Applied Mechanics and Materials Vols. 284-287

Abstract: A major problem for the implementation of microelectroremoval is the cost and the design of the tool electrode. An effective nanoscale processing for yield improvement was developed using microelectroremoval and a designed twin-cylinder tool as a precision reclamation retrieval system to remove the defective indium tin oxide (ITO) thin-film nanostructures from the optical PET surfaces of digital paper. By establishing a recycling process using the ultra-precise removal of nanostructures, the optoelectronic semiconductor industry can effectively recycle defective products, minimizing both production costs and pollution. In the current experiment, small thickness of the anode, combined with enough electric power and provided a larger discharge space, and better removal effect. A large diameter of the cylinder acthode accompanied by a small gap-width between the cathode and the workpiece, takes less time to do the same amount of ITO removal. A higher rate of removal of the defective ITO nanostructures corresponds to high temperature, a large electrolyte flow rate with a high rotational speed of the electrodes. A faster feed rate of color filters combined with a higher electric current produces a fast removal rate. A small edge angle of the anode also provides higher current density, which is advantageous for ITO removal.

Abstract: Cationic carriers including polyethylenimine, liposomes, and chitosan have been used to transfer plasmid DNA in vitro by condensing anionic DNA. Here, oligochitosan (OC) was found to have capacity for in-vitro gene delivery in four cell lines. Plasmid containing green fluorescent protein (GFP) gene was used as a reporter gene. The transfection efficacy and cell viability of the transfection vehicles were analyzed by using a high-throughput image analyzer. We found that DNA polyplexes formed by high dosage of OC could be efficiently delivered into the cells. The combination of OC and polyethylenimine (PEI) were found to significantly enhance the fluorescence protein expression. The introduction of oligochitosan in PEI-mediated transfection could increase the transfection efficacy and could reduce the toxicity of PEI. Additionally, the synergistic effects of PEI and OC were confirmed in CHO, Caco2, Hep-SK, and 3T3 cell lines. The detailed mechanism of PEI and oligochitosan on transfection was investigated by using gel retardation and DNase degradation experiments. A facile and inexpensive construction of gene delivering vehicles was developed herein by using oligochitosan and PEI.

Abstract: A kinetic model with effect of water content for enzyme-catalyzed citronellyl laurate was developed. These models incorporate the combined influences of established kinetics model with the function model on the effect of initial water content with kinetic parameters. The model development was carried out by performing a linear and nonlinear regression based on the behavior of the kinetic parameter profiles and validated with experimental data. Using the developed models, the influence of water content towards the enzyme-catalyzed initial rate of reaction was theoretically explained. It has been shown that the proposed model have good agreement between experimental data and intends to capture the effect of water content towards the conversion of ester. With this model, the optimal value of initial water content for this process could be estimated.

Abstract: The light reflectivity of multiwall carbon nanotubes (MWCNTs) in the 1150nm - 1755 nm wavelength range with pattern-less and pattern-grown nanotubes are studied. From test measurements it concludes that when the multiwall carbon nanotubes are pattern-grown fabricated its return loss is linearly proportional to the nanotubes grown height and consequently the pattern-grown CNTs can be implemented as a good optical attenuator. However for high density nanotubes fabricated with pattern-less process it has greater than 45 dB return loss, this is equivalent to have less than 0.56% reflectivity; with this high absorption effect it can be utilized as a black body absorber.

Abstract: The long slender cylinder often suffers the high Reynolds number in ocean environment, and its dynamic characters and vortex shedding modes vary with a number of mechanical, physical and fluid–solid parameters.Considering the vertical vibration, caused by floating platform, of top tensioned riser (TTR), an analysis method for the coupled vibration of parameter excited vibration and vortex-induced vibration is presented in this paper. With the section rotation and shear deformation due to the bending large displacement of TTR, a coupled vibration model of parameter excited vibration and vortex-induced vibration is put forward. And the vortex-induced vibration (VIV) of a TTR for 1500m water depth is analyzed based on the model. The results show that the vertical vibration caused by floating platform increases transverse vibration displacement of TTR,especially in in-line direction.

Abstract: A morphing of a system is capable of changing the shape from the cruise to dash configurations. During the motion, the aerodynamic and structural characteristics can be varied tremendously, and the new shape will induce the different aeroelastic stability behavior. Thus, the purpose of this study is to investigate the flutter analysis of the folding wing structure including the effect of various parameters such as fold angles et al. of the composite laminates structures. For doing this these works, the aero-elastic analysis of folding wing is performed with respect to the parameters using PK method. Also, Finite Element Method is used in structural analysis, and Doublet Lattice Method is applied in aerodynamic analysis. Generally, the dynamic pressure and frequency during the flutter are sensitive to the structural characteristic, thus the flutter mode alteration is occurred by changed natural frequencies. Also, the alteration causes the flutter dynamic pressure variation. Therefore, results represent the aeroelastic stability variation due to the folding wing system including the effects of ply angles of composite laminates.

Abstract: The short-circuit phenomenon is one common error in the operation of electronic circuit. Short-circuit will cause the electrical components damage and the incorrect function in PCB. In general, the detection of short-circuit is performed by using the electrode probe to contact each pad in single PCB or the probe card in mass production of PCD. Due to the fast development of circuit layout, the size of IC with pads is getting smaller; therefore, it is much difficult to detect short-circuit in PCB by the pads-contact inspection. This paper presents a method to detect short-circuit area in PCB without the use of electrode probe, which employs the electromagnetic signals to sense and identify the change of electromagnetic induced by short-circuit. We design an electromagnetic sensing probe which comprises of an equivalent circuit to detect the change of electromagnetism in PCB, and employ an X-Y table for automatic positioning. Instead of tiny electrode probe manufacturing, the electromagnetic sensing method (ESM) is able to detect the short-circuit area inside the multi-layer PCB. In addition, the inspective module with ESM can be designed to be a portable instrument without the space limitation. The article shows the verification of proposed system with the scanning pitch is from 5 to 20 mil line width, the working distance of sensing probe is from 1 to 20 mm, and 4 layers PCB measurement. We also experiment the real case detection by using the ESM in PCB and display ESM can successful indicate the probable area of short-circuit.

Abstract: Contour Positioning System (CPS) is a new system invented for electric vehicles to calculate the remaining battery capacity for reaching a desired destination. Instead of using conventional electric car estimation in terms of distance, a CPS system can figure out extra energy needed when an electric car is traveling on different contour lines. Extra current will be drawn for generating torque required by the electric car on an inclined plane, for instance traveling uphill. By using coordinate conversion, sets of longitude and latitude readings can be converted into distance difference along the pathway and the elevation levels difference are calculated; the extra force and torque needed along an inclined plane can be further counted which will then lead to the extra current drawn from the electric car's battery pack. Data collections and real-time validations have been done to clarify the calculation results. By performing a series of battery capacity calculation, CPS can give a higher precision and accuracy of remaining battery life to reach the desired location

Abstract: A novel design of butterfly-type laser module packaging using transistor outline (TO) structures is proposed. The cost down and fabrication time savings for fabrication of the module packagings are obtained, and the yield rate and the coupling efficiency of butterfly-type laser module are enhanced. The post-weld-shift (PWS) correction uses laser hammer technique in coaxial-type laser modules is studied experimentally and numerically. Experimental results show that the PWS of a coaxial laser module welded by a three-beam laser system can be corrected by applying laser hammer on the opposed tilt direction of welded components to realign the fiber back closer to its optimum position. In addition, the coupling efficiency increased up to 20 % was obtained by laser hammer.Further, the numerical calculations of the finite-element method analysis was in good agreement with the experimental results of the tilt angles of PWS ranged from 0.4 x 10-2 to 3.4 x 10-2 degree. The results of this study showed that the PWS state of being properly adjusted in coaxial laser module packages and led to fabricating reliable optoelectronic packaging with high yield.

Abstract: The dynamic analysis of a geared rotor-bearing system with time-varying gear mesh stiffness and pressure angle is presented in this paper. Although there are analyses for both of the gear and rotor-bearing system dynamics, the coupling effect of the time-varying mesh and geared rotor-bearing system is deficient. Therefore, the pressure angle and contact ratio of the geared rotor-bearing system are treated as time-varying variables in the proposed model while they were considered as constant in previous models. The gear mesh stiffness is varied with different contact ratios of the gear pair in the meshing process. The nonlinear equations of motion for the geared rotor-bearing system are obtained by applying Lagrange’s equation and the dynamic responses are computed by using the Runge-Kutta numerical method. Numerical results of this study indicated that the proposed model provides realistic dynamic response of a geared rotor-bearing system.