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学者姓名：谢启伟
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摘要 ：
基于两阶段DEA (data envelopment analysis)模型提出了两阶段DEA固定资源分配方法.首先利用两阶段DEA模型计算各个决策单元之间的效率;然后考虑各决策单元的运营模式,提出比例分摊模型,引入一系列度量按有效分摊方案集与按比例分配方案分摊的成本之间的差异的偏差变量,通过最小化偏差,得到唯一的固定资源分摊方案集;最后利用Tobit模型探究外部影响因素对决策单元效率的影响.利用上述方法对中国31个省(自治区,直辖市)参加第十二届全运会的数据进行了分析.结果表明:在整个两阶段全运会过程中,仅山东省和西藏自治区为DEA有效,且提高各地区总效率的关键在于提高其AC阶段效率;从固定...
关键词 ：
Tobit回归 Tobit回归 两阶段DEA模型 两阶段DEA模型 绩效评价 绩效评价 资源分摊 资源分摊
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| GB/T 7714 | 崔泽欣 , 王婵 , 张欣 et al. 两阶段DEA绩效评价及其分摊模型——以全运会为例 [J]. | 系统科学与数学 , 2021 , 41 (03) : 667-687 . |
| MLA | 崔泽欣 et al. "两阶段DEA绩效评价及其分摊模型——以全运会为例" . | 系统科学与数学 41 . 03 (2021) : 667-687 . |
| APA | 崔泽欣 , 王婵 , 张欣 , 谢启伟 . 两阶段DEA绩效评价及其分摊模型——以全运会为例 . | 系统科学与数学 , 2021 , 41 (03) , 667-687 . |
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摘要 ：
The majority of data envelopment analysis (DEA) models can be linearized via the classical Charnes-Cooper transformation. Nevertheless, this transformation does not apply to sum-of-fractional DEA efficiencies models, such as the secondary goal I (SG-I) cross efficiency model and the arithmetic mean two-stage network DEA model. To solve a sum-of-fractional DEA efficiencies model, we convert it into bilinear programming. Then, the obtained bilinear programming is relaxed to mixed-integer linear programming (MILP) by using a multiparametric disaggregation technique. We reveal the hidden mathematical structures of sum-of-fractional DEA efficiencies models, and propose corresponding discretization strategies to make the models more easily to be solved. Discretization of the multipliers of inputs or the DEA efficiencies in the objective function depends on the number of multipliers and decision-making units. The obtained MILP provides an upper bound for the solution and can be tightened as desired by adding binary variables. Finally, an algorithm based on MILP is developed to search for the global optimal solution. The effectiveness of the proposed method is verified by using it to solve the SG-I cross efficiency model and the arithmetic mean two-stage network DEA model. Results of the numerical applications show that the proposed approach can solve the SG-I cross efficiency model with 100 decision-making units, 3 inputs, and 3 outputs in 329.6 s. Moreover, the proposed approach obtains more accurate solutions in less time than the heuristic search procedure when solving the arithmetic mean two-stage network DEA model.
关键词 ：
Data envelopment analysis Data envelopment analysis Fractional programming Fractional programming Global optimal solution Global optimal solution Mixed-integer linear programming Mixed-integer linear programming
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| GB/T 7714 | Xie, Jianhui , Xie, Qiwei , Li, Yongjun et al. Solving data envelopment analysis models with sum-of-fractional objectives: a global optimal approach based on the multiparametric disaggregation technique [J]. | ANNALS OF OPERATIONS RESEARCH , 2021 , 304 (1-2) : 453-480 . |
| MLA | Xie, Jianhui et al. "Solving data envelopment analysis models with sum-of-fractional objectives: a global optimal approach based on the multiparametric disaggregation technique" . | ANNALS OF OPERATIONS RESEARCH 304 . 1-2 (2021) : 453-480 . |
| APA | Xie, Jianhui , Xie, Qiwei , Li, Yongjun , Liang, Liang . Solving data envelopment analysis models with sum-of-fractional objectives: a global optimal approach based on the multiparametric disaggregation technique . | ANNALS OF OPERATIONS RESEARCH , 2021 , 304 (1-2) , 453-480 . |
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摘要 ：
Electron microscopy has become the most important technique in the field of connectomics. Several methods have been proposed in the literature to tackle the problem of dense reconstruction. However, sparse reconstruction, which is a promising technique, has not been extensively studied. As a result, we develop an AI integrated system for sparse reconstruction that can automatically trace neurons with only the initial seeded masks. First, as an important part of the system for interlayer information estimation, convolutional LSTMs are employed to estimate the spatial contexts between adjacent sections. Then, the intra-slice information is obtained by a lightweight U-Net. Moreover, we employ a novel recursive training method that can significantly improve the performance. To reduce the tracing errors caused by misalignments in large-scale data, we integrate a shift estimation and correction module that effectively improves the traced neuron length. To the best of our knowledge, this is the first attempt to apply a recurrent neural network to the task of neuron tracing. In addition, our approach performs better than other state-of-the-art methods on two highly anisotropic datasets.
关键词 ：
Convolutional LSTM Convolutional LSTM Deep learning Deep learning Electron microscopy Electron microscopy Neuron tracing Neuron tracing
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| GB/T 7714 | Liu, Jing , Hong, Bei , Chen, Xi et al. An effective AI integrated system for neuron tracing on anisotropic electron microscopy volume [J]. | BIOMEDICAL SIGNAL PROCESSING AND CONTROL , 2021 , 69 . |
| MLA | Liu, Jing et al. "An effective AI integrated system for neuron tracing on anisotropic electron microscopy volume" . | BIOMEDICAL SIGNAL PROCESSING AND CONTROL 69 (2021) . |
| APA | Liu, Jing , Hong, Bei , Chen, Xi , Xie, Qiwei , Tang, Yuanyan , Han, Hua . An effective AI integrated system for neuron tracing on anisotropic electron microscopy volume . | BIOMEDICAL SIGNAL PROCESSING AND CONTROL , 2021 , 69 . |
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摘要 ：
The extant literature mainly utilized the wavelet tools and EMD-type methods to investigate linkages between different markets based on the frequency-domain information, confronting the difficulties of the wavelet basis selections and scale aliasing phenomenon. To overcome these disadvantages, the present study proposes a BEKK-GARCH-AFD approach based on the adaptive-Fourier-decomposition (AFD) to reveal the linkages between the international crude oil market and the Chinese stock market. According to the spillover effect between markets revealed by BEKK-GARCH, the proposed approach could further disclose the linkages between markets under external shocks with high-resolution information concerning market fluctuations provided by the AFD. Our empirical results demonstrate that the oil supply and demand shocks caused by external events (e.g., the strikes, the geopolitics, and the natural disasters) will put pressure on the Chinese stock market, while the combination of bullish and bearish events (e.g., the reduction of crude oil production and the shale oil boom) contributes to stabilizing the stock market.
关键词 ：
Adaptive-Fourier-decomposition (AFD) Adaptive-Fourier-decomposition (AFD) BEKK-GARCH BEKK-GARCH Oil and stock markets Oil and stock markets Structural breaks Structural breaks Time-frequency domain Time-frequency domain
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| GB/T 7714 | Xie, Qiwei , Liu, Ranran , Qian, Tao et al. Linkages between the international crude oil market and the Chinese stock market: A BEKK-GARCH-AFD approach [J]. | ENERGY ECONOMICS , 2021 , 102 . |
| MLA | Xie, Qiwei et al. "Linkages between the international crude oil market and the Chinese stock market: A BEKK-GARCH-AFD approach" . | ENERGY ECONOMICS 102 (2021) . |
| APA | Xie, Qiwei , Liu, Ranran , Qian, Tao , Li, Jingyu . Linkages between the international crude oil market and the Chinese stock market: A BEKK-GARCH-AFD approach . | ENERGY ECONOMICS , 2021 , 102 . |
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摘要 ：
In response to the limitation of classical Data Envelopment Analysis (DEA) models, the super efficiency DEA models, including Andersen and Petersen (Manag Sci 39(10): 1261-1264, 1993)'s model (hereafter called AP model) and Li et al. (Eur J Oper Res 255(3): 884-892, 2016)'s cooperative-game-based model (hereafter called L-L model), have been proposed to rank efficient decision-making units (DMUs). Although both models have been widely applied in practice, there is a paucity of research examining the performance of the two models in ranking efficient DMUs. Consequently, it is unclear how close the rankings obtained by the two models are to the "true" ones. Among the very few studies, Banker et al. (Ann Oper Res 250(1): 21-35, 2017) pointed out that the ranking performance of the AP model is unsatisfactory; Li et al. (Eur J Oper Res 255(3): 884-892, 2016) and Hinojosa et al. (Exp Syst Appl 80(9): 273-283, 2017) demonstrated the L-L model's capability of ranking efficient DMUs without addressing the ranking performance. In this study, we, thus, examine the ranking performance of the two super-efficiency models. In evaluating their performance, we carry out Monte Carlo simulations based on the well-known Cobb-Douglas production function and adopt Kendall rank correlation coefficient. Unlike Banker et al. (Ann Oper Res 250(1): 21-35, 2017), we use the rankings obtained based on the two models and the "true" ones as the basis of performance evaluation in our simulations. Moreover, we consider several types of returns to scale (RS) and study the impact of changes of some parameters on the ranking performance. In view of the importance, we also carry out additional simulations to examine the influence of technical inefficiency on the two models' ranking performance. Based on the simulation results, we conclude: (1) Under different RS, the ranking performance of the two models remains the same when changing parameters, e.g., the distribution of input variables; (2) Under different RS, when technical inefficiency (in comparison with random noise) is more important, the two models have satisfactory performance by providing rankings that are close to, or the same as, the "true" ones; (3) The L-L model has better performance than the AP model and is more robust. This is especially true when technical inefficiency is less important; (4) Under different RS, when technical inefficiency is less important, both models have unsatisfactory ranking performance; and (5) The relative importance of technical inefficiency plays an prominent role in ranking efficient DMUs.
关键词 ：
DEA DEA Monte Carlo Monte Carlo Ranking Ranking Returns to scale Returns to scale Super efficiency Super efficiency Technical inefficiency Technical inefficiency
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| GB/T 7714 | Xie, Qiwei , Zhang, Linda L. , Shang, Haichao et al. Evaluating performance of super-efficiency models in ranking efficient decision-making units based on Monte Carlo simulations [J]. | ANNALS OF OPERATIONS RESEARCH , 2021 , 305 (1-2) : 273-323 . |
| MLA | Xie, Qiwei et al. "Evaluating performance of super-efficiency models in ranking efficient decision-making units based on Monte Carlo simulations" . | ANNALS OF OPERATIONS RESEARCH 305 . 1-2 (2021) : 273-323 . |
| APA | Xie, Qiwei , Zhang, Linda L. , Shang, Haichao , Emrouznejad, Ali , Li, Yongjun . Evaluating performance of super-efficiency models in ranking efficient decision-making units based on Monte Carlo simulations . | ANNALS OF OPERATIONS RESEARCH , 2021 , 305 (1-2) , 273-323 . |
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摘要 ：
Background and Objective: Virus identification in electron microscopy (EM) images is considered as one of the front-line method in pathogen diagnosis and re-emerging infectious agents. However, the existing methods either focused on the detection of a single virus or required large amounts of manual labeling work to segment virus. In this work, we focus on the task of virus classification and propose an effective and simple method to identify different viruses. Methods: We put forward a residual mixed attention network (RMAN) for virus classification. The proposed network uses channel attention, bottom-up and top-down attention, and incorporates a residual architecture in an end-to-end training manner, which is suitable for dealing with EM virus images and reducing the burden of manual annotation. Results: We validate the proposed network through extensive experiments on a transmission electron microscopy virus image dataset. The top-1 error rate of our RMAN on 12 virus classes is 4.285%, which surpasses that of state-of-the-art networks and even human experts. In addition, the ablation study and the visualization of class activation mapping (CAM) further demonstrate the effectiveness of our method. Conclusions: The proposed automated method contributes to the development of medical virology, which provides virologists with a high-accuracy approach to recognize viruses as well as assist in the diagnosis of viruses. © 2020 Elsevier B.V.
关键词 ：
Computer viruses Computer viruses Diagnosis Diagnosis High resolution transmission electron microscopy High resolution transmission electron microscopy Viruses Viruses
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| GB/T 7714 | Xiao, Chi , Chen, Xi , Xie, Qiwei et al. Virus identification in electron microscopy images by residual mixed attention network [J]. | Computer Methods and Programs in Biomedicine , 2021 , 198 . |
| MLA | Xiao, Chi et al. "Virus identification in electron microscopy images by residual mixed attention network" . | Computer Methods and Programs in Biomedicine 198 (2021) . |
| APA | Xiao, Chi , Chen, Xi , Xie, Qiwei , Li, Guoqing , Xiao, Hao , Song, Jingdong et al. Virus identification in electron microscopy images by residual mixed attention network . | Computer Methods and Programs in Biomedicine , 2021 , 198 . |
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摘要 ：
The endoplasmic reticulum (ER) is a contiguous and complicated membrane network in eukaryotic cells, and membrane contact sites (MCSs) between the ER and other organelles perform vital cellular functions, including lipid homeostasis, metabolite exchange, calcium level regulation, and organelle division. Here, we establish a whole pipeline to reconstruct all ER, mitochondria, lipid droplets, lysosomes, peroxisomes, and nuclei by automated tape-collecting ultramicrotome scanning electron microscopy (ATUM-SEM) and deep learning techniques, which generates an unprecedented 3D model for mapping liver samples. Furthermore, the morphology of various organelles and the MCSs between the ER and other organelles are systematically analyzed. We found that the ER presents with predominantly flat cisternae and is knitted tightly all throughout the intracellular space and around other organelles. In addition, the ER has a smaller volume-to-membrane surface area ratio than other organelles, which suggests that the ER could be more suited for functions that require a large membrane surface area. Our data also indicate that ER‒mitochondria contacts are particularly abundant, especially for branched mitochondria. Our study provides 3D reconstructions of various organelles in liver samples together with important fundamental information for biochemical and functional studies in the liver.
关键词 ：
3D reconstruction 3D reconstruction ATUM-SEM ATUM-SEM deep learning deep learning ER ER liver liver MCSs MCSs
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| GB/T 7714 | Jiang Yi , Li Linlin , Chen Xi et al. Three-dimensional ATUM-SEM reconstruction and analysis of hepatic endoplasmic reticulum‒organelle interactions. [J]. | Journal of molecular cell biology , 2021 . |
| MLA | Jiang Yi et al. "Three-dimensional ATUM-SEM reconstruction and analysis of hepatic endoplasmic reticulum‒organelle interactions." . | Journal of molecular cell biology (2021) . |
| APA | Jiang Yi , Li Linlin , Chen Xi , Liu Jiazheng , Yuan Jingbin , Xie Qiwei et al. Three-dimensional ATUM-SEM reconstruction and analysis of hepatic endoplasmic reticulum‒organelle interactions. . | Journal of molecular cell biology , 2021 . |
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摘要 ：
Non-radial data envelopment analysis (DEA) models, such as the slacks-based measure (SBM) model, exert an important role in theoretical research and real applications on efficiency evaluation and improvement. However, those models maximize input and output slacks and may therefore find a rather far projection for each inefficient decision-making unit (DMU). This results in varying performance measures and inconveniences in improving the performance of inefficient DMUs. Tone (2016) proposed a new non-oriented SBM-Max model and several algorithms to overcome such limitations. However, those algorithms were computationally expensive and complicated, limiting their applications to different problems. In the present study, algorithms are proposed based on two convex hull algorithms to make a novel variation of (Tone, 2016) that is easily applicable to different problems. The proposal is based on the constant returns-toscale (CRS) assumption. The algorithms can be further extended based on other assumptions of returns to scale. The used two convex hull algorithms were the Quickhull (Qhull) algorithm and the C++ (ANSI C) implementation of the double description (CDD) algorithm. The proposed algorithms were tested on a dataset from prior literature and a real dataset of Hong Kong hospitals. The results demonstrate that the proposed algorithms are effective for finding a close projection on efficiency evaluation, resulting in improvements in DMUs.
关键词 ：
(CDD) algorithm (CDD) algorithm Convex hull algorithm Convex hull algorithm C plus plus implementation of the double description C plus plus implementation of the double description Data envelopment analysis (DEA) Data envelopment analysis (DEA) Efficient facets Efficient facets Quickhull (Qhull) algorithm Quickhull (Qhull) algorithm Slacks-based measure (SBM) Slacks-based measure (SBM)
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| GB/T 7714 | Xie, Qiwei , Zhu, Yuanchang , Shang, Haichao et al. Variations on the theme of slacks-based measure of efficiency: Convex hull-based algorithms [J]. | COMPUTERS & INDUSTRIAL ENGINEERING , 2021 , 159 . |
| MLA | Xie, Qiwei et al. "Variations on the theme of slacks-based measure of efficiency: Convex hull-based algorithms" . | COMPUTERS & INDUSTRIAL ENGINEERING 159 (2021) . |
| APA | Xie, Qiwei , Zhu, Yuanchang , Shang, Haichao , Li, Yongjun . Variations on the theme of slacks-based measure of efficiency: Convex hull-based algorithms . | COMPUTERS & INDUSTRIAL ENGINEERING , 2021 , 159 . |
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摘要 ：
Few studies have considered the information in the frequency domain to detect the structural breaks in financial markets. This paper provides a mixed model that integrates BEMD, AFD and Chow test to study the fluctuation characteristics of the soybean futures price. Due to the application of AFD, the mixed model can detect the structural breaks of the price fluctuation through obtaining the high-resolution information in the frequency domain. According to our results, in general, the soybean futures price in China is mainly determined by IMF11, followed by IMF9, IMF8 and IMF7, and there exist many structural breaks of different IMFs. Interestingly, national macro-controls have opposite effects at IMF8 and IMF11. The results show the effectiveness of the proposed mixed model for detecting structural breaks of financial markets in frequency-domain by revealing the impact of external events on the soybean futures price at multi-scales.
关键词 ：
adaptive Fourier decomposition adaptive Fourier decomposition Chow test Chow test empirical mode decomposition empirical mode decomposition Price fluctuation Price fluctuation risk management risk management
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| GB/T 7714 | Xie, Qiwei , Liu, Ranran , Li, Jingyu et al. Multi-scale analysis of influencing factors for soybean futures price risk: Adaptive Fourier decomposition mathematical model applied for the case of China [J]. | INTERNATIONAL JOURNAL OF WAVELETS MULTIRESOLUTION AND INFORMATION PROCESSING , 2021 , 19 (05) . |
| MLA | Xie, Qiwei et al. "Multi-scale analysis of influencing factors for soybean futures price risk: Adaptive Fourier decomposition mathematical model applied for the case of China" . | INTERNATIONAL JOURNAL OF WAVELETS MULTIRESOLUTION AND INFORMATION PROCESSING 19 . 05 (2021) . |
| APA | Xie, Qiwei , Liu, Ranran , Li, Jingyu , Wang, Xiaojiong . Multi-scale analysis of influencing factors for soybean futures price risk: Adaptive Fourier decomposition mathematical model applied for the case of China . | INTERNATIONAL JOURNAL OF WAVELETS MULTIRESOLUTION AND INFORMATION PROCESSING , 2021 , 19 (05) . |
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摘要 ：
This study designs a novel image encryption cryptosystem through the two-dimensional partial unwinding decomposition (2D-PUD). It consists of three stages. Firstly, a stream sequence (first part of the security key) is generated by pseudo-random number. Secondly, the plain image is decomposed into three parts by 2D-PUD: one 2D decomposition component, two 1D decomposition components, and the average intensity value of the image. Finally, the 2D decomposition component is shuffled by a generalized Arnold transform where the average intensity value is selected as second part of the security key. The diffusion scheme is subsequently applied to the scrambled image via exclusive OR operations with the randomized 1D decomposition components (third part of the security key) along rows and columns to obtain the cipher image. Due to the adaptive attribute of 2D-PUD, the generated 1D decomposition components are completely distinct for different images. In addition, we can also make them significantly different by tuning the decomposition times for the same image. Thus, the proposed algorithm is an image-content-adaptive encryption scenario that can effectively resist cryptographic attacks. Simulation results demonstrate that our proposed method has excellent encryption performance and can resist against various typical attacks, including brute force, statistical, entropy, and differential attacks. (C) 2020 Elsevier B.V. All rights reserved.
关键词 ：
Image-content-adaptive encryption Image-content-adaptive encryption Image encryption Image encryption Information security Information security Partial unwinding decomposition Partial unwinding decomposition
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| GB/T 7714 | Wu, Yongfei , Zhang, Liming , Qian, Tao et al. Content-adaptive image encryption with partial unwinding decomposition [J]. | SIGNAL PROCESSING , 2021 , 181 . |
| MLA | Wu, Yongfei et al. "Content-adaptive image encryption with partial unwinding decomposition" . | SIGNAL PROCESSING 181 (2021) . |
| APA | Wu, Yongfei , Zhang, Liming , Qian, Tao , Liu, Xilin , Xie, Qiwei . Content-adaptive image encryption with partial unwinding decomposition . | SIGNAL PROCESSING , 2021 , 181 . |
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