基于信差的我国绿色债券定价影响因素分析

根据国家印发文件《绿色债券支持项目目录(2021年版)》中的定义,绿色债券是满足发行透明、环保承诺等条件,将募集资金专门用于支持符合规定条件的绿色产业、绿色项目或绿色经济活动,依照法定程序发行并按约定还本付息的有价证券。中国于2015年首次引进绿色金融理念。2015年7月16日,新疆金凤科技股份有限公司在香港联交所发行了首单永续绿色债券,同时在海外完成3亿美元债券的发行,票面利率2.5%,期限3年,并由国际专业第三方风险管理服务机构DNV认证,成为中资企业发行的首个绿色债券。同年国家发改委印发的一系列规范文件提出了我国现阶段发行绿色债券的要求,标志着绿色债券在中国的正式开端,从此我国绿色债券市场蓬勃发展。根据《中国绿色债券市场报告2021》,截止至2021年底中国在境内外市场累计发行贴标绿色债券3,270亿美元(约2.1万亿元人民币),按符合CBI定义的绿色债券累计发行量,中国是仅次于美国(3055亿美元)的全球第二大绿色债券市场。

基于多尺度低秩模型的心脏磁共振成像方法研究

本文提出一种基于多尺度低秩模型(MSL,Multi-Scale Low rank)的磁共振成像方法,该方法将矩阵分解成多尺度的块低秩矩阵之和,并将多尺度块低秩矩阵之和的最小化作为约束条件用于磁共振成像.两种不同的心脏磁共振数据用于验证本文所提出算法重构磁共振成像的精度.实验结果表明,相比于k-t SLR(k-t Sparsity Low Rank)和L+S(Low Rank plus Sparse)方法,所提出的MSL方法具有更好的重建效果,获得更高的重构信差比(signal to error ratio),并具有更好地结构相似性,但需要更长的重构时间.

Lower bound on BER performance for maximal ratio combining with weighting errors

The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower bounds for different channel Doppler spectra are derived. Based on the obtained lower bounds on mean squared channel estimation errors, the limits on bit error rate （BER） for maximal ratio combining （MRC） with Gaussian distributed weighting errors on independent and identically distributed （i. i. d） fading channels are presented. Numerical results show that the BER performances of ideal MRC are the lower bounds on the BER performances of non-ideal MRC and deteriorate as the maximum Doppler frequency increases or the SNR of channel estimate decreases.

SUBSPACE-BASED NOISE VARIANCE AND SNR ESTIMATION FOR MIMO OFDM SYSTEMS

This paper proposes a subspace-based noise variance and Signal-to-Noise Ratio (SNR) estimation algorithm for Multi-Input Multi-Output (MIMO) wireless Orthogonal Frequency Division Multiplexing (OFDM) systems. The special training sequences with the property of orthogonality and phase shift orthogonality are used in pilot tones to obtain the estimated channel correlation matrix. Partitioning the observation space into a delay subspace and a noise subspace, we achieve the measurement of noise variance and SNR. Simulation results show that the proposed estimator can obtain accurate and real-time measurements of the noise variance and SNR for various multipath fading channels, demonstrating its strong robustness against different channels.

The design of adaptive sigma-delta A/D converter

The signal to noise ratio （SNR） of conventional sigma delta analog to digital converter （∑△ADC） reduces with input signal strength. The existing concept of adaptive quantization is applied to the design of ∑△ADC to improve SNR with high dynamic range. An adaptive algorithm and its circuit implementation is proposed. Because of the error due to the circuit implementation, an error self-calibration circuit is also designed. Simulation results indicate that SNR can he nearly independent of the signal strength.

Anisotropic nonlinear diffusion approach to single image resolution enhancement

In many image resolution enhancement applications,the blurring process of the imaging system is unknown.This paper discusses the problem of single image blind resolution enhancement without estimating the point spread function(PSF).A regularization model is constructed for image enhancement based on the prior informaton of image error and image gray value,which does not need any prior information of PSF.Moreover,through the solution of Euler equations,an anisotropic nonlinear diffusion equation are obtained,which can avoid the high computational cost of regularization model.Furthermore,in order to get sub-pixel superresolved image,the regularization model for image enhancement is extended to the enlargement of image,which can enlarge and enhance image at the same time.Last,to get clearer edges,a high frequency enhancement filter is used on the superresolved image.Numerical results show that the new model can get much clearer super-resolution images than traditional methods,and the peak signal to noise ratios (PSNRs) are also higher than traditional methods.

Network-aware perceptual error concealment method for H.264 video with side information

In order to improve the video quality of transmission with data loss,a spatial and temporal error concealment method was proposed,which considered both the state information of the network and the perceptual weight of the video content.The proposed method dynamically changed the reliability weight of the neighboring macroblock,which was used to conceal the lost macroblocks according to the packet loss rate of the current channel state.The perceptual weight map was utilized as side information to do weighted pixel interpolation and side-match based motion compensation for spatial and temporal error concealment,respectively.And the perceptual weight of the neighboring macroblocks was adaptively modified according to the perceptual weight of the lost macroblocks.Compared with the method used in H.264 joint model,experiment results show that the proposed method performs well both in subjective video quality and objective video quality,and increases the average peak signal-to-noise ratio(PSNR) of the whole frame by about 0.4 dB when the video bitstreams are transmitted with packets loss.

IMPROVED MLV FILTER TO REMOVE MULTIPLICATIVE NOISE

More methods can be used to remove the additive noise, such as the Mean of Least Variance (MLV) filter. When the signal is noised by the multiplicative noise, it is difficult to remove. The paper presents an improved filter to remove multiplicative noise by changing the multiplicative noise to the additive noise, and then using the MLV-like to remove the additive noise. The simulation results show that the performance is better than Minimum Coefficient of Variation (MCV) filter and MLV filter. Both one-dimension and image experiments demonstrate its theoretical performance.

谈谈我厂规避坏账风险的做法

销售是企业生产经营成果的实现过程,从资金运动过程看,是从成品资金转化为货币资金的过程。这一过程有时候是从成品资金直接转化为货币资金,即销售时钱货两清;有时候则分为两个阶段,先从成品资金转化为结算资金,形成应收账款,然后再从结算资金转化为货币资金,收回应收账款。目前。

HIGH SNR SUM CAPACITY ANALYSIS OF BD MIMO BC SYSTEMS WITH IMPERFECT CSI

We investigate the sum capacity of Block Diagonalization precoding Multiple Input Mul-tiple Output Broadcast Channels(BD MIMO BC) with imperfect Channel State Information(CSI) at the base station.Since it is difficult to obtain the exact expression,a lower and an upper bounds of the sum capacity under Gaussian channel estimation errors are drived instead.Analyses show that the gap between two bounds is considerably tight at all Signal to Noise Ratio(SNR) region.From the lower bound of the sum capacity,we can see that the multiplexing gain tends to be zero at high SNR region,which indicates that the BD MIMO BC system with channel estimation errors is interference-limited at high SNR.

A continuous differentiable wavelet threshold function for speech enhancement

Enhanced speech based on the traditional wavelet threshold function had auditory oscillation distortion and the low signal-to-noise ratio (SNR). In order to solve these problems, a new continuous differentiable threshold function for speech enhancement was presented. Firstly, the function adopted narrow threshold areas, preserved the smaller signal speech, and improved the speech quality; secondly, based on the properties of the continuous differentiable and non-fixed deviation, each area function was attained gradually by using the method of mathematical derivation. It ensured that enhanced speech was continuous and smooth; it removed the auditory oscillation distortion; finally, combined with the Bark wavelet packets, it further improved human auditory perception. Experimental results show that the segmental SNR and PESQ (perceptual evaluation of speech quality) of the enhanced speech using this method increase effectively, compared with the existing speech enhancement algorithms based on wavelet threshold.

A fast acquisition method of DSSS signals using differential decoding and fast Fourier transform

In low earth orbit (LEO) satellite or missile communication scenarios, signals may experience extremely large Doppler shifts and have short visual time. Thus, direct sequence spread spectrum (DSSS) systems should be able to achieve acquisition in a very short time in spite of large Doppler frequencies. However, the traditional methods cannot solve it well. This work describes a new method that uses a differential decoding technique for Doppler mitigation and a batch process of FFT (fast Fourier transform) and IFFT (invert FFT) for the purpose of parallel code phase search by frequency domain correlation. After the code phase is estimated, another FFT process is carried out to search the Doppler frequency. Since both code phase and Doppler frequency domains are searched in parallel, this architecture can provide acquisition fifty times faster than conventional FFT methods. The performance in terms of the probability of detection and false alarm are also analyzed and simulated, showing that a signal-to-noise ratio (SNR) loss of 3 dB is introduced by the differential decoding. The proposed method is an efficient way to shorten the acquisition time with slightly hardware increasing.

佉卢文书所见鄯善国信差职责初探

新疆出土的佉卢文书多为反映鄯善国政治、经济的资料,在已经解读的七百多件佉卢文书中有不少文书提到鄯善国的信差。从文书内容看,信差为西域邮驿中的工作人员,他们在城邦国家之间,特别是在城邦国家内部的沟通方面作用重大。西域信差的职责不但包括将国王政令送达地方政府,而且包括将地方官员的报告书呈递至王廷,还包括对私人信件的递送和礼物、粮食的运送以及流民押送,可见鄯善国的信差对当地信息的沟通十分关键。

仙子的小信差

听说童话山的曹湾姐姐老家就在山西。那我可就是她的小老乡了。我最大的愿望就是当一个小作家，写出许许多多优美的文章。和善、稳重、大方、的我，最开心的时候就是和我的朋友们在一起了。

也谈阿古登巴其人——兼论民间“机智人物”故事的形成及性质

阿古登巴是“受压迫、受剥削的农奴的典型”,①“他的阶级立场十分坚定,斗争方向十分明确,爱憎感情十分强烈。他热爱的是农奴兄弟和一切受苦难的人,他憎恶的是那些残暴、贪婪、狡诈的反动领主、土司及奸商等少数害群之马及其丑恶行为”,他是“与格萨尔大王可以媲美”的“艺术形象”。②这是人们依据近四十年正式发表、出版的百余篇《阿古登巴的故事》所作的结论。正如其中一本故事序文所说:这仅“是我们掌握的材料中最好的一部份。但和整个阿叩(古)登巴故事比起来,只不过是大海中的一滴水。”③我们发掘各民族文化遗产,从中挑选较好的作品,推荐给广大读者,丰富社会文化生活,自然要强调现实意义,使之符合今天的政治标准和审美要求。然而,搜集、研究这种民间故事,更应重视科学的实事求是的眼光。

民国时期西藏三大高僧之一——帕邦喀活佛

拉萨北郊,色拉寺西北三里多远,有一道山坳,地名很吉祥,叫“乌都拉”,意即“宝伞山”。宝伞是藏传佛教最珍视的八吉祥物之一。山坳南坡上,天生一块其大无比的圆石,突兀雄奇,状如伏地灵龟。龟寿千年,自然又是一重祥瑞。西藏人信佛且又很讲究瑞相灵异。有这么一块风水宝地,你叫他们不建寺也不行。于是顽石上拔地而起,盖起了三层殿堂,这就是帕邦喀寺。“帕邦喀”是藏语“普隆喀”的转音,意为“顽石山”。西藏只要有了寺院,就会有许多真实的历史故事和附会的传闻圣迹。

免费而珍贵的礼物

多克是一个信差，他始终坚信自己的使命就是向人们传递快乐。因此，他的口袋里总是装着许多小纸条，上面写着一些鼓励的话。他将信件和电报送到人们手中的同时，也留给他们“今天是美好的一天”，“要笑口常开”，“别再烦恼”。

Atomic layer reversal on CeO_2 (100) surface

The structure and properties of CeO2 surfaces have been intensively studied due to their importance in a lot of surface-related applications. Since most of surface techniques probe the structure information inside the outermost surface plane, the subsurface structure information has been elusive in many studies. Using the profile imaging with aberration-corrected transmission electron microscopy, the structure information in both the outermost layer and the sublayers of the CeO2（100） surface has been obtained. In addition to the normal structures that have been reported before, where the surface is Ce-or O-terminated, a metastable surface has been discovered. In the new structure, there is an atomic layer reversal between the outermost layer and the sublayer, giving a structure with O as the outermost layer for the stoichiometry of normal Ce-terminated surface. The charge redistribution for the polarity compensation has also been changed relative to the normal surface.

Robust generalized sidelobe canceller based on eigenanalysis and a MaxSINR beamformer

A robust generalized sidelobe canceller is proposed to combat direction of arrival(DOA)mismatches.To estimate the interference-plus-noise(IPN)statistics characteristics,conventional signal of interest(SOI)extraction methods usually collect a large number of segments where only the IPN signal is active.To avoid that collection procedure,we redesign the blocking matrix structure using an eigenanalysis method to reconstruct the IPN covariance matrix from the samples.Additionally,a modified eigenanalysis reconstruction method based on the rank-one matrix assumption is proposed to achieve a higher reconstruction accuracy.The blocking matrix is obtained by incorporating the effective reconstruction into the maximum signal-to-interferenceplus-noise ratio(MaxSINR)beamformer.It can minimize the influence of signal leakage and maximize the IPN power for further noise and interference suppression.Numerical results show that the two proposed methods achieve considerable improvements in terms of the output waveform SINR and correlation coefficients with the desired signal in the presence of a DOA mismatch and a limited number of snapshots.Compared to the first proposed method,the modified one can reduce the signal distortion even further.