Optimal Layout of Displacement Measurements for Parameter Identification Process in Geomechanics

This paper focuses on designing the optimal layout of measurements for parameter identification problems in geomechanics, which are usually based on in situ displacements. The existence, uniqueness, and stability of the solution from the parameter identification process are thoroughly discussed. Based on these understandings of the problem, two algorithms are proposed as a means of automatically generating the optimal measurements. The validity of these algorithms is first proved by some academic examples, then these algorithms are applied to the Munich subway tunnel project. Good results are observed there.     

Using DAG Transformations to Verify Euler/Venn Homogeneous and Euler/Venn FOL Heterogeneous Rules of Inference

In this paper we will present a graph-transformation based method for the verification of heterogeneous first order logic (FOL) and Euler/Venn proofs. It has been shown that a special collection of directed acyclic graphs (DAGs) can be used interchangeably with Euler/Venn diagrams in reasoning processes [4]. Thus, proofs which include Euler/Venn diagrams can be thought of as proofs with DAGs where steps involving only Euler/Venn diagrams can be treated as particular DAG transformations. In the work reported here, we will show how the characterization of these manipulations can be used to verify Euler/Venn proofs. Also, a method for verifying the use of heterogeneous Euler/Venn and FOL reasoning rules will be presented that is also based upon DAG transformations.     

Assessing Concentration Dependence of FCC Metal Alloy Diffusion Coefficients Using Kinetic Monte Carlo

Intrinsic diffusion coefficients have been calculated for a solid solution binary fcc metal alloy with vacancies using grand canonical and kinetic Monte Carlo (MC) methods for a variety of model Hamiltonians. Model Hamiltonians include a kinetically and thermodynamically ideal case, solute-vacancy attraction and repulsion, and solute-solute attraction and repulsion. These model Hamiltonians are chosen to have constant average activation energies in order to focus on contributions from other thermodynamic and kinetic factors. The thermodynamic factor calculated using MC is compared to a mean-field regular solution model. It is shown that the mean-field model accurately predicts the thermodynamic factors for each model alloy Hamiltonian except for the alloys with a solute-solute interaction and concentration that are in the spinodal region (as predicted by the regular solution model). The MC determined concentration-dependent intrinsic diffusion coefficients are compared to values determined from the dilute five-frequency model and Darken and Manning analytical approximations. The results indicate that for a solid solution with known average barriers and vacancy concentration, Darken and Manning approximation-based analytic expressions and mean-field theory can be used to predict concentration-dependent diffusion coefficients within a factor of approximately three, provided the system is outside of the spinodal region. The good accuracy of this approximate approach follows from the fact that the thermodynamic factor is the main contribution to the concentration dependence of the diffusion constants, and that this thermodynamic factor is well described by mean-field theory.     

Removal of volatile flavour constituents from foods prior to analysis by gas-liquid chromatography

Volatile aroma constituents were removed from cooked chicken by vacuum distillation at 35°, followed by extraction of the aqueous distillate with ethyl chloride and concentration into a small volume of isooctane, to facilitate their analysis by gas-liquid chromatography. In an alternative procedure the meat, powdered in liquid nitrogen, was extracted with ethyl chloride, and the volatiles were separated from the lipid extract by vacuum distillation and similarly concentrated for application to the column. The second method gave the better extraction, particularly for components of higher boiling point. Optimum sensitivity and reproducibility were achieved by transfer of the whole of a concentrated extract of the volatiles from e.g. 100 g meat in 1–3 ml of solvent on to a column previously cooled to -60° to -70°, followed by rapid heating to 31° and subsequent temperature programming to 200° in the usual way. Compounds of chain length C₄ to C₁₅ (at least) could be quantitatively transferred to the column and determined by this procedure.     

The direct measurement of embryogenic volume and nucleo-cytoplasmic ratio during mouse pre-implantation development

Stringent selection mechanisms, in both internal and external fertilisation systems, reject all but a significant minority of the spermatozoa released at ejaculation. Sperm competition theory provides circumstantial evidence that the selection process involves mechanisms by which the quality of the fertilising spermatozoon is controlled, thereby ensuring that females and their offspring receive high quality genetic material. In this review we examine some of these selection processes to see whether they could be exploited for the improvement of laboratory tests of sperm quality. Such tests are not only required for clinical and agricultural purposes, but are increasingly needed in fields such as reproductive and environmental toxicology where the species requirement is much broader. Despite many years of research, sperm quality assessment methods continue to provide imprecise data about fertility; here we suggest that this may be a consequence of using tests that focus on the spermatozoa that would normally be unable to fertilise under natural conditions. To achieve fertilisation a spermatozoon must be capable of responding appropriately to external signalling stimuli; those involving protein kinase-regulated flagellar function seem especially influential in governing effects ranging from non-Mendelian inheritance in mammals to sperm chemotaxis in sea urchins. Examination of the elicited responses reveals considerable heterogeneity in all species. Here we propose that this level of heterogeneity is meaningful both in terms of understanding how spermatozoa from some individuals possess fertility advantages over spermatozoa from their rivals in sperm competition, and in that the heterogeneity should be exploitable in the development of more accurate laboratory tests.     

Reframing and restraining directives in the treatment of clinical depression.

We tested the effects of reframing and restraining directives on depression of high- and low-reactant clients. Reframing was more effective than restraining or control, and level of reactance had no effect. Restraining did not differ from control. Subjects were 74 moderately to severely depressed outpatients. Results are discussed in light of the compliance–defiance model of paradoxical interventions and psychological reactance theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A 5-Gb/s OEIC with voltage-up-converter

In this paper (based on our previous paper at ESSCIRC 2004, "A 2.4 GHz-Bandwidth OEIC with Voltage-Up-Converter," but new results for 4 Gb/s and 5 Gb/s have been added), an optoelectronic integrated circuit (OEIC) with an integrated voltage-up-converter (VUC) to enhance the frequency response of an integrated pin photodiode is presented. With the VUC a voltage of 11 V is generated on the chip without any additional external components. Thus, for a single-supply environment of 5 V the bandwidth of the OEIC is increased from 1.5 to 2.4 GHz. For data rates of 1, 3, 4, and 5 Gb/s at a bit error rate of 10/sup -9/, sensitivities of -29.3, -24.3, -22.9, and -20.5 dBm, respectively, were measured at a wavelength of 660 nm. For the implementation of the OEIC a modified 0.6-/spl mu/m silicon BiCMOS technology with f/sub T/=25 GHz is used.     

Single crystal flow reactor for studying reactivities on metal oxide model catalysts at atmospheric pressure to bridge the pressure gap to the adsorption properties determined under UHV conditions

A flow reactor for the investigation of heterogeneous catalytic reactions on single crystalline metal oxide model catalysts has been designed. It is located in a high pressure cell attached to an UHV analysis chamber where the model catalysts can be prepared and characterized by surface science techniques. It can also be run in a batch modus. After sample transfer the high pressure cell can be completely separated from the UHV chamber and it can be used for oxidation treatments and reaction studies at gas pressures up to 1 bar. A new heating system provides direct heating of the sample by laser light up to 1200 K. Product analysis is done by gas chromatography coupled with mass spectrometry, which allows detection in the ppb range. The single crystal flow reactor provides new insight into the atomic scale surface chemistry of metal oxides under real catalysis conditions and bridges the pressure gap for model systems prepared and characterized under UHV conditions. Results on the dehydrogenation of ethylbenzene to styrene over epitaxial potassium–iron oxide films are presented and correlated to thermal desorption measurements on the same films under UHV conditions.