Correlation effects on the fine-structure splitting within the 3d9 ground configuration in highly-charged Co-like ions

A comprehensive theoretical study of correlation effects on the fine-structure splitting within the ground configuration 3d9 of the Co-like HI45＋, Ta46＋, W47＋, and Au52＋ ions is performed by employing the multi-configuration Dirac-Hartree- Fock method in the active space approximation. It shows that the core-valence correlation with the inner-core 2p electron is more significant than with the outer 3p and 3s electrons, and the correlation with the 2s electron is also noticeable. The core-core correlation seems to be small and can be ignored. The calculated 2D3/2,5/2 splitting energies agree with the recent electron-beam ion-trap measurements [Phys. Rev. A 83 032517 （2011）, Eur. Phys. J. D 66 286 （2012）] to within the experimental uncertainties.

Structure splitting framework for data-layout optimization

To improve data cache performance, optimizing program data layout by data reorganization has become an important method of decreasing the impact of increasing gap of speed between processor and memory. In this article, a structure splitting framework with an analysis model named structure field relation graph （SFRG） is presented to optimize program data layout. The SFRG can be used to quantify relationship between fields. It helps to find an optimal layout for structure as well as the optimal program data layout. And the data cache performance is improved through SFRG-based structure splitting. Experiments show that this framework is effective in optimizing program data layout and improving the performance of data cache and whole program.

Transition energy and dipole oscillator strength for 1s^22p-1s^2nd of Cr^(21+) ion

The transition energies, wavelengths and dipole oscillator strengths of 1s^22p-1s^2nd （3 ≤ n ≤ 9） for Cr^21＋ ion are calculated. The fine structure splittings of 1s^2nd （n ≤ 9） states for this ion are also calculated. In calculating energy, we have estimated the higher-order relativistic contribution under a hydrogenic approximation. The quantum defect of Rydberg series 1s^2nd is determined according to the quantum defect theory. The results obtained in this paper excellently agree with the experimental data available in the literature. Combining the quantum defect theory with the discrete oscillator strengths, the discrete oscillator strengths for the transitions from initial state 1s^22p to highly excited 1s^2nd states （n ≥ 10） and the oscillator strength density corresponding to the bound-free transitions are obtained.

Strain tunable quantum dot based non-classical photon sources

Semiconductor quantum dots are leading candidates for the on-demand generation of single photons and entangled photon pairs.High photon quality and indistinguishability of photons from different sources are critical for quantum information applications.The inability to grow perfectly identical quantum dots with ideal optical properties necessitates the application of post-growth tuning techniques via e.g.temperature,electric,magnetic or strain fields.In this review,we summarize the state-of-the-art and highlight the advantages of strain tunable non-classical photon sources based on epitaxial quantum dots.Using piezoelectric crystals like PMN-PT,the wavelength of single photons and entangled photon pairs emitted by InGaAs/GaAs quantum dots can be tuned reversibly.Combining with quantum light-emitting diodes simultaneously allows for electrical triggering and the tuning of wavelength or exciton fine structure.Emission from light hole exciton can be tuned,and quantum dot containing nanostructure such as nanowires have been piezo-integrated.To ensure the indistinguishability of photons from distant emitters,the wavelength drift caused by piezo creep can be compensated by frequency feedback,which is verified by two-photon interference with photons from two stabilized sources.Therefore,strain tuning proves to be a flexible and reliable tool for the development of scalable quantum dots-based non-classical photon sources.

Government Regulation,Enforcement,and Economic Consequences in a Transition Economy:Empirical Evidence from Chinese Listed Companies Implementing the Split Share Structure Reform

In a changing transition economy, Chinese government regulations that adopt the relatively simple bright line rule formula are enforceable in practice. Taking the early reform-oriented policies of the China Securities Regulatory Commission(CSRC) as an example, we find that the CSRC did not consider local enthusiasm for reform when allocating IPO resources because of the high enforcement costs involved. We also find that CSRC listed company regulations were enforced due to the lower costs involved in verifying regulatory violations, and that listed companies that completed the reform process were given priority in public refinancing. We present empirical evidence supporting the theoretical basis for the hypotheses outlined above. We also conclude that companies that completed the reform process in 2005 were of significantly higher quality and that the SEO regulation did not affect stock market efficiency. These findings enhance our understanding of the efficiency of government regulation in a transition economy.

Enhanced photochemical performance of hexagonal WO_3 by metal-assisted S–O coupling for solar-driven water splitting

Hybrid density functional calculations was used to comprehensively study the electronic structure of S-,Snand Pb-monodoped and（Sn,S）-and（Pb,S）-codoped hexagonal WO_3（h-WO_3）in order to improve their visible light photocatalytic activity.Results indicate that the（Sn,S）-and（Pb,S）-codoped h-WO_3 can realize a significant band gap reduction and prevent the formation of empty states in the valence band of h-WO_3,while Sn/Pb-monodoped h-WO_3 cannot,because in（Sn,S）-and（Pb,S）-codoping,the S-doping introduces the fully occupied S 3p states in the forbidden band gap of h-WO_3 and the acceptor metals（Sn and Pb）would assist the coupling of the introduced S with its nearest O.In particular,the（Sn,S）-codoped h-WO_3 has the narrowest band gap of 1.85 eV and highest reducing ability among the doped case.Moreover,the calculated optical absorption spectra show that（Sn,S）-codoping can improve the visible light absorption.In short,these results indicate that the（Sn,S）-codoped h-WO_3 is a promising material in solar-driven water splitting.

State ownership and firm performance: Empirical evidence from Chinese listed companies

While the relationship between state ownership and firm performance has been widely researched, the empirical evidence has provided mixed results. This study applies panel data regression techniques to 10,639 firm-year observations of nonfinancial Chinese listed firms during 2003–2010 to examine the relationship between state ownership and firm performance. The results show that state ownership has a U-shaped relationship with firm performance. The Split Share Structure Reform in2005–2006 played a positive role in enhancing the relationship between state ownership and firm profitability ratios. Although state ownership decreased significantly after 2006, it remains high in strategically important industry sectors such as the oil, natural gas and mining sector and the publishing, broadcasting and media sector. The findings reveal that a higher level of state ownership is superior to a dispersed ownership structure due to the benefits of government support and political connections. The Split Share Structure Reform made previously nontradable shares legally tradable, improving corporate governance and reducing the negative effect of non-tradable state shares.

New method for high performance multiply-accumulator design

This study presents a new method of 4-pipelined high-performance split multiply-accumulator (MAC) architecture, which is capable of supporting multiple precisions developed for media processors. To speed up the design further, a novel partial product compression circuit based on interleaved adders and a modified hybrid partial product reduction tree (PPRT) scheme are proposed. The MAC can perform 1-way 32-bit, 4-way 16-bit signed/unsigned multiply or multiply-accumulate operations and 2-way parallel multiply add (PMADD) operations at a high frequency of 1.25 GHz under worst-case conditions and 1.67 GHz under typical-case conditions, respectively. Compared with the MAC in 32-bit microprocessor without interlocked piped stages (MIPS), the proposed design shows a great advantage in speed. Moreover, an improvement of up to 32% in throughput is achieved. The MAC design has been fabricated with Taiwan Semiconductor Manufacturing Company (TSMC) 90-nm CMOS standard cell technology and has passed a functional test.

A 1-V 10-bit 80-MS/s 1.6-mW SAR ADC in 65-nm GP CMOS

This paper presents a 10-bit 80-MS/s successive approximation register（SAR） analog-to-digital converter （ADC） suitable for integration in a system on a chip（SoC）.By using the top-plate-sample switching scheme and a split capacitive array structure,the total capacitance is dramatically reduced which leads to low power and high speed.Since the split structure makes the capacitive array highly sensitive to parasitic capacitance,a three-row layout method is applied to the layout design.To overcome the charge leakage in the nanometer process,a special input stage is proposed in the comparator.As 80 MS/s sampling rate for a 10-bit SAR ADC results in around 1 GHz logic control clock,and a tunable clock generator is implemented.The prototype was fabricated in 65 nm 1P9M （one-poly-nine-metal） GP（general purpose） CMOS technology.Measurement results show a peak signal-to-noise and distortion ratio（SINAD） of 48.3 dB and 1.6 mW total power consumption with a figure of merit（FOM） of 94.8 fJ/conversion-step.