Modeling and analysis of boring bar vibration response in internal turning due to variation of the amount of DVA rubber in finish boring cut

Journal of Mechanical Science and Technology - In boring processes, excessive vibration often occur due to low tool stiffness. To solve this problem, a mechanical vibration suppression called...     

Veterinary drug residues in seafood inspected by the European Union, United States, Canada, and Japan from 2000 to 2009

Veterinary drugs are used to treat or prevent a wide array of production-related diseases in aquaculture. Residues of these drugs in seafood products may pose risks to consumers, prompting governments to set drug residue tolerance levels and inspect seafood for violations of these standards. This study characterizes veterinary drug inspection policies and violations among four inspecting bodies (European Union (E.U.), United States (U.S.), Canada, and Japan), using government-collected veterinary drug violation data from 2000 to 2009. Most veterinary drug violations were detected in species that are commonly farm-raised. Asian seafood products, including shrimp and prawns, catfish (or fish sold as catfish), crab, tilapia, eel, and Chilean salmon were most frequently in violation of veterinary drug residue standards. Vietnam had the greatest number of violations among exporting countries. Concentrations of most veterinary drugs in seafood found in violation did not differ between inspecting bodies that reported drug concentrations. Transparency in seafood inspection reporting varied widely among inspecting bodies. Estimation of violations in the untested fraction of seafood was precluded by a lack of information from inspecting bodies regarding the distinction between targeted and random sampling. Increased transparency could facilitate a more rigorous characterization of public health risks from consuming imported seafood.     

Application of CALPHAD to high pressures

The current methods of performing CALPHAD (CALculation of PHAse Diagrams) calculations of high-pressure phase equilibria often lead to spurious predictions of negative thermal expansion or negative heat capacity at high pressures. It is shown that the origin of the problem lies in an incompatibility between the temperature dependence of the widely used SGTE (Scientific Group Thermodata Europe) database and that of typical equations of state of the Mie–Grüneisen type. This inconsistency is also linked to the general problem of describing mechanical instability in CALPHAD. In the present work, a new free energy formulation is developed specifically for inclusion of pressure effects in CALPHAD methodology. It is based on an interpolation between SGTE data at low pressures and the quasiharmonic lattice model at high pressures. The new formulation is constrained to physically credible predictions of the thermophysical properties, while preserving the simplicity of the CALPHAD method. Examples are given of calculations of thermophysical properties and high-pressure phase equilibria in Al, Si, MgO, Fe and the Al–Si binary alloy system.     

Cultural perspective on work and family: Dual-earner Israeli Jewish and Arab families at the transition to parenthood.

Parents' functioning in the work and family roles was examined in traditional and modern societies at the transition to parenthood. Participants were 162 dual-earner Israeli Jewish and Arab families, who were interviewed and observed in dyadic and triadic interactions. Arab parents reported better adaptation to work following the first childbirth, and the triadic family process in Jewish families was more cohesive. Child care arrangements, part-time employment, easier infant temperament, and lower separation anxiety predicted maternal readaptation to work. Traditional sex-role attitudes, career centrality, full-time employment, and marital satisfaction predicted fathers' work adaptation. Parents' family focus, marital satisfaction, and responsive parenting correlated with a cohesive triadic process. Discussion considered the impact of nuclear- and extended-family living arrangements on the emerging work and family roles in young couples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Te vapor pressure dependence of the pn junction properties of PbTe liquid phase epitaxial layers

The pn junction characteristics of the PbTe epitaxial layers grown on PbTe substrates are investigated. Both the substrate crystals and the epitaxial layers are grown under controll Te vapor pressures. The ideality factors n of pn junctions decrease close to 1 in the temperature region from 40K to about 120K, but then increase with increasing temperature. The increase of n is more pronounced for higher Te vapor pressure. As a possible origin of the recombination current, deep levels with E_d=0.09 eV are found from Hall measurements for pn junctions grown under higher Te vapor pressure.     

The combined effect of additives and processing on the thermal stability and controlled release of essential oils in antimicrobial films

Essential oils (EOs) have a long history as food preservatives and many advantages compared to synthetic preservatives. The major limitation of EOs as antimicrobial agents incorporated into a polymeric matrix is their low thermal stability and their high volatility from polymers. This study suggests a new methodology approach to bypass the key limitations of adding EOs into active packaging, as food preservatives. Antimicrobial active films based on linear low density polyethylene (LLDPE) and Montmorillonite (MMT) were produced by incorporating the EO thymol in a stepwise procedure. The production of the film composites, containing thymol, has been conducted, under a protocol of three stages: (1) production of a highly porous nano composite master batch; (2) impregnation of thymol into the master batch; and (3) cast film extrusion. Adding MMT incorporated together with a foaming agent at stage‐(1) increased significantly the heat stability of the EO during melt processing at stage‐(3). Finally, the film obtained showed a high antimicrobial activity. The results obtained have proven the synergistic interaction between MMT, foaming agent and thymol. As the MMT content in the film increased, the loss of EO in the processing decreased, leading to a natural antimicrobial film with improved antibacterial properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40564.     

Learning to Take Actions

We formalize a model for supervised learning of action strategies in dynamic stochastic domains and show that PAC-learning results on Occam algorithms hold in this model as well. We then identify a class of rule-based action strategies for which polynomial time learning is possible. The representation of strategies is a generalization of decision lists; strategies include rules with existentially quantified conditions, simple recursive predicates, and small internal state, but are syntactically restricted. We also study the learnability of hierarchically composed strategies where a subroutine already acquired can be used as a basic action in a higher level strategy. We prove some positive results in this setting, but also show that in some cases the hierarchical learning problem is computationally hard.     

Depressive symptoms across older spouses: Longitudinal influences.

Cross-sectional findings that depressive symptoms in one older spouse influence those of the other and that marital closeness increases the influences (R.B. Tower & S.V. Kasl, 1995) were tested longitudinally. Independent interviews in 1982, 1985, and 1988 with spouse-pairs who participated in the Established Populations for the Epidemiologic Study of the Elderly showed that changes in depressive symptoms in one older spouse contributed to changes in depressive symptoms in the other. For wives in 1985 and for husbands in 1988, a spouse's baseline depressive symptoms also contributed independent variance to an increase in respondent's score on the Center for Epidemiologic Studies Depression Scale. These findings were stronger when a couple was close. These results held when known intrapersonal risk factors and the health status of the spouse were controlled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Complexity parameters for first order classes

We study several complexity parameters for first order formulas and their suitability for first order learning models. We show that the standard notion of size is not captured by sets of parameters that are used in the literature and thus they cannot give a complete characterization in terms of learnability with polynomial resources. We then identify an alternative notion of size and a simple set of parameters that are useful for first order Horn Expressions. These parameters are the number of clauses in the expression, the maximum number of distinct terms in a clause, and the maximum number of literals in a clause. Matching lower bounds derived using the Vapnik Chervonenkis dimension complete the picture showing that these parameters are indeed crucial. This work has been partly supported by NSF Grant IIS-0099446. A preliminary version of this paper appeared in the proceeding of the conference on Inductive Logic Programming 2003. Most of this work was done while M.A. was at Tufts University. Editors: Tamás Horváth and Akihiro Yamamoto