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Minimum Structural Similarity Distortion for Reversible Data Hiding

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Chinese Journal of Electronics 2018年第3期27卷 582-587页

作者： XU Jiajia ZHANG Weiming jiang ruiqi YU Nenghai HU Xiaocheng University of Science and Technology of China

Until now, most Reversible data hiding(RDH) techniques have been evaluated by Peak signal-tonoise ratio(PSNR), which based on Mean squared error(MSE). Unfortunately, MSE turns out to be an extremely poor measure when the purpose is to predict perceived signal fidelity or quality. The Structural similarity(SSIM)index has gained widespread popularity as an alternative motivating principle for the design of image quality measures. How to utilize the characterize of SSIM to design RDH algorithm is very critical. We propose an optimal RDH algorithm under structural similarity constraint. We deduce the metric of the structural similarity constraint,and further we prove it does not hold Non-crossing-edges(NCE) property. We construct the rate-distortion function of optimal structural similarity constraint, which is equivalent to minimize the average distortion for a given embedding rate, and then we can obtain the optimal transition probability matrix under the structural similarity constraint. Experiments show that our proposed method can be used to improve the performance of previous RDH schemes evaluated by SSIM.

关键词： Reversible data hiding Structural similarity Recursive code construction

Infrared avalanche photodiodes from bulk to 2D materials

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Light(Science & Applications) 2023年第10期12卷 2027-2052页

作者： Piotr Martyniuk Peng Wang Antoni Rogalski Yue Gu ruiqi jiang Fang Wang Weida Hu Institute of Applied Physics Military University of Technology2 Kaliskiego Street00-908WarsawPoland State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of Sciences500 Yu-Tian RoadShanghaiChina

Avalanche photodiodes (APDs) have drawn huge interest in recent years and have been extensively used in a range of fields including the most important one—optical communication systems due to their time responses and high sensitivities. This article shows the evolution and the recent development of A^(Ⅲ)B^(Ⅴ), A^(Ⅱ)B^(Ⅵ), and potential alternatives to formerly mentioned—“third wave” superlattices (SL) and two-dimensional (2D) materials infrared (IR) APDs. In the beginning, the APDs fundamental operating principle is demonstrated together with progress in architecture. It is shown that the APDs evolution has moved the device’s performance towards higher bandwidths, lower noise, and higher gain-bandwidth products. The material properties to reach both high gain and low excess noise for devices operating in different wavelength ranges were also considered showing the future progress and the research direction. More attention was paid to advances in A^(Ⅲ)B^(Ⅴ) APDs, such as AlInAsSb, which may be used in future optical communications, type-Ⅱ superlattice (T2SLs, “Ga-based” and “Ga-free”), and 2D materials-based IR APDs. The latter—atomically thin 2D materials exhibit huge potential in APDs and could be considered as an alternative material to the well-known, sophisticated, and developed A^(Ⅲ)B^(Ⅴ) APD technologies to include single-photon detection mode. That is related to the fact that conventional bulk materials APDs’ performance is restricted by reasonably high dark currents. One approach to resolve that problem seems to be implementing low-dimensional materials and structures as the APDs’ active regions. The Schottky barrier and atomic level thicknesses lead to the 2D APD dark current significant suppression. What is more, APDs can operate within visible (VIS), near-infrared (NIR)/mid-wavelength infrared range (MWIR), with a responsivity ~80 A/W, external quantum efficiency ~24.8%, gain ~10^(5) for MWIR [wavelength, λ = 4 μm, temperature, T = 10–180 K, Black Phospho

关键词： Infrared noise mentioned

High-performance violet phosphorus photodetectors with van der Waals-assisted contacts

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Science China(Physics,Mechanics & Astronomy) 2023年第9期66卷 86-93页

作者： Hao Wang Shuling Liu Peng Wang Haonan Ge Yue Chen Hailu Wang Tengfei Xu Jiaxiang Guo Yuanchen Zou Wenrui Wei ruiqi jiang Fang Wang Piotr Martyniuk Jinshui Miao Weida Hu State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China School of Physics and Photoelectric Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Institute of Applied Physics Military University of TechnologyWarsaw 00-908Poland Frontier Institute of Chip and System Fudan UniversityShanghai 200438China School of Microelectronics Shanghai UniversityShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Black phosphorus(BP) as a narrow-bandgap two-dimensional semiconductor material has been extensively studied. And the allotrope violet phosphorus(VP) exhibits wide bandgap properties extending the application in the visible light band. However,due to the Schottky barrier of metal/semiconductor contacts(M/S), further device application of VP is limited. Here, VP-based photodetectors with van der Waals-assisted contact were demonstrated, achieving quasi-Ohmic M/S contacts. The output characteristics in dark conditions show ultralow current at the pA level. And the device exhibits a high current on-off ratio of 10~5and a fast response speed of 8.4 ms. Furthermore, we constructed the first allotropic photodetector based on BP and VP heterojunction. The device maintains ultralow dark current(~ pA) while exhibiting faster carrier transport, with 945 μs response time and polarization detection capability. These results offer an effective way to study the optoelectronic properties of VP and promote the study of allotropic heterojunction devices.

关键词： violet phosphorus two-dimensional materials photodetectors Ohmic contact allotropic heterojunction

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试析知识管理在美国图书馆参考咨询服务中的应用

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图书情报知识 2005年第4期22卷 102-104,108页

作者：姜瑞其中山大学信息管理系广州510275

本文详细介绍了知识管理在美国图书馆参考咨询服务中的应用,包括专家系统、知识库、网络新闻组、数据仓库等。在此基础上,文中提出了五点建议,即把知识看作一种财产、增加对馆员的了解、重视对隐性知识的获取、重视工作过程及把知识管... 详细信息

本文详细介绍了知识管理在美国图书馆参考咨询服务中的应用,包括专家系统、知识库、网络新闻组、数据仓库等。在此基础上,文中提出了五点建议,即把知识看作一种财产、增加对馆员的了解、重视对隐性知识的获取、重视工作过程及把知识管理活动与策略和行为相联系。

关键词：知识知识管理参考咨询服务图书馆

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国外机构库发展概况

图书情报工作 2005年第11期49卷 142-145,149页

作者：姜瑞其中山大学资讯管理系广州510275

介绍机构库的资源内容和国外几个有代表性的机构库项目——DSpace联盟工程、CARL试验项目、ARNO工程;全面地分析机构库的资源内容、技术系统和管理方式,并阐明其管理系统和资源内容的提交过程;最后指出机构库的发展在给图书馆员带来机... 详细信息

介绍机构库的资源内容和国外几个有代表性的机构库项目——DSpace联盟工程、CARL试验项目、ARNO工程;全面地分析机构库的资源内容、技术系统和管理方式,并阐明其管理系统和资源内容的提交过程;最后指出机构库的发展在给图书馆员带来机遇与挑战的同时,推动图书馆管理方式的进一步完善。

关键词：机构库社区图书馆

RSS在图书馆自助式数字参考咨询服务中的应用

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情报理论与实践 2006年第1期29卷 78-81页

作者：姜瑞其中山大学资讯管理系广东510275

信息聚合和信息推送是RSS的两大基本功能。本文在介绍RSS的含义和功能的基础上,从RSS的使用方法和服务过程两个方面,重点介绍和分析了RSS在图书馆自助式数字参考咨询服务中的应用。最后作者从RSS两大功能的角度并在与BBS、Email和Chat... 详细信息

信息聚合和信息推送是RSS的两大基本功能。本文在介绍RSS的含义和功能的基础上,从RSS的使用方法和服务过程两个方面,重点介绍和分析了RSS在图书馆自助式数字参考咨询服务中的应用。最后作者从RSS两大功能的角度并在与BBS、Email和Chat在线聊天等咨询方式进行比较的基础上分析了RSS服务的自助式特征。

关键词：图书馆参考咨询应用研究/RSS

Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao jiang Zengxin Qi Huixian Zhu Kangli Shen ruiqi Liu Chenxin Fang Weiwei Lou Yifan jiang Wangrui Yuan Xin Cao Liang Chen Qianxing Zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease

Buckling of thin gel strip under swelling

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Theoretical & Applied Mechanics Letters 2017年第3期7卷 134-137页

作者： ruiqi jiang Jianliang xiao Jizhou Song Department of Engineering Mechanics Soft Matter Research Center and Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang University Hangzhou 310027 China Department of Mechanical Engineering University of Colorado Boulder CO 80309 USA

The buckling of thin gel film has attracted much attention due to its applications in the design of three- dimensional structure from two-dimensional template. We have established an analytical model to study the swelling-induced buckling of a thin gel strip with one edge clamped and the others free. The closed-form solutions for the amplitude and wavelength of the buckled shape are obtained by energy minimization of the total potential energy. The analytical results agree well with finite element analysis based on the inhomogeneous gel theory without any parameter fitting. The model provides a route to study complex postbuckling behaviors of thin gel films and guidelines to design the buckled configuration quantitatively by controlling the swelling ratio.

关键词： Thin gel film Swelling Buckling

An extendable all-in-one injection twin derivatization LC-MS/MS strategy for the absolute quantification of multiple chemical-group-based submetabolomes

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An extendable all-in-one injection twin derivatization LC-MS...