture of Tylophora indica (Burm. F.) Merr
Get PDFTylophora indica (Burm. F.) Merr is an endangered plant which can be protected from extinction by its large scale production. Nodal segments of healthy plants are used as explants and cultured on MS Basal medium fortified with different growth regulators. Optimum shoot induction conditions from explants were established. In vitro and in vivo phytochemical test were done by using standard methods for chlorophyll, carbohydrates, proteins, lipids and starch. 3mg/l 2, 4 D showed maximum and success full callus production. Shoot initiation started in 7 days and best shoot regeneration reported with 3 mg/ml BAP in Basal medium. Combination of IBA and NAA in concentration 2 and 4 mg/l respectively proved to be best for root initiation. Concentration of chlorophyll, protein, lipid, carbohydrate, and starch in vitro and in vivo culture are investigated
Effect of bath temperature on the chemical bath deposition of PbSe thin films
Get PDFPbSe thin films are prepared by chemical bath deposition technique over microscope glass substrates from an aqueous acidic bath containing lead nitrate and sodium selenate. The influence of bath temperature on the properties of PbSe film is investigated. The X-ray diffraction analysis showed the deposited films were polycrystalline and having the (111) orientation. The surface morphology study revealed that the grains have cubic shape crystal. The band gap energy was decreased from 2.0 to 1.3 eV as the bath temperature was increased from 40 to 80°C. The films deposited at 80°C showed good crystallinity and uniformly distributed over the surface of substrate with larger grain sizes. Therefore, the optimum bath temperature is 80°C