Breakdown of self-similarity at the crests of large amplitude standing water waves

We study the limiting behavior of large-amplitude standing waves on deep water using high-resolution numerical simulations in double and quadruple precision. While periodic traveling waves approach Stokes's sharply crested extreme wave in an asymptotically self-similar manner, we find that standing waves behave differently. Instead of sharpening to a corner or cusp as previously conjectured, the crest tip develops a variety of oscillatory structures. This causes the bifurcation curve that parametrizes these waves to fragment into disjoint branches corresponding to the different oscillation patterns that occur. In many cases, a vertical jet of fluid pushes these structures upward, leading to wave profiles commonly seen in wave tank experiments. Thus, we observe a rich array of dynamic behavior at small length scales in a regime previously thought to be self-similar.Comment: 4 pages, 5 figures. Final version accepted for publicatio

Production of Propylene Oxide from Propylene Using Patented Silver Based Catalyst

Propylene oxide (PO) is an important intermediate in the manufacture of propylene glycol (PG), polyether polyols and many other products. Conventional production of propylene oxide has many drawbacks. The most common method, the chlorohydrin process produces chlorinated by products which must be disposed of. Other processes produce a co-product, like styrene, which adversely affects production economics. A team of scientists at the Council of Scientific and Industrial Research (CSIR) in New Delhi has recently applied for a patent for a catalyst that oxidizes propylene to PO in high yield. The primary motivation behind this project was the production of PO without the unwanted side products of traditional methods by using the direct oxidation in CSIR’s patent. Our proposed plant design produces 200 million lb/year of propylene oxide from propylene and will be located on the U.S. Gulf Coast. Our plant is divided into four sections, namely feed material pretreatment, direct oxidation reaction, initial separation, and final distillation. The byproducts include CO2, Acetal, Acrylic Acid, and Acrolein. CO2 is separated through adsorption-desorption cycle with monoethanolamine (MEA), other byproducts are separated by distillation, and PO product is 99.9822% pure by mass. The cost of purchase of propylene is $1,100/tonne and the selling cost of PO is$2500/tonne. The process has an estimated IRR of 81.91% and an NPV of $262,808,900.This report provides a detailed design and economic analysis for PO production in the Gulf Coast. Process flow sheets, energy and utility requirements and reactor design have been considered during our analysis below. The total cost of equipment is$35,715,726. Except for the most extreme variations of the price of PO, variable costs, fixed costs, and total permanent investment, the IRR remains strongly positive indicating the high chance of this project’s success even if factors outside of the group’s control negatively affect its economics. Due to its low risk and high reward, a license for the catalyst described in the patent should be acquired, and this process should be developed

Stepping Responses of Young and Old Adults to Postural Disturbances: Kinematics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111171/1/j.1532-5415.1994.tb04972.x.pd

Density matrix reconstruction from displaced photon number distributions

We consider state reconstruction from the measurement statistics of phase space observables generated by photon number states. The results are obtained by inverting certain infinite matrices. In particular, we obtain reconstruction formulas, each of which involves only a single phase space observable.Comment: 19 page

Orientation and Related Buoyancy Effects in Low-velocity Flow Boiling

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73459/1/j.1749-6632.2009.04081.x.pd

Space station impact experiments

Four processes serve to illustrate potential areas of study and their implications for general problems in planetary science. First, accretional processes reflect the success of collisional aggregation over collisional destruction during the early history of the solar system. Second, both catastrophic and less severe effects of impacts on planetary bodies survivng from the time of the early solar system may be expressed by asteroid/planetary spin rates, spin orientations, asteroid size distributions, and perhaps the origin of the Moon. Third, the surfaces of planetary bodies directly record the effects of impacts in the form of craters; these records have wide-ranging implications. Fourth, regoliths evolution of asteroidal surfaces is a consequence of cumulative impacts, but the absence of a significant gravity term may profoundly affect the retention of shocked fractions and agglutinate build-up, thereby biasing the correct interpretations of spectral reflectance data. An impact facility on the Space Station would provide the controlled conditions necessary to explore such processes either through direct simulation of conditions or indirect simulation of certain parameters

Candidate Pre-Mainsequence F Stars with Circumstellar Dust Identified Using Combined 2MASS and uvby Data

We propose a method that uses near-infrared plus uvby photometry to identify potentially extensive circumstellar dusty environment about F and A stars. The method has been applied to a sample of ~900 metal rich reddened F stars with 2MASS and uvby data, suggesting the presence of circumstellar dust emitting in the near infrared for ~70 stars. The log T_e - M_V diagram suggests that most, if not all, of them are likely pre-mainsequence (PMS). They seem to be consistent with being a continuation of the class of Herbig Ae/Be PMS stars into the spectral type F. Their number drops sharply downward of log T_e ~ 3.84 (spectral types later than ~F5), which may provide new clues to the PMS evolution of stars with 1 to 2 solar mass. We present a list of 21 most conspicuous candidate stars with circumstellar dust. About half of them are associated with the extended star-forming region around rho Oph. The brightest of these 21 stars, with V < 7.5, turn out to be IRAS sources, suggesting the presence of heated dust emitting in the far infrared. Also in this list, HD 81270 is reported as a very unusual star moving away from the Galactic plane at a projected speed of 70 km/sec.Comment: 8 pages, 4 figures, 1 table. To appear in ApJ, part 2, v. 570, 2002 May

The Burden and Management of Dyslipidemia: Practical Issues

Abstract The objective of this study is to describe briefly the burden of dyslipidemia, and to discuss and present strategies for health professionals to improve dyslipidemia management, based on a review of selected literature focusing on interventions for dyslipidemia treatment adherence. Despite the availability of effective lifestyle and pharmaceutical therapies for dyslipidemias, they continue to present a significant economic burden in the United States. Adherence to evidence-based guidelines for the treatment of dyslipidemias is unsatisfactory. The reasons for medication nonadherence are complex and specific to each patient. The lack of progress in achieving optimal lipid targets is caused by many factors: patient (medication adherence, cost of medication, literacy), medication (adverse effects, complexity of regimen), provider (lack of adherence to evidence-based practice guidelines, poor communication), and the US healthcare system (being focused on acute care rather than prevention, lack of continuity of care, general lack of use of an electronic health record). Combined interventions that target each part of the system have been effective in improving treatment adherence and achieving lipid goals. Patients, providers, pharmacists, and employers all play a role in management of dyslipidemia. No single approach will solve the complex issue of improving dyslipidemia management. The required lifestyle changes are known and effective medications are available. The challenge is for all interested parties?including nurses, nurse practitioners, doctors, pharmacists, other health care professionals, employers, and health plans?to help patients achieve behavioral changes. (Population Health Management 2012;15:302?308)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98471/1/pop%2E2011%2E0081.pd

Buildings behaving badly:A behavioral experiment on how different motivational frames influence residential energy label adoption in the Netherlands

Heating buildings contributes to approximately 36% of Europe’s energy demand and several EU member states have adopted mandatory energy labels to improve energy efficiency by promoting home weatherization investments. This paper focuses on the perception of the energy label for residential buildings in the Netherlands and the role of different frames (egoistic, biospheric and social norms and neutral frames) in motivating adoption of energy labels for housing. We used a behavioral email experiment and an online survey to investigate these motivational factors. We find that biospheric frames are weaker than the other three motivational frames in terms of engaging interest in the energy label, but that the biospheric frame results in higher willingness to pay (WTP) for the energy label. We also find that age (rather than income) correlates with higher willingness to pay for home energy labels