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In a recent paper published in this Journal, Lovell and Rouse (LR) proposed a modification of the standard data envelopment analysis (DEA) model that overcomes the infeasibility problem often encountered in computing super-efficiency. In the LR procedure one appropriately scales up the observed input vector (scale down the output vector) of the relevant super-efficient firm thereby usually creating its inefficient surrogate. By contrast, Chen suggested a different procedure that replaces input--output bundles that are found to be inefficient in standard DEA by their efficient projections. An alternative procedure proposed in this paper uses the directional distance function and the resulting Nerlove--Luenberger measure of super-efficiency. The fact that the directional distance function combines, by definition, features of both an input-oriented and an output-oriented model, generally leads to a complete ranking of the observations and is easily interpreted. A dataset on international airlines is utilized in an illustrative empirical application. Keywords: DEA; strong super-efficiency; efficiency ranking

As a consequence of the 1978 Chinese economic reforms, there have been a number of changes within China's industry. First, firms have been given limited autonomy in management. Second, firms now have control over the scale of production and production profitability after fulfilling the required plan. Third, some production factors have become firm controllable. Fourth, firms are now faced with a dual price system - a plan price and a market price. Thus, state-owned enterprises are now able to, at least, partially mimic the privately owned market-oriented firms. Given this situation, we examine the effect of economic reforms on the productivity of the Chinese state-owned enterprises within the Iron and Steel Industry using data envelopment analysis (DEA). In the context of a mixture of centrally planned and market economies with both controllable and uncontrollable production factors, we measure the technical efficiency and scale efficiency. The allocative efficiency measure for DEA employs an assurance region (AR) method, which illustrates the potential of AR in evaluating Chinese industrial performance within the reforms. In addition, the current study explores input congestion and scale economies. These two measures provide insight into and lessons for further economic reforms. This paper thus presents an extended use of DEA models in an attempt to improve and monitor firm-level productive efficiency of Chinese industry. Key words - data envelopment analysis (DEA), assurance region (AR), productive efficiency, economic reforms

X-ray absorption near-edge structure (XANES) and valence-band photoelectron spectroscopy (PES) were used to investigate the electronic and bonding structures of B-C-N thin films. The intensities of the sp2-bonded features in the C K-edge XANES spectra are found to generally decrease as the C concentration increases, whereas the intensities of the sp2-bonded features in the spectra of N K-edge XANES increase with the N concentration. The decrease of the intensities of the sp2-bonded features in the C and N K-edges XANES spectra correlates with the increase of the C/B and N/B concentration ratios and the increase of Young’s modulus. Valence-band PES spectra are found to be insensitive to the variations of the B and C concentrations in B-C-N compounds © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The electron field emission effects on chlorination (nitrogenated carbon nanotube (N-CNT):Cl) and oxidation (N-CNT:O) of N-CNT are studied. The results obtained are because of the formation of different bonds with carbon and nitrogen in the N-CNT during the process of chlorine-plasma treatment by the charge transfer, or else that changes the density of free charge carriers and enhances the field emission properties of N-CNTs:Cl (N-CNTs:O).

The dielectric properties associated with the electronic bonding structures of Si[O.sub.2] films are examined by using the Si [L.sub.3,2]- and O K-edge x-ray absorption near-edge structures (XANES) and valence-band photoemission spectroscopy (VB-PES) methods. The enhanced O 2p and Si 3p hybridization has shown the shortening of the average Si-O bond length, thus showing an increase of the density.

The electronic properties of amorphous carbon nitride were studied by x-ray-absorption near-edge structure (XANES) and valence-band photoelectron spectroscopy (PES). XANES spectroscopy is used to interpret the plausible electronic and bonding structures from the C and N K-edges of a-CN(sub x) thin films.

The effect of nitrogen partial pressure on amorphous carbon nitride (a-CNx) and laser fluence on amorphous carbon (a-C) films prepared by ultrafast high repetition rate pulsed laser deposition are studied. The chemical bonding structure of the films is investigated by X-ray photoelectron spectroscopy, Raman spectroscopy, and Fourier transform infrared analysis.

The properties of the a-C: H:OH films deposited by the 'dip' technique are studied by several nondestructive characterization techniques (optical and photothermal deflection spectroscopy in the visible photon energy range, Raman spectroscopy, profilometry, photoluminescence, electron-spin-resonance characterization of the paramagnetic centers). The as-prepared material exhibits several characteristics comparable to those floppy, polymer-like amorphous carbons.

Abstract: Deposition by RF magnetron sputtering of PbZr0.52Ti0.48O3 (PZT) ferroelectric thin films on two types of colossal magneto-resistive (CMR) oxide electrodes, La0.67Sr0.33MnO3 (LSMO) and La0.67Ca0.33MnO3 (LCMO), is demonstrated in this work. The multiferroic heterostructure is grown on a STO substrate, which causes a 〈001〉 preferred orientation to develop. Ferroelectric, retention of polarisation and local piezoelectric properties were measured for assessing the success of the integration from the ferroelectric point of view. Remnant polarisation P r and coercive field E c were found to be ∼40 μC/cm2 and ∼100 kV/cm, respectively. Films presented good retention of polarisation and piezoresponse loops. These results show that ferroelectric layers with good functionality can be grown on CMR oxide films, and open the possibility of designing a piezoelectrically driven spin valve memory cell device based on this heterostructure. [Copyright &y& Elsevier]

X-Ray diffraction (XRD) and B, N and C K-edges X-ray absorption near-edge structure (XANES) measurements have been performed to study the BxCyNz ternary compounds. XRD reveals that the films contain carbon nitride, boron carbide, and boron nitride compounds. The combination of B, N and C K-edges XANES results reveal the presence of B&z.sbnd;N, B&z.sbnd;C, N&z.sbnd;C, and C&z.dbnd6;N local bonding structures in BxCyNz, indicating that boron–carbon–nitride thin films have a ternary phase, rather than a mixture of segregated binary phases. [Copyright &y& Elsevier]

We have investigated the infrared transparency and electron spin resonance (ESR) signal of natural and 13C tetrahedral amorphous carbon (ta-C) films deposited by mass selected ion beam. In order to assess the significance of the results, which are averaged over the film, we have monitored the film through micro-Raman, showing that lateral fluctuation in the sp3 content are limited. We show that ta-C films are transparent to IR radiation and that no hyperfine splitting can be observed in ESR spectra of 13C samples. The room-temperature line-width is the same (ΔHpp=5.5±0.1 G) in all samples. This is attributed to the strong signal narrowing caused by spin delocalization and short-range interaction at room temperature. [Copyright &y& Elsevier]

This work investigates the C K-edge x-ray absorption near-edge structure (XANES), valence-band photoelectron spectroscopy (PES), and Fourier transform infrared (FTIR) spectra of Si-doped hydrogenated amorphous carbon films. The C K-edge XANES and valence-band PES spectra indicate that the sp2/sp3 population ratio decreases as the amount of tetramethylsilane vapor precursor increases during deposition, which suggest that Si doping% enhances sp3 and reduces sp2-bonding configurations. FTIR spectra show the formation of a polymeric sp3 C–Hn structure and Si–Hn bonds, which causes the Young’s modulus and hardness of the films to decrease with the increase of the Si content. [ABSTRACT FROM AUTHOR]