Role of optimization in interdisciplinary analyses of naval structures

The need for numerical design optimization of naval structures is discussed. The complexity of problems that arise due to the significant roles played by three major disciplines, i.e., structural mechanics, acoustics, and hydrodynamics are discussed. A major computer software effort that has recently begun at the David W. Taylor Naval Ship R&D Center to accommodate large multidisciplinary analyses is also described. In addition to primarily facilitating, via the use of data bases, interdisciplinary analyses for predicting the response of the Navy's ships and related structures, this software effort is expected to provide the analyst with a convenient numerical workbench for performing large numbers of analyses that may be necessary for optimizing the design performance. Finally, an example is included that investigates several aspects of optimizing a typical naval structure from the viewpoints of strength, hydrodynamic form, and acoustic characteristics

Extended hydrodynamic theory of the peak and minimum pool boiling heat fluxes

The hydrodynamic theory of the extreme pool boiling heat fluxes is expanded to embrace a variety of problems that have not previously been analyzed. These problems include the prediction of the peak heat flux on a variety of finite heaters, the influence of viscosity on the Taylor and Helmoltz instability mechanisms with application to film boiling and to the peak heat flux in viscous liquids, the formalization of the analogy between high-current-density electrolysis and boiling, and the description of boiling in the low-gravity limit. The predictions are verified with a large number of new data

PHASE CHANGE HEAT TRANSFER – A PERSPECTIVE FOR THE FUTURE

During the last half of the twentieth century, significant advances have been made in developing an understanding of phase change heat transfer (e.g., boiling and condensation). Further advances in phase change heat transfer will continue to take place motivated by new technologies such as microelectronics, thermal management in space, advanced terrestrial and space power systems and processing of designed materials. In the past, because of the complexity of the processes, very often we have “oversimplified”, maybe out of necessity, the modeling of the processes. The resulting weaknesses in our models and correlations have continued to haunt us whenever we have encountered new applications. In order to address the phenomena from basic principles, in my opinion, we need to pay attention to processes occurring at nano to micro to macro scales, capitalizing on recent advances that have been made in experimental and numerical techniques. These phenomena include nucleation, evolution, merger and breakup of vaporliquid interfaces, contact line behavior; coupling of the bulk and surface features of the solid; and the role of nano and micro inhomogeneties and intermolecular forces between solid and liquid. Prediction of nucleate boiling transfer is taken as an example to demonstrate the value of coupling different scales in meeting the overall objective

Investigation of Mechanisms Associated with Nucleate Boiling Under Microgravity Conditions

The focus of the present work is to experimentally study and to analytically/numerically model the mechanisms of growth of bubbles attached to, and sliding along, a heated surface. To control the location of the active cavities, the number, the spacing, and the nucleation superheat, artificial cavities will be formed on silicon wafers. In order to study the effect of magnitude of components of gravitational acceleration acting parallel to, and normal to the surface, experiments will be conducted on surfaces inclined at different angles including a downward facing surface. Information on the temperature field around bubbles, bubble shape and size, and bubble induced liquid velocities will be obtained through the use of holography, video/high speed photography and hydrogen bubble techniques, respectively. Analytical/numerical models will be developed to describe the heat transfer including that through the micro-macro layer underneath and around a bubble. In the micro layer model capillary and disjoining pressures will be included. Evolution of the interface along with induced liquid motion will be modelled. Subsequent to the world at normal gravity, experiments will be conducted in the KC-135 or the Lear jet especially to learn about bubble growth/detachment under low gravity conditions. Finally, an experiment will be defined to be conducted under long duration of microgravity conditions in the space shuttle. The experiment in the space shuttle will provide microgravity data on bubble growth and detachment and will lead to a validation of the nucleate boiling heat transfer model developed from the preceding studies performed at normal and low gravity (KC-135 or Lear jet) conditions

Optimization and transformation of Arundo donax L. using particle bombardment

An optimized particle bombardment protocol to introduce DNA into Arundo donax L. (giant reed) embryogenic callus cells was developed. The physical and biological parameters tested for optimal transient expression of ß-glucuronidase (GUS) and green fluorescent protein (GFP) genes were: helium pressure, distance from stopping screen to target tissue and vacuum pressure together with other factors such as gold microparticle size, DNA concentration and the number of bombardments. The highest transient GUS and GFP expression was obtained when cells were bombarded twice at 1100 psi, with 9 cm target distance, 24 mm Hg vacuum pressure, 1 mm gold particle size, 1.5 mg DNA per bombardment, three days pre-culture prior to bombardment and six days post bombardment culture. This is the first report of optimization of particle bombardment parameters for high-efficiency DNA delivery combined with minimum damage to target giant reed tissues.Key words: Arundo donax, particle bombardment, ß-glucuronidase (GUS), green fluorescent protein (GFP), transient gene expression, genetic transformation

Relationship between Sexual Fantasy, Sexual Communication, Personality Traits and Sexual Satisfaction in Married Individuals

The study aimed to understand the relationship between sexual fantasy, sexual communication, personality traits and sexual satisfaction in married individuals. Sexual fantasy as a variable has seldom been studied in the Indian context. The importance of sexual fantasies has been noted by therapists and researchers. Studying various aspects of sexual functioning in married life including, sexual communication and sexual satisfaction and personality traits would be beneficial. A cross sectional design with a total sample of 100 married individuals was considered. Tools were administered as online forms. Parametric and Non-parametric tests were used to find the correlation between Sexual fantasy and sexual satisfaction, sexual communication and sexual satisfaction and personality traits and sexual satisfaction. Results indicated that sexual fantasy and sexual satisfaction have a negative correlation, sexual communication and sexual satisfaction have a positive correlation and personality traits and sexual satisfaction also have a positive correlation. This study can be used to develop modules that might aid in marital and sex therapy. It may be useful in identifying any difficulties or issues which may help in providing appropriate timely interventio

Potential of Some Fungal and Bacterial Species in Bioremediation of Heavy Metals

Microorganisms including fungi and bacteria have been reported to extract heavy metals from wastewater through bioaccumulation and biosorption. An attempt was, therefore, made to isolate bacteria and fungi from sites contaminated with heavy metals for higher tolerance and removal from wastewater. Bacterial and fungal isolates were obtained from the samples collected from Karnal, Ambala and Yamunanagar districts of Haryana using enrichment culture technique. Bacterial and fungal isolates with tolerant up to 100 ppm concentration of heavy metals (Pb, Cd, Cr) were tested for their removal from liquid media containing 50 ppm concentration of Pb, Cd and Cr each. Five fungi (Penicillium chrysogenum, Aspegillus nidulans, Aspergillus flavus, Rhizopus arrhizus, Trichoderma viride) were also included in this study. Fungi Aspergillus nidulans, Rhizopus arrhizus and Trichoderma viride showed maximum uptake capacity of 25.67 mg/g for Pb, 13.15 mg/g for Cd and 2.55 mg/g of Cr, respectively. The maximum uptake capacity of tolerant bacterial isolates - BPb12 and BPb16, BCd5 and BCr14 were observed to be ~ 45 mg/g for Pb, 2.12 mg/g for Cd and 3.29 mg/g for Cr, respectively. This indicated the potential of these identified fungi and bacteria as biosorbent for removal of high concentration metals from wastewater and industrial effluents

Missed case of Axenfeld-Rieger syndrome: a case report

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