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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

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 electronic and boding structures of B-C-N thin films were investigated by using x-ray absorption near-edge structure (XANES) and valence-band photoelectron spectroscopy (PES). H-B-C-N ternary alloy films were formed when C atoms substituted B and N atoms and this resulted in C-N, C-B and N-B bonding structure.

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.