Integration of Kano’s Model into quality function deployment (QFD)

Viability of a product or service in the market depends upon the satisfaction that it can extend to its customers through quality. Quality function deployment (QFD) is a tool that gathers voice of customer (VoC) and inducting the expected features in the final product. It is also desirable that the practitioners of QFD must extend due importance to latent expectations of the customers, which in turn may fulfill overall customer satisfaction for a product or service. Kano et al. (J Jpn Soc Qual Control, 14:39–48, 1984; 1996) and Kano (2001) have suggested a method to identify the different categories of requirements through customer responses. Based on the QFD and Kano model analysis, a function has been proposed to adjust the traditional improvement ratio (Tan and Shen, Total Qual Manag 11:1141–1151, 2000) for each product or service attribute to recognize the importance of a attribute, which can be helpful in developing a product or service in such a manner that maximum customer satisfaction can be achieved. The proposed methodology has been illustrated using customer survey data.     

Magnetic and dielectric studies of barium hexaferrite (BaFe 12 O 19 ) ceramic synthesized by chemical route

Barium hexaferrite BaFe12O19 (BHF) ceramic was synthesized by chemical route on sintering at 1050 °C for 12 h. The synthesized material was characterized by XRD, SEM, AFM and TEM analysis. Metal oxide stretching frequencies corresponding to Fe-O, Ba-O, and Fe-O-Fe bands are confirmed by FTIR studies. The hexagonal nature of the BHF ceramic was confirmed by TEM analysis and Rietveld refinement with space group P63/mmc. The particle size observed by TEM is 175 nm. The root means square and average roughness were found to be 61.048 nm and 44.025 nm respectively. The M-T and M-H hysteresis loop indicates temperature dependent ferromagnetic behavior of BHF ceramic. The temperature and frequency dependent dielectric properties were explained by Maxwell-Wagner theory. The value of dielectric constant (ε′) for BHF ceramic was found to be 22× 103 at 100 Hz and 483 K.     

Defect studies of ZnSe nanowires

During the synthesis of ZnSe nanowires various point and extended defects can form, leading to observed stacking faults and twinning defects, and strong defect related emission in photoluminescence spectra. In this paper, we report on the development of a simple thermodynamic model for estimating the defect concentration in ZnSe nanowires grown under varying Se vapour pressure and for explaining the results of our experimental findings. Positron annihilation spectroscopy was used successfully for the first time for nanowires and the results support predictions from the defect model as well as agreeing well with our structural and optical characterization results. Under very high Se vapour pressure, Se nodules were observed to form on the sidewalls of the nanowire, indicating that beyond a limit, excess Se will begin to precipitate out of the liquid alloy droplet in the vapour-liquid-solid growth of nanowires.     

Photoelectrochemical analysis of band gap modulated TiO2 for photocatalytic water splitting

In this study the photocatalysis efficiency of titania (TiO₂) is increased by conjugating it with folic acid (FA) molecules through a silane linker (APTMS) layer. Electrochemical testing demonstrated higher negative open circuit potential (OCP) in surface engineered TiO₂ as compared to TiO₂ indicating higher Schottky barrier leading to suppressed electron–hole pair recombination. The photocurrent density under no bias conditions demonstrated 55% increase in modified titania due to lower band gap and suppressed electron hole pair recombination. The mechanism behind higher photocatalytic properties of surface engineered TiO₂ was derived using density functional theory (DFT).     

Study on the thermal decomposition of NaBH4 catalyzed by ZrCl4

The catalytic effect of zirconium tetrachloride (ZrCl₄) on the thermal dehydrogenation of NaBH₄ has been studied. The ZrCl₄ reduced to ZrCl₂ and metallic zirconium which exhibit the high catalytic activity during thermal dehydrogenation. The activation energy corresponding to dehydrogenation of NaBH₄ is remarkably reduced to 180 kJ/mol in the presence of a catalyst as compared to pure-NaBH₄ which was found to be 275 kJ/mol under the similar experimental conditions. The reduced activation energy leads to decreased onset dehydrogenation temperature (<300 °C). A substantial amount of sodium remained at the end of the dehydrogenation of catalyzed sample. The low-temperature dehydrogenation of catalyzed NaBH₄ could be useful to manage the evaporation of sodium metal.     

Wigner–Ville distribution based diffraction phase microscopy for non-destructive testing

ABSTRACT

The paper proposes an approach for non-invasive measurement of displacement derivatives and defect identification using an optical interferometric technique based on diffraction phase microscopy. Our approach relies on the application of Wigner–Ville distribution method in diffraction phase microscopy for directly extracting the phase derivative information, which is subsequently utilized for non-destructive deformation metrology. In addition, the proposed method offers good computational efficiency and robustness against noise for fast defect inspection. The performance of the proposed method is validated by experimental results.     

Interference based marking method for toric contact eye lens inserts

Toric contact eye lenses are designed to address general blurring that occurs due to uneven cornea which is known as astigmatism. For proper functioning of toric lenses their orientation with respect to the eye is critical. So toric lenses are manufactured with some form of marking which helps in deciding the orientation with respect to the eye. In this research paper a novel marking method based on the interference principle is proposed for toric lenses. Mathematical modeling followed by experiments was done to prove the concept of interference based marking. The proposed marking method is a mask-less, single step clean process.     

Phase and morphology evolution study of ball milled Mg–Co hydrogen storage alloys

Ball milled Mg–Co alloys with body-centered cubic structure (BCC) may absorb hydrogen at 258 K with a hydrogen capacity around 3 mass%. The phase and morphology evolution process of Mg₅₀Co₅₀ alloys ball milled for 0.5 h–400 h was studied by X-ray diffraction and scanning electron microscope. The formation mechanism of the Mg₅₀Co₅₀ alloys was clarified. Mg₅₀Co₅₀ alloys ball milled for various durations were found to present different hydrogen storage properties which could result from the phase and morphology difference in these samples.     

A Comparative Study of Submicron Phonon Transport Using the Boltzmann Transport Equation and the Lattice Boltzmann Method

The subcontinuum energy transport mechanism in solids can be explained by the Lattice Boltzmann Method (LBM), a discrete representation of the Boltzmann Transport Equation (BTE). The present study focuses on a detailed comparison of the LBM and BTE. Results reveal that at continuum scale, the LBM follows the BTE almost precisely. However, as the device dimensions are reduced, approaching the ballistic limit, the LBM deviates from the BTE results in terms of thermal property estimation. The inherent nonisotropic lattice configuration has a dominant contribution to the performance of the LBM. A threshold length scale is also proposed for successful implementation of the LBM solver.     

Site-wide low-grade heat recovery with a new cogeneration targeting method

One of the key performance indicators for designing site utility systems is cogeneration potential for the site. A new method has been developed to estimate cogeneration potential of site utility systems by a combination of bottom-up and top-down procedures, which allows systematic optimization of steam levels in the design of site utility configurations. A case study is used to illustrate the usefulness of the new cogeneration targeting method and benefits of optimizing steam levels for reducing the overall energy consumptions for the site. Techno-economic analysis has been carried out to improve heat recovery of low-grade waste heat in process industries, by addressing a wide range of low-grade heat recovery technologies, including heat pumping, organic Rankine cycles, energy recovery from exhaust gases, absorption refrigeration and boiler feed water heating. Simulation models have been built for the evaluation of site-wide impact associated with the introduction of each design option in industrial energy systems in the context of process integration. Integration of heat upgrading technologies within the total site has been demonstrated with a case study for the retrofit scenario.