市场化与腐败类型的地区差异——基于职务犯罪起诉书数据的多层分析

市场化与腐败之间的关系是腐败研究领域中一个争论不休的话题。通过对中国职务犯罪起诉书的数据分析,研究发现:市场化程度会显著影响地区之间在腐败类型上的差异,处于市场化程度比较高的环境下,官员卷入交易型腐败的概率高于自体型腐败。因此,市场化不是简单地增加或者减少了腐败的总量,而是通过改变腐败类型的结构化特征来影响腐败的。此外,研究还暗示,中国由于地区间经济形态的差异,导致腐败的结构性差异,不同地区要针对不同的腐败形态制定个性化和差异化的反腐败策略,有的放矢,以便更有效地打击腐败。

Silicon photonic transceivers for application in data centers

Global data traffic is growing rapidly,and the demand for optoelectronic transceivers applied in data centers(DCs)is also increasing correspondingly.In this review,we first briefly introduce the development of optoelectronics transceivers in DCs,as well as the advantages of silicon photonic chips fabricated by complementary metal oxide semiconductor process.We also summarize the research on the main components in silicon photonic transceivers.In particular,quantum dot lasers have shown great potential as light sources for silicon photonic integration—whether to adopt bonding method or monolithic integration—thanks to their unique advantages over the conventional quantum-well counterparts.Some of the solutions for highspeed optical interconnection in DCs are then discussed.Among them,wavelength division multiplexing and four-level pulseamplitude modulation have been widely studied and applied.At present,the application of coherent optical communication technology has moved from the backbone network,to the metro network,and then to DCs.

Interdependence between the stock market and the bond market in one country:evidence from the subprime crisis and the European debt crisis

Background:Once a global financial crisis breaks out,the interdependence between different financial markets suddenly increases and leads to a significant contagion.Methods:With 39 countries used as samples,this paper analyzes the interdependence between the stock market and the government bond market during the crisis periods.Results:It proves that the investor focuses more on the safety of their portfolio so there is neither a flight from quality nor a positive spillover during a crisis period.When one market is safer than the other market in the same country,a flight to quality occurs between the two markets;however,when the two markets in one country are both risky,negative spillover appears between these two markets.Conclusions:This means a flight to quality from the stock market to the short-term government bond will occur more frequently than will occur from the stock market to the long-term government bond markets.In addition,a flight to quality always emerges in developed markets,while negative spillovers take place in emerging markets and in the PIIGS countries(Portugal,Italy,Ireland,Greece,and Spain,referred to hereon as“PIIGS”)in the European Debt Crisis.

Preparation of natural brucite nanofibers by the dispersion method

The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate （OT） as the dispersant at a dispersant/fiber mass ratio of 0.15：1, dispersing for 30 min at a water/solid mass ratio of 20：1. The prepared nanofibers were characterized with X-ray diffraction （XRD）, scanning electron microscope （SEM）, and transmission electron microscope （TEM）. It is shown that the prepared single brucite nanofiber is around 30 nm in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost.

Effect of alkali-activation on aluminosilicate-based cementitious materials

High-performance aluminosilicate-based cementitious materials were produced with fly ash from a coal power plant as one of the major raw materials. The structures of fly ash containing aluminosilicate-based cementitious materials were compared before and after treatment by the methods of nuclear magnetic resonance （NMR） and scanning electron microscopy （SEM）. During the 28 d curing time, the compressive strength of water glass and fly ash samples increased from 9.08 MPa to 26.75 MPa. The results show that most of the stiff shells are destroyed after mechanical grinding and chemical activation. Magic angle spinning （MAS） NMR of 27Al shows that the wide peak becomes narrow and the main peak shifts to the direction of low field, indicating the decrease of polymerization degree, the enhancing of activity, the decrease of six-coordination structure, and the increase of small and symmet- rical four-coordination polyhedron structure within the aluminum-oxygen polyhedron network. Comparisons between MAS NMR of 29Si with different treatments suggest that QO disappears, the quantity of Q2 increases, and the quantity of Q4 decreases. The polymerization degree of silicon-oxygen is reduced, and the potential activity of fly ash is increased.

Effect of Sb composition on the band alignment of InAs/GaAsSb quantum dots

Aiming to achieve InAs quantum dots(QDs) with a long carrier lifetime,the effects of Sb component in cap layers on the band alignment of the InAs/GaAsSb QDs have been studied.InAs QDs with high density and uniformity have been grown by molecular beam epitaxy.With increasing Sb composition,the InAs/GaAsSb QDs exhibit a significant redshift and broadening photoluminescence(PL).With a high Sb component of 22%,the longest wavelength emission of the InAs/GaAs_(0.78)Sb_(0.22) QDs occurs at 1.5 μm at room temperature.The power-dependence PL measurements indicate that with a low Sb component of 14%,the InAs/GaAs_(0.86)Sb_(0.14) QDs have a type-Ⅰ and a type-Ⅱ carrier recombination processes,respectively.With a high Sb component of 22%,the InAs/GaAs_(0.78)Sb_(0.22) QDs have a pure type-Ⅱ band alignment,with three type-Ⅱ carrier recombination processes.Extracted from time-resolved PL decay traces,the carrier lifetime of the InAs/GaAs_(0.78)Sb_(0.22) QDs reaches 16.86 ns,which is much longer than that of the InAs/GaAs_(0.86)Sb_(0.14) QDs(2.07 ns).These results obtained here are meaningful to realize high conversion efficiency intermediate-band QD solar cells and other opto-electronic device.

Bank loan information and information asymmetry in the stock market:evidence from China

In this study,we use bank loan information to construct proxies for corporate transparency and examine whether these measures reflect information asymmetry in the stock market.Our analysis is based on a novel dataset of stock transactions and bank loans of all publicly listed firms on the Shenzhen Stock Exchange,covering January 2008 to June 2013.We find that firms with outstanding loans have a lower level of information asymmetry in the stock market,whereas firms with defaulted loans have a higher level of asymmetry.Further evidence demonstrates that the effect of loan default on information asymmetry in the stock market is more pronounced when these loans are borrowed from joint-equity commercial banks or multiple banks and when the default occurs under inactive market conditions.Our results remain robust to a series of endogeneity and sensitivity tests and provide suggestive evidence of a close connection between the credit loan and stock markets.

Broadband chirped InAs quantum-dot superluminescent diodes with a small spectral dip of 0.2 dB

We report on the fabrication and characterization of InAs/GaAs chirped multilayer quantum-dot superluminescent diodes(CMQD-SLDs)with and without direct Si doping in QDs.It was found that both the output power and the spectral width of the CMQD-SLDs were significantly enhanced by direct Si doping in the QDs.The output power and spectral width have been increased by approximately 18.3%and 40%,respectively.Moreover,we shortened the cavity length of the doped CMQD-SLD and obtained a spectral width of 106 nm.In addition,the maximum output power and spectral width of the CMQD-SLD doped directly with Si can be further increased to 16.6 mW and 114 nm,respectively,through anti-reflection coating and device packaging.The device exhibited the smallest spectral dip of 0.2 dB when the spectrum was widest.The improved performances of the doped CMQD-SLD can be attributed to the direct doping of Si in the QDs,optimization of device structure and device packaging.

Why pregnant women delay to initiate and utilize free antenatal care r service:a qualitative study in the Southern District of Mzimba,Malawi

Aim:The study aimed to explore factors related to the initiation and utilization of focused antenatal care(FANC)in the Southern District of Mzimba,Malawi.Methods:This study used an exploratory qualitative design.Total of 22 in-depth interviews with pregnant women and community midwife assistants were conducted from December 2015 to January 2016 in Mzimba.Thematic analysis approach was adopted to identify the facilitator and harriers of the FANC initiation and utilization.Results:Facilitator of FANC initiation and utilization included seeking pregnancy confirmation,medical treatment for an existing health problem and the support by community health extension workers.Barriers included the additional cost to free FANC service,lack of essential equipment,unfriendly adolescent reproductive health service,and HIV stigma.Conclusion:Early initiation of FANC relies on both woman’s awareness and community support.Promoting the use of FANC should focus on creating an enabling environment,e.g.,increasing investment of essential medical equipment,reducing additional costs of FANC services,eliminating the discrimination against adolescent pregnancy and people living with HIV,and strengthening health personnel’s training.

神经网络法预测汽车轮胎的微观与宏观性能

有限元(FE)分析已成为轮胎行业虚拟研究轮胎备受青睐的工具,因为它能模拟轮胎胎体的接合部细节。然而,在轮胎设计开发中应用有限元分析依然非常耗时,且花费不菲。在此,对应用各种人工神经网络(ANN)结构来预测轮胎性能进行了评估,以便选择最有效和最高效的结构。这样我们可在用花费高得多的全过程有限元分析进行证实预测的性能之前,以花费不多的费用进行广泛的参数研究,以便优化轮胎设计。

Iodine Content of Processed Foods and Condiments Sampled in China, 2017-2019

Introduction: Facing the challenge of increasing consumption of processed foods in China, along with the demand for salt reduction, and dynamic adjustment of universal salt iodization (USI) policy, it is necessary to timely evaluate the distribution of iodine content in processed foods and condiments, so as to provide more accurate data for population dietary iodine intake assessment. Methods: From markets in 6 cities and e-commerce platforms, cereal, tuber, legume, meat, fish, egg, and dairy products, and condiments, consumed by volunteers who attended in iodine intake investigation, and top selling products in particular with well-noted brands were preferentially sampled during 2017 to 2019. After being mixed and homogenized, each sample was detected by ICP-MS method. The range and medium of iodine content in each type of product were given. Results: After merging samples with close value in the same style of the same brand, and screening out samples with no added salt or low sodium content (≤120 mg/100g), total 725 data were sub-grouped and analyzed. In comparison with the 95th percentile of the iodine distribution in relative nature source, assessed by our previous study, nearly 77% of products made from grains, potatoes, beans, nuts, livestock and poultry meat were presumed to be processed with iodized salt. In somewhat, related with sodium value marked on food labeling, the median iodine ranged from 1.1 mg/100g to 149 mg/100g. The variation of iodine in egg, milk and fish made products, and seaweed or with seaweed products was greatly affected by the background of ingredients, the median content most floated between 12.8 mg/100g and 86.8 mg/100g, even up to 1800 mg/100g in seasoned seaweed. Based on the frequency of iodine digital and the ratio of iodine to sodium, it was speculated that nearly 90% of soy sauce and 73.5% of other seasonings like vinegar, sauce, paste, etc., were not added iodized salt, with overall median iodine 4.0 mg/100g and 12 mg/100g respectively. Conclusion: Using iodized salt in processed foods is an approach of USI police. Affected by the nature backgrounds of ingredients composed, the amount of salt used, and the regulated fortification level, iodine content in each kind of product varied largely. It’s important to establish a monitoring system in processed foods, as well as fortification salt, to control the benefit and risk of iodine health.

A Neural Network Approach to Predicting Car Tyre Micro-Scale and Macro-Scale Behaviour

Finite Element (FE) analysis has become the favoured tool in the tyre industry for virtual development of tyres because of the ability to represent the detailed lay-up of the tyre carcass. However, application of FE analysis in tyre design and development is still very time-consuming and expensive. Here, the application of various Artificial Neural Network (ANN) architectures to predicting tyre performance is assessed to select the most effective and efficient architecture, to allow extensive parametric studies to be carried out inexpensively and to optimise tyre design before a much more expensive full FE analysis is used to confirm the predicted performance.

A multi-scale framework for life reduction assessment of turbine blade caused by microstructural degradation

The prolonged thermal exposure with centrifugal load results in microstructural degradation,which ultimately leads to a reduction in the fatigue and creep resistance of the turbine blades.The present work proposes a multi-scale framework to estimate the life reduction of turbine blades,which combines a microstructural degradation model,a two-phase constitutive model,and a microstructure-dependent fatigue and creep life reduction model.The framework with multi-scale models is validated by a Single Crystal(SC)Ni-based superalloy at the microstructural length-scale and is then applied to calculate the microstructural degradation and the fatigue and creep life reduction of turbine blades under two specific service conditions.The simulation results and quantitative analysis show that the microstructural degradation and fatigue and creep life reduction of the turbine blade are heavily influenced by the variations in the proportion of the intermediate state,namely,the maximum rotor speed status,in the two specific service conditions.The intermediate state accelerates the microstructural degradation and leads to a reduction of the life,especially the effective fatigue life reserve due to the higher temperature and rotational speed than that of the 93%maximum rotor speed status marked as the reference state.The proposed multi-scale framework provides a capable approach to analyze the reduction of the fatigue and creep life for turbine blade induced by microstructural degradation,which can assist to determine a reasonable Time Between Overhaul(TBO)of the engine.

How mutual funds respond to asymmetric feedback tradingin China’s stock market

Previous studies show that individual investors play a dominant role in China's stock market.Their behavior of chasing-rise being stronger than killing-fall leads to asymmetry of feedback trading.Our article investigates how mutual funds react to this market force.Using China's stock and fund data from 2003 to 2019,we find that mutual funds tend to hold fewer shares when asymmetric feedback trading of the relevant stock gets more intense.This negative relationship is robust after controlling past returns,turnover rates,and firm risk factors,moreover,it attenuates when the market sentiment is bullish or when stocks are allowed short-selling.Further results show that mutual funds'selling towards asymmetric feedback trading does not make excess return but leads to significant risk reduction.Our findings may be related to uncertainty associated with asymmetric feedback trading,and thus support the limit market participation theory from the second largest stock market.

On group structures of strategic-form games

There are two recognized classes of strategic-form symmetric games,both of which can be conveniently defined through the corresponding player symmetry groups.We investigate the basic properties of these groups and several related concepts.We generalize the notion of coveringness and adapt their results to characterize these player symmetry groups.We study the relationships between the coveringnesses of various symmetry groups.Our results demonstrate that these symmetry groups have rich mathematical structures that are of game theoretical and economic interests.

Corrosion Behavior of High-Chromium Alloys in Molten LiCl-KCl Eutectic

Pyrochemical reprocessing utilizing a molten LiCl-KCl eutectic medium is regarded as the most promising approach for recovering uranium and transuranic elements from spent metallic nuclear fuels.However,the harsh corrosiveness of molten chloride poses a significant challenge to the durability of structural materials.Herein,we report the corrosion behavior of 304 SS,316H SS and Inconel 800H in LiCl-KCl eutectic salt at 550°C for 100 h under an argon atmosphere.Experimental results indicate that all three materials can form a rather continuous Cr_(2)O_(3)-based scale through oxidation reaction at the beginning,but only the scale developed on 800H maintains excellent protection against corrosion throughout the entire exposure period.In contrast,both 304 SS and 316H SS experience considerable active dissolution on the bare substrate under a detached scale.We suggest that the primary reasons for the outstanding resistance of 800H to molten salt corrosion are the high concentration of noble Ni in the system,which lowers the inclination for active dissolution,and the beneficial addition of Al,which accelerates the formation of a less defective Cr_(2)O_(3)-based scale.Our work offers an in-depth understanding on the corrosion performance of high-Cr alloys in molten chloride,insights critical for the selection and subsequent development of structural materials for pyrochemical reprocessing applications.

A physically-based representative stress methodology for predicting stress rupture life of Ni-based DS superalloy

Smooth and three types of U-shape single-edge notched plate specimens adopted to experimentally investigate stress rupture behavior of Ni-based Directionally Solidified(DS)superalloy at 850℃ exhibit notch weakening effect and multi-source cracking initiation near the notch root.However,stress rupture behavior of smooth and V-shape notched round bars at 1040℃ revealed by Li et al indicates notch strengthening effect and creep micro-holes originating mostly from the central portion.A combined creep-viscoplastic constitutive model is employed to analyze the distribution of stress,strain and stress Triaxial Factor(TF)near the notch root.The different stress distribution and creep restraint between asymmetric notched plate specimens and symmetric notched round bars are the main reasons for the corresponding failure mechanism.Meanwhile,a good qualitative relationship exists between TF value and stress rupture life of notched specimen.Especially,the area with maximum TF value(TF_(max))is highly consistent with creep damage initiation region.Hence,based on the distribution characteristics of the initial tensile loading,a representative stress method independent of time-changing creep load at the location of TF_(max) is conducted for life prediction.The predicted results of both smooth and notched plate specimens and round bars agrees well with the experimental results.

Bicriteria Algorithms for Approximately Submodular Cover Under Streaming Model

In this paper,we mainly investigate the optimization model that minimizes the cost function such that the cover function exceeds a required threshold in the set cover problem,where the cost function is additive linear,and the cover function is non-monotone approximately submodular.We study the problem under streaming model and propose three bicriteria approximation algorithms.Firstly,we provide an intuitive streaming algorithm under the assumption of known optimal objective value.The intuitive streaming algorithm returns a solution such that its cover function value is no less thanα(1−ϵ)times threshold,and the cost function is no more than(2+ϵ)^(2)/(ϵ^(2)ω^(2))⋅κ,whereκis a value that we suppose for the optimal solution andαis the approximation ratio of an algorithm for unconstrained maximization problem that we can call directly.Next we present a bicriteria streaming algorithm scanning the ground set multi-pass to weak the assumption that we guess the optimal objective value in advance,and maintain the same bicriteria approximation ratio.Finally we modify the multi-pass streaming algorithm to a single-pass one without compromising the performance ratio.Additionally,we also propose some numerical experiments to test our algorithm’s performance comparing with some existing methods.

Average Amount and Stability of Available Agro-Climate Resources in the Main Maize Cropping Regions in China during 1981–2010

The available agro-climate resources that can be absorbed and converted into dry matter could directly affect crop growth and yield under climate change. Knowledge of the average amount and stability of available agro-climate resources for maize in the main cropping regions of China under climate change is essential for farmers and advisors to optimize cropping choices and develop adaptation strategies under limited resources. In this study, the three main maize cropping regions in China—the North China spring maize region（NCS）, the Huanghuaihai summer maize region（HS）, and the Southwest China mountain maize region（SCM）—were selected as study regions. Based on observed solar radiation, temperature, and precipitation data, we analyzed the spatial distributions and temporal trends in the available agro-climate resources for maize during 1981-2010. During this period, significantly prolonged climatological growing seasons for maize [3.3, 2.0, and 4.7 day（10 yr）^-1 in NCS, HS, and SCM] were found in all three regions. However, the spatiotemporal patterns of the available agro-climate resources differed among the three regions. The available heating resources for maize increased significantly in the three regions, and the rates of increase were higher in NCS [95.5℃ day（10 yr）^-1] and SCM [93.5℃ day（10 yr）^-1] than that in HS [57.7℃ day（10 yr）^-1].Meanwhile, decreasing trends in the available water resources were found in NCS [–5.3 mm（10 yr）^-1] and SCM[–5.8 mm（10 yr）^-1], whereas an increasing trend was observed in HS [3.0 mm（10 yr）^-1]. Increasing trends in the available radiation resources were found in NCS [20.9 MJ m^-2（10 yr）^-1] and SCM [25.2 MJ m^-2（10 yr）^-1], whereas a decreasing trend was found in HS [11.6 MJ m^-2（10 yr）^-1]. Compared with 1981–90, the stability of all three resource types decreased during 1991–2000 and 2001–10 in the three regions. More consideration should be placed on the extreme events caused by more intense climate fluctuations. The results can provide guidance in the development of suitable adaptations to climate change in the main maize cropping regions in China.

SKEWNESS OF RETURN DISTRIBUTION AND COEFFICIENT OF RISK PREMIUM

The skewness of the return distribution is one of the important features of the security price.In this paper,the authors try to explore the relationship between the skewness and the coefficient ofrisk premium.The coefficient of the risk premium is estimated by a GARCH-M model,and the robustmeasurement of skewness is calculated by Groeneveld-Meeden method.The empirical evidences forthe composite indexes from 33 securities markets in the world indicate that the risk compensationrequirement in the market where the return distribution is positively skewed is virtually zero,andthe risk compensation requirement is positive in a significant level in the market where the returndistribution is negative skewed.Moreover,the skewness is negatively correlated with the coefficient ofthe risk premium.