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Science China(Information Sciences) 2025年

作者： Di ZHAO Rui DING Bin SONG State Key Laboratory of Integrated services Networks Xidian University Hangzhou Institute of Technology Xidian University China Satellite Network group Co. Ltd.

Future 6G networks will integrate non-terrestrial communication with mobile edge computing to enable wide-area edge intelligence, providing ubiquitous communication and computation services for everyone and everything. In this paper, we introduce the intelligent cloud-edge-device architecture into low Earth orbit (LEO) satellite-supported remote Internet of Things(IoT) networks to facilitate latency-sensitive and compute-intensive IoT applications. However, the dynamic spatio-temporal characteristics inherent in LEO satellite networks, such as the high volatility of task traffic and the high mobility of space nodes, pose severe challenges. For efficient task execution, we investigate the joint optimization of cross-region task offloading and cross-domain resource allocation, and innovatively propose a spatio-temporal attention-based proximal policy optimization(STA-PPO) algorithm. Specifically, the temporal attention-based actor network analyzes the timing dependencies of task arrival and makes time-variant decisions. Simultaneously, the spatial attention-based critic network captures the spatial variations of satellite motion and evaluates the topology-related value. We verify the effectiveness of the cloud-edge-device collaboration through extensive simulations. Numerical results demonstrate that the STA-PPO algorithm outperforms benchmarks, showing the lowest system delay and the highest link throughput.

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Research on Gardening Status and Development Prospect of China Facilities Horticulture

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International Journal of Technology Management 2014年第10期 85-87页

作者： Liang Hu logistics services group Jiujiang University

Horticulture refers to the producing of horticultural plants in unsuitable season （cold or hot）, the use of keeping heat, preventing cold or keeping cool, rain facilities and equipment, to artificially create a suitable micro climate horticultural crop growth environment, not or less affected by natural seasons conduct horticultural crop production, which is known as horticulture. It Simply covers facilities include a variety of hotbed, cooling bed, a small shed, shade avoidance, shade, shade cover, etc.; ordinary protection facilities usually refers to plastic greenhouses, plastic shed and Greenhouse; modem greenhouse, usually refers to capable of temperature and humidity, environmental conditions, fertilizer, gas and other automatic control of single buildings or greenhouse.

关键词： Horticulture Insulation Cultivation

Effects of core position of locally resonant scatterers on low-frequency acoustic absorption in viscoelastic panel

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Chinese Physics B 2015年第8期24卷 398-403页

作者：钟杰温激鸿赵宏刚尹剑飞杨海滨 Vibration and Acoustics Research group Laboratory of Science and Technology on Integrated Logistics SupportNational University of Defense Technology

Locally resonant sonic materials, due to their ability to control the propagation of low-frequency elastic waves, have become a promising option for underwater sound absorption materials. In this paper, the finite element method is used to investigate the absorption characteristics of a viscoelastic panel periodically embedded with a type of infinite-long noncoaxially cylindrical locally resonant scatterers(LRSs). The effect of the core position in the coating layer of the LRS on the low-frequency(500 Hz–3000 Hz) sound absorption property is investigated. With increasing the longitudinal core eccentricity e, there occur few changes in the absorptance at the frequencies below 1500 Hz, however, the absorptance above 1500 Hz becomes gradually better and the valid absorption(with absorptance above 0.8) frequency band(VAFB)of the viscoelastic panel becomes accordingly broader. The absorption mechanism is revealed by using the displacement field maps of the viscoelastic panel and the steel slab. The results show two typical resonance modes. One is the overall resonance mode(ORM) caused by steel backing, and the other is the core resonance mode(CRM) caused by LRS. The absorptance of the viscoelastic panel by ORM is induced mainly by the vibration of the steel slab and affected little by core position. On the contrary, with increasing the core eccentricity, the CRM shifts toward high frequency band and decouples with the ORM, leading to two separate absorption peaks and the broadened VAFB of the panel.

关键词： finite element method non-coaxially cylindrical locally resonant scatterers core position sound absorption

Flexural wave band-gaps in phononic metamaterial beam with hybrid shunting circuits

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Chinese Physics B 2015年第3期24卷 269-274页

作者：张浩温激鸿陈圣兵王刚温熙森 Vibration and Acoustics Research group Laboratory of Science and Technology on Integrated Logistics SupportCollege of Mechatronics and AutomationNational University of Defense Technology

Periodic arrays of hybrid-shunted piezoelectric patches are used to control the band-gaps of phononic metamaterial beams. Passive resistive-inductive （RL） shunting circuits can produce a narrow resonant band-gap （RG）, and active negative capacitive （NC） shunting circuits can broaden the Bragg band-gaps （BGs）. In this article, active NC shunting circuits and passive resonant RL shunting circuits are connected to the same piezoelectric patches in parallel, which are usually called hybrid shunting circuits, to control the location and the extent of the band-gaps. A super-wide coupled band-gap is generated when the coupling between RG and the BG occurs. The attenuation constant of the infinite periodic structure is predicted by the transfer matrix method, which is compared with the vibration transmittance of a finite periodic structure calculated by the finite element method. Numerical results show that the hybrid-shunting circuits can make the band-gaps wider by appropriately selecting the inductances, negative capacitances, and resistances.

关键词： phononic metamaterial band-gap hybrid shunting circuits flexural wave

Acoustic anechoic layers with singly periodic array of scatterers: Computational methods, absorption mechanisms, and optimal design

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Chinese Physics B 2014年第10期23卷 283-291页

作者：杨海滨李岳赵宏刚温激鸿温熙森 Vibration and Acoustics Research group Laboratory of Science and Technology on Integrated Logistics SupportCollege of Mechatronics and Automation National University of Defense Technology

The acoustic properties of anechoic layers with a singly periodic array of cylindrical scatterers are investigated. A method combined plane wave expansion and finite element analysis is extended for out-of-plane incidence. The reflection characteristics of the anechoic layers with cavities and locally resonant scatterers are discussed. The backing is a steel plate followed by an air half space. Under this approximate zero transmission backing condition, the reflection reduction is induced by the absorption enhancement. The absorption mechanism is explained by the scattering/absorption cross section of the isolated scatterer. Three types of resonant modes which can induce efficient absorption are revealed. Due to the fact that the frequencies of the resonant modes are related to the size of the scatterers, anechoic layers with scatterers of mixed size can broaden the absorption band. A genetic optimization algorithm is adopted to design the anechoic layer with scatterers of mixed size at a desired frequency band from 2 kHz to l0 kHz for normal incidence, and the influence of the incident angle is also discussed.

关键词： acoustic anechoic layer resonant scattering resonant absorption singly periodic mixed size

Analysis of underwater decoupling properties of a locally resonant acoustic metamaterial coating

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Chinese Physics B 2016年第2期25卷 221-228页

作者：黄凌志肖勇温激鸿杨海滨温熙森 Vibration and Acoustics Research group Laboratory of Science and Technology on Integrated Logistics Support College of Mechatronic Engineering and AutomationNational University of Defense Technology

This paper presents a semi-analytical solution for the vibration and sound radiation of a semi-infinite plate covered by a decoupling layer consisting of locally resonant acoustic metamaterial. Formulations are derived based on a combination use of effective medium theory and the theory of elasticity for the decoupling material. Theoretical results show good agree- ments between the method developed in this paper and the conventional finite element method （FEM）, but the method of this paper is more efficient than FEM. Numerical results also show that system with acoustic metamaterial decoupling layer exhibits significant noise reduction performance at the local resonance frequency of the acoustic metamaterial, and such performance can be ascribed to the vibration suppression of the base plate. It is demonstrated that the effective density of acoustic metamaterial decoupling layer has a great influence on the mechanical impedance of the system. Furthermore, the resonance frequency of locally resonant structure can be effectively predicted by a simple model, and it can be significantly affected by the material properties of the locally resonant structure.

关键词： locally resonant decoupling mechanism underwater sound radiation

Meta-analysis of probiotics for the treatment of irritable bowel syndrome

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World Journal of Gastroenterology 2008年第17期14卷 2650-2661页

作者： Lynne V McFarland Sascha Dublin Department of Health services Research and Development group Health Center for Health Studies

Irritable bowel syndrome （IBS） is a chronic condition affecting 3%-25% of the general population. As no curative treatment is available, therapy is aimed at reducing symptoms, often with little success. Because alteration of the normal intestinal microflora has been observed in IBS, probiotics （beneficial microbes taken to improve health） may be useful in reducing symptoms. This paper systematically reviews randomized, controlled, blinded bials of probiotics for the treatment of IBS and synthesizes data on efficacy across trials of adequate quality. Pubr4ed, Medline, Google Scholar, NIH registry of clinical trials, metaRegister, and the Cochrane Central Register of Controlled Trials were searched from 1982-2007. We also conducted secondary searches of reference lists, reviews, commentaries, relevant articles on associated diseases, books and meeting abstracts. Twenty trials with 23 probiotic treatment arms and a total of 1404 subjects met inclusion criteria. Probiotic use was associated with improvement in global IBS symptoms compared to placebo [pooled relative risk （RRpooled） 0.77, 95% confidence interval （95% CI） 0.62-0.94]. Probiotics were also associated with less abdominal pain compared to placebo [RRpooled = 0.78 （0.69-0.88）]. Too few studies reported data on other IBS symptoms or on specific probiotic strains to allow estimation of a pooled RR. While our analyses suggest that probiotic use may be associated with improvement in IBS symptoms compared to placebo, these results should be interpreted with caution, given the methodological limitations of contributing studies. Probiotics warrant further study as a potential therapy for IBS.

关键词： Probiotics Meta-analysis Irritable bowel syndrome

Optimization of Control Loops and Operating Parameters for Three-Phase Separators Used in Oilfield Central Processing Facilities

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Fluid Dynamics & Materials Processing 2023年第3期19卷 635-649页

作者： Zhenfeng Li Yaqiao Li Guangjun Wei Anton Oilfield services(group) Ltd.Beijing100102China

In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing *** considered main influencing factors include(but are not limited to)the typical size of oil and water droplets,the residence time and temperature of fluid and the dosage of *** the“Specification for Oil and Gas Separators”as a basis,the control loops and operating parameters of each separator are optimized Considering the Halfaya Oilfield as a testbed,it is shown that the proposed approach can lead to good results in the production stage.

关键词： Distributed control system(DCS) three-phase separator control loop operating parameter

Reversibility of diabetes mellitus: Narrative review of the evidence

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World Journal of Diabetes 2018年第7期9卷 127-131页

作者： Gary Yee Ang Health services and Outcomes Research National Healthcare Group

The global disease burden of diabetes mellitus is high. It is well-established that prediabetes is reversible but it is unclear whether diabetes is reversible once it has been diagnosed. The objective of this narrative review is to review the evidence of reversibility of diabetes me-llitus and stimulate interest in prolonged remission as a treatment target. The current evidence for bariatric surgery is stronger than intensive medical management and the evidence is stronger for type 2 diabetes pa-tients compared with type 1 diabetes patients. It is also unclear whether non obese diabetes patients would benefit from such interventions and the duration of diabetes before diabetes become irreversible. Further research is needed in this area especially with regards to the subgroup of diabetes patient who will benefit from these interventions and the long term safety and efficacy remains unknown especially with intensive me-dical management.

关键词： Diabetes Reversibility Remission Bariatric surgery Obesity

Design of the Coordinate Transformation Function for Cylindrical Acoustic Cloaks with a Quantity of Discrete Layers

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Chinese Physics Letters 2014年第9期31卷 91-94页

作者：蔡力温激鸿郁殿龙陆智淼温熙森 Vibration and Acoustics Research group Science and Technology on Integrated Logistics Support Laboratory College of Mechatronic Engineering and Automation National University of Defense Technology Changsha 410073

Acoustic cloak based on coordinate transformation is of great topical interest and has promise in potential appli- cations such as sound transparency and insulation. The frequency response of acoustic cloaks with a quantity of discrete homogeneous layers is analyzed by the acoustic scattering theory. The effect of coordinate transforma- tion function on the acoustic total scattering cross section is discussed to achieve low scattering with only a few layers of anisotropic metamaterials. Also, the physics of acoustic wave interaction with the interfaces between the discrete layers inside the cloak shell is discussed. These results provide a better way of designing a multilayered acoustic cloak with fewer layers.

关键词： Frequency response