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This paper examines the degree of similarity in assortative pairing for life history strategy, mate value, delinquency, and sensational interests for same-sex friends compared to opposite-sex romantic partners in persons across a variety of nations that are culturally quite different, in spite of some sharing the same language. Specifically, we sampled participants from: (1) Tucson, Arizona, United States of America; (2) Hermosillo, Sonora, Mexico; (3) San Jose, Costa Rica; and (4) Leicester, England. Due to the structure of the data and the nature of our research questions, we used a relatively new statistical tool called the Continuous Parameter Estimation Model (CPEM; Gorsuch, 2005), in order to estimate and compare assortative pairing coefficients between the four cultures. In all four cross-cultural western cultures replications, the inter-rater reliabilities, perceived assortative pairing coefficients, and actual assortative pairing coefficients of all four traits were generally substantial in magnitude, positive, and statistically significant among pairs of social partners as well as pairs of romantic partners.

The front transparent conductive oxide layer is a source of significant optical and electrical losses in silicon heterojunction solar cells because of the trade-off between free-carrier absorption and sheet resistance. We demonstrate that hydrogen-doped indium oxide (IO:H), which has an electron mobility of over 100 cm(2)/V s, reduces these losses compared to traditional, low-mobility transparent conductive oxides, but suffers from high contact resistance at the interface of the IO:H layer and the silver front electrode grid. This problem is avoided by inserting a thin indium tin oxide (ITO) layer at the IO:H/silver interface. Such IO:H/ITO bilayers have low contact resistance, sheet resistance, and free-carrier absorption, and outperform IO:H-only or ITO-only layers in solar cells. We report a certified efficiency of 22.1% for a 4-cm(2) screen-printed silicon heterojunction solar cell employing an 10:H/ITO bilayer as the front transparent conductive oxide. (C) 2013 Elsevier B.V. All rights reserved.

Rear side floating junction solar cells with localised contacts often show parasitic shunting losses. For p-type material, this is due to tunnelling that takes places between the passivating n + -type rear junction and the p + -type back surface field region underneath localised rear contacts. To avoid this, the rear metallisation and the passivation layer should electronically be separated. Alternatively, the (induced) doping concentration of these layers could be optimised. This paper discusses the constraints met upon incorporation of such lowly recombinative structures into a low-cost solar cell process on multi-crystalline Si (mc-Si) material.

Surface recombination velocities as low as 10 cm/s have been obtained by treated atomic layer deposition (ALD) of Al 2 O 3 layers on p-type CZ silicon wafers. Low surface recombination is achieved by means of field induced surface passivation due to a high density of negative charges stored at the interface. In comparison to a diffused back surface field, an external field source allows for higher band bending, that is, a better performance. While this process yields state of the art results, it is not suited for large-scale production. Preliminary results on an industrially viable, alternative process based on a pseudo-binary system containing Al 2 O 3 are presented, too. With this process, surface recombination velocities of 500–1000 cm/s have been attained on mc-Si wafers.

Optimization of plasma enhanced chemical vapor deposited hydrogenated silicon nitride (SiN x :H) towards bulk passivation of multi-crystalline silicon cells has been carried out for both low and high frequency (HF) plasma deposition. Experimental results showed that bulk passivation is not caused by hydrogen incorporation in the top silicon layer during deposition and subsequent diffusion towards the bulk during firing, but that it is released from the SiN x :H film. We demonstrate that the amount of passivation depends on the SiN x :H density and its resistance against etching in HF. Optimization of the density, varying deposition temperature and using hydrogen dilution resulted in an optimized passivation.

High impurity concentrations do not allow the direct use of upgraded metallurgical grade (UMG) Si for PV production. A newly developed prototype inductive plasma-purification system andprocess allowedthe significant reduction of the elements B, C, O, P, Al, Ca, Fe and Ti, depending on the duration of the treatment. Based on this type of purification, it is shown that subsequent appropriate low-cost cell-processing yields homogeneously distributed energyconversion efficiencies throughout the cast ingots. Stabilisedcell efficiencies of up to 14.7% were already experimentally shown to be attainable on highly B-doped (ro0:1O cm) 102 cm 2 multi-crystalline Si substrates of high purity. On plasma-purifiedUMG p-type 0.1–0.2 O cm ingots, efficiencies of up to 12.38% are reached, to be compared with about 10.12% on the same material without prior plasma treatment. Some light-induced degradation is present on processedsamples, which is most likely linkedto the presence of metastable boron–oxygen complexes in the material, andresults in stabilisedefficiencies of, respectively, 12.19% and 10.00%. r 2002 Elsevier Science B.V. All rights reserved.

This paper describes how an interface between the dynamic simulator SpeedUp and the Shell Multivariable Optimising Controller has been developed and applied to the design of a new PP-splitter. This interface is used for the integration of the process design with the design of the process control system. It allows for a direct evaluation of disturbance behaviour of the controlled process with respect to possible design alternatives. Issues addressed are the choice of the control method, the location of quality measurement instruments and equipment sizing.

This paper addresses the problem of melt index (MI) control in the polymerisation of propylene in slurry reactors. Good MI control performance is usually hampered by measurement delays and a low sampling frequency. The traditional solution to the control problem is to control the hydrogen concentration in the reactor (H 2 serves as the chain transfer agent in the reaction and therefore has a good correlation with the MI). The H 2 concentration in the gas cap of the reactor is relatively easy to measure and therefore chosen to close a SISO control loop. However, this concentration is not always a good measure for the H 2 concentration in the slurry phase where the reactions occur. Consequently, MI variations can still be large at good control of H 2 in the gas cap. In the present paper, the use of a soft sensor for the H 2 concentration in the slurry phase is investigated by means of simulation. When used in combination with a model predictive control method, it is shown that plant performance significantly improves both at disturbances and at grade changes.

This paper describes how an interface between the dynamic simulator Speed Up and the Shell Multivariable Optimising Controller has been developed and applied to the design of a new PP-splitter. This interface is used for the integration of the process design with the design of the process control system. It allows for a direct evaluation of disturbance behaviour of the controlled process with respect to possible design alternatives. Issues addressed are the choice of the control method, the location of quality measurement instruments and equipment sizing.

Results shown of the identification of a three input two output pilot plant evaporative crystallizer (970 litre), in which the Crystal Size Distribution (CSD) is the main characteric of the process to be modelled, and subsequently to be controlled. The experimental situation is characterized by short observaron times and a bad signal to noise ratio of the CSD measurement device. A three step identification procedure is applied, consisting of high order ARX modelling reduction though approximate realization based on step response matrices, and finally output error optimization in a pseudo-canonical (overlaping) state space parametrization.

An automatic dilution unit which enables fast and representative dilution of a process stream, down to the solids concentration required for Fraunhofer diffraction size measurements, has been developed. This unit has been built and tested on a 1-m3 continuous crystallizer producing ammonium sulphate. A Malvern 2600c particle size analyser is used as the actual measuring device. The combined system of dilution unit and sizer is integrated into a supervisory control system. From experimental data, the reproducibility of the average size (m4/m3), the second, third and fourth moments of the Particle Size Distribution (PSD) is estimated to be 2.2%, 2.7%, 2.3%, 3.3%, respectively. The observed trends of the PSD are in accordance with results obtained by sieve analysis. The measurement frequency attained is 30 times per hour.

The UA2 experiment has collected large samples of W and Z events during recent runs at the CERN p p Collider at s = 630 GeV . These samples have been used to perform precise measurements of the masses of the W and Z bosons. After a careful analysis of systematic errors, an improved result is obtained for the mass ratio mwmz. This provides a new value for the weak mixing parameter sin2θw. Furthermore, it can be combined with recent measurements of the Z mass from e+e− colliders to give an absolute measurement of the W mass, leading to the result mw=80.49±0.43 (stat) ± 0.24 (syst) GeV.

For effective control of crystallizers, multivariable controllers are required. To design such controllers, a model in state-space representation is required. In deriving such a model, the population balance has to be transformed into a set of ordinary differential equations. Three transformation methods were reported earlier in the literature. Two of these methods are limited to MSMPR crystallizers. The third method has no restrictions in its applicability, however it results in very high model orders. Therefore another technique is proposed which can also be applied directly on experimental data without the intermediate step of calculating the kinetic parameters.

Poly(A)-rich RNA has been isolated from calf thymus and translated in vitro in a rabbit reticulocyte translation system. Three peptides with Mr = 58,000, 33,000, and 13,000 were specifically immunoprecipitated from the translation products with calf terminal deoxynucleotidyltransferase antiserum. An oligo(dT)-purified preparation of calf terminal transferase competed with only the Mr = 58,000 peptide in the immunoprecipitation reaction. The anti-terminal transferase serum did not precipitate a Mr = 58,000 peptide from translation products of spleen or liver mRNA, but it did precipitate the Mr = 33,000 and 13,000 peptides from products of spleen mRNA and a Mr = 13,000 peptide from products of liver mRNA. In addition, when an affinity-purified antibody to calf terminal transferase was used, only a Mr = 58,000 peptide was immunoprecipitated from the translation products of calf thymus mRNA, and none was immunoprecipitated from spleen or liver mRNA products. This antibody also precipitated a Mr = 58,000 peptide from the cell lysates of calf thymocytes labeled in vitro with [35S]methionine. These results demonstrate that calf terminal transferase is biosynthesized as a Mr = 58,000 peptide.