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Characteristics of Sand dune Pattern and Fluvial-aeolian Interaction in Horqin Sandy Land, Northeast Plain of China

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Chinese Geographical Science 2018年第4期28卷 624-635页

作者： du huishi WANG Zongming MAO Dehua College of Tourism and Geographical Science Jilin Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

The interaction between fluvial and aeolian processes can significantly change surface morphology of the Earth. Taking the Horqin Sandy Land as the research area and using Landsat series satellite remote sensing images, this study utilizes geomorphology and landscape ecology to monitor and analyze the aeolian geomorphology characteristics of the Horqin Sandy Land. Results show that the sand dunes of the Horqin Sandy Land are mainly distributed on alluvial plains along the banks of the mainstream and tributaries of the Western Liao River, and the sand dune types tend to simplify from west to east and from south to north. The aeolian geomorphology coverage tend to be decreasing in the past 40 years, with an average annual change rate of 0.31%. While the area of traveling dunes decreased, the area of fixed and semi-fixed dunes increased. The fractal dimensions of various types of sand dune have all remained relatively constant between 1.07 and 1.10, suggesting that they are experiencing a relatively stable evolutionary process. There is a complex interaction between fluvial and aeolian processes of the Horqin Sandy Land, which plays a central role in surface landscape molding. Sand dunes on both sides of different rivers on the Horqin Sandy Land present certain regularity and different characteristics in terms of morphology, developmental scale, and spatial pattern. There are six fluvial-aeolian interaction modes in this area: supply of sand sources by rivers for sand dune development, complete obstruction of dune migration by rivers, partial obstruction of dune migration by rivers, influence of river valleys on dune developmental types on both sides, influence of river valleys on dune developmental scale on both sides, and river diversion due to obstruction and forcing by sand dunes. This study deepens our understanding of the surface process mechanism of the interaction between fluvial and aeolian processes in semi-arid regions, and provides a basis for researches on regional landscape responses in the context of

关键词：相互作用能沙丘特征东北平原土地表面形态学 Landsat 中国

Evaluation of Spectral Scale Effects in Estimation of Vegetation Leaf Area Index Using Spectral Indices Methods

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Chinese Geographical Science 2016年第6期26卷 731-744页

作者： du huishi JIANG Hailing ZHANG Lifu MAO Dehua WANG Zongming Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of Tourism and Geographical Science Jilin Normal UniversitySiping 136000China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China

Spectral index methodology has been widely used in Leaf Area Index(LAI) retrieval at different spatial scales. There are differences in the spectral response of different remote sensors and thus spectral scale effect generated during the use of spectral indices to retrieve LAI. In this study, PROSPECT, leaf optical properties model and Scattering by Arbitrarily Inclined Layers(SAIL) model, were used to simulate canopy spectral reflectance with a bandwidth of 5 nm and a Gaussian spectral response function was employed to simulate the spectral data at six bandwidths ranging from 10 to 35 nm. Additionally, for bandwidths from 5 to 35 nm, the correlation between the spectral index and LAI, and the sensitivities of the spectral index to changes in LAI and bandwidth were analyzed. Finally, the reflectance data at six bandwidths ranging from 40 to 65 nm were used to verify the spectral scale effect generated during the use of the spectral index to retrieve LAI. Results indicate that Vegetation Index of the Universal Pattern Decomposition(VIUPD) had the highest accuracy during LAI retrieval. Followed by Normalized Difference Vegetation Index(NDVI), Modified Simple Ratio Indices(MSRI) and Triangle Vegetation Index(TVI), although the coefficient of determination R^2 was higher than 0.96, the retrieved LAI values were less than the actual value and thus lacked validity. Other spectral indices were significantly affected by the spectral scale effect with poor retrieval results. In this study, VIUPD, which exhibited a relatively good correlation and sensitivity to LAI, was less affected by the spectral scale effect and had a relatively good retrieval capability. This conclusion supports a purported feature independent of the sensor of this model and also confirms the great potential of VIUPD for retrieval of physicochemical parameters of vegetation using multi-source remote sensing data.

关键词：光谱索引植被叶区域索引放射的转移模型光谱反应规模效果

GIS Applications and Development Trends in China

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Journal of Landscape Research 2015年第1期7卷 33-34页

作者： du huishi YANG Yue SUN Hong SUN Baisheng CHENG Fuwei College of Tourism and Geographical Science Jilin Normal University Department of Geography Hebei Normal University for Nationalities

Since its conceptualization and creation in the 1960 s, Geographic Information System(GIS) has considerably developed. As a combination of traditional and modern technology, GIS has become an important part of modern management, decision-making, and command, contributing greatly to social progress and development. This article introduces the concepts of GIS, expounds on the GIS applications in China, and looks forward to developments in GIS technology in the future while reviewing the issues that GIS application development faces. GIS has evolved into an important branch of the information technology industry, with great vitality and broad development prospects.

关键词： GIS Research status Development trends

Effects of Al_(2)O_(3)-SiO_(2) Raw Material Types on Properties of Anorthite Based Insulation Refractories

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China's Refractories 2024年第1期33卷 23-27页

作者： du Juan GUO huishi YANG Jialin LI Wenfeng GUI Yanghai ZHAO Zhiqiang LIU Yingfan School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China School of Materials and Chemical Engineering Zhengzhou University of Light IndustryZhengzhou 450051China

To optimize their Al_(2)O_(3)-SiO_(2) raw materials,anorthite based insulation refractories were prepared by the in-situ sintering process combined with the foaming method after sintering at 1350℃for 3 h,using green and pollution-free kaolin,kyanite,andalusite and sillimanite as Al_(2)O_(3)-SiO_(2) raw materials,respectively,and industrial CaCO_(3) as the CaO source.Effects of Al_(2)O_(3)-SiO_(2) raw material types on the physical properties,phase composition and microstructure were investigated.The results are as follows.All samples prepared by different Al_(2)O_(3)-SiO_(2) raw materials have hexagonal flake anorthite and a small amount of mullite and corundum.Their bulk density and thermal conductivity decrease in the order of using kaolin,andalusite,kyanite and sillimanite as the Al_(2)O_(3)-SiO_(2) raw material,but their apparent porosity increases.Moreover,in the sample with kaolin,the bonding between anorthite crystals on the pore walls is closer than that of the other samples,which is conducive to increasing the cold crushing strength.The bonding between anorthite crystals on pore walls gradually decreases in the order of using kyanite,andalusite and sillimanite as the Al_(2)O_(3)-SiO_(2) raw material,thus their cold crushing strength decreases accordingly.In comprehensive consideration,the properties of the sample from kyanite are the optimal.Its apparent porosity,thermal conductivity and cold crushing strength are 84.6%,0.141 W·m^(-1)·K^(-1) and 1.89 MPa,respectively.

关键词： anorthite based insulation refractories Al_(2)O_(3)-SiO_(2)raw materials crushing strength thermal conductivity microstructure

A survey on causal inference for recommendation

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The Innovation 2024年第2期5卷 130-144页

作者： huishi Luo Fuzhen Zhuang Ruobing Xie Hengshu Zhu Deqing Wang Zhulin An Yongjun Xu Institute of Artificial Intelligence Beihang UniversityBeijing 100191China Zhongguancun Laboratory Beijing 100094China WeChat Search Application Department TencentBeijing 100080China The Career Science Laboratory BOSS ZhipinBeijing 100028China SKLSDE School of Computer ScienceBeihang UniversityBeijing 100191China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

Causal inference has recently garnered significant interest among recommender system(RS)researchers due to its ability to dissect cause-and-effect relationships and its broad applicability across multiple fields.It offers a framework to model the causality in RSs such as confounding effects and deal with counterfactual problems such as offline policy evaluation and data augmentation.Although there are already some valuable surveys on causal recommendations,they typically classify approaches based on the practical issues faced in RS,a classification that may disperse and fragment the uni-fied causal theories.Considering RS researchers’unfamiliarity with causality,it is necessary yet challenging to comprehensively review relevant studies from a coherent causal theoretical perspective,thereby facilitating a deeper integration of causal inference in RS.This survey provides a systematic review of up-to-date papers in this area from a causal theory standpoint and traces the evolutionary development of RS methods within the same causal strategy.First,we introduce the fundamental concepts of causal inference as the basis of the following review.Subsequently,we propose a novel theory-driven taxonomy,categorizing existing methods based on the causal theory employed,namely those based on the potential outcome framework,the structural causal model,and general counterfactuals.The review then delves into the technical details of how existing methods apply causal inference to address particular recommender issues.Finally,we highlight some promising directions for future research in this field.Representative papers and open-source resources will be progressively available at https://***/Chrissie-Law/Causal-Inference-forRecommendation.

关键词： survey details causal

Dimethylamine oxalate manipulating CsPbI_(3) perovskite film crystallization process for high efficiency carbon electrode based perovskite solar cells

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Journal of Energy Chemistry 2024年第6期93卷 221-228,I0006页

作者： Wenran Wang Xin Peng Jianxin Zhang Jiage Lin Rong Huang Guizhi Zhang huishi Guo Zhenxiao Pan Xinhua Zhong Huashang Rao Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and EnergySouth China Agricultural UniversityGuangzhou 510642GuangdongChina College of Chemistry and Civil Engineering Shaoguan UniversityShaoguan 512005GuangdongChina Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Resources in Northern Region Shaoguan UniversityShaoguan 512005GuangdongChina

Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as an efficient additive in manipulating the crystallization process of CsPbI_(3) perovskite films.On one hand,oxalate serves as the precipitator that facilitates the nucleation process of intermediate.The larger size of intermediate is conductive to the larger size and smaller grain boundaries of resultant perovskite.On the other hand,in subsequent annealing process,the phase conversion and growth process of transient perovskite can be decelerated due to the strong interactions of oxalate with both dimethylamine cation(DMA^(+))and Pb^(2+).due to the optimized crystallization kinetics,the morphology and quality of CsPbI_(3) perovskite films are comprehensively improved with lower defect concentrations,and charge recombination loss is effectively suppressed.Benefiting from the optimized crystal quality of perovskite films,the carbon electrode-based CsPbI_(3) PSCs exhibit a champion efficiency of 18.48%.This represents one of the highest levels among all hole transport layer-free inorganic perovskite solar cells.

关键词： Solar cells Perovskite CsPbI_(3) Carbon electrodes Oxalate

A Practical Regular LDPC Coded Scheme for Physical-Layer Information Security

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China Communications 2024年第5期21卷 190-201页

作者： du Junyi CETC Key Laboratory of Avionic Information System Southwest China Institute of Electronic TechnologyChengdu 610036China

In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured LDPC coded scheme,where the information bits in a codeword are punctured and only the parity check bits are transmitted to the receiver.We further propose a notion of check node type distribution and derive multi-edge type extrinsic information transfer functions to estimate the security performance,instead of the well-known weak metric bit error rate.We optimize the check node type distribution in terms of the signal-to-noise ratio(SNR)gap and modify the progressive edge growth algorithm to design finite-length codes.Numerical results show that our proposed scheme can achieve a lower computational complexity and a smaller security gap,compared to the existing scrambling and puncturing schemes.

关键词： extrinsic information transfer function physical layer scheme secure open channel security gap

Early diagnosis and management of neonatal sepsis:a perspective

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World Journal of Pediatrics 2024年第4期20卷 303-306页

作者： Li‑Zhong du Neonatal Intensive Care Unit Children’s Hospital Zhejiang University School of MedicineNational Clinical Research Center for Child Health3333 Binsheng RoadHangzhou 310052China

Neonatal sepsis is an illness caused by bloodstream bacteria or fungal infections that affect newborn infants under 28 days of age.It stands as a significant contributor to morbidity and mortality in neonatal intensive care units(NICUs).With the improved survival rates of very low-birth-weight or extremely premature infants,a growing number of these vulnerable infants are receiving intensive care and undergoing invasive procedures,making nosocomial infections a persistent challenge in NICUs.The mortality rate associated with neonatal sepsis varies depending on factors such as birth weight,gestational age,and other co-morbidities.It can also lead to a range of long-term health consequences,including neurodevelopmental disabilities like cerebral palsy,visual or hearing impairments,and cognitive problems.Furthermore,neonatal sepsis is linked to various adverse outcomes,including respiratory complications,bronchopulmonary dysplasia,nutritional and growth issues,and immunological dysfunction[1].due to its atypical clinical presentation and the low rate of specific diagnostic indicators,such as a positive blood culture,accurately diagnosing neonatal sepsis is challenging.Consequently,the appropriateness of antibiotic treatment is often a matter of controversy.

关键词： neonatal mortality diagnosis

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi du Shihao Tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis purpose.In this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture reconstruction.Furthermore,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model T-GAN.In comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)