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Video quality based link adaptation for low latency video transmission over WLANs

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 847-856页

作者： ferr pierre DOUFEXI Angela CHUNG-HOW James NIX Andrew BULL David University of Bristol Department of Electrical and Electronic Engineering Centre for Communications Research Bristol BS8 1UB UK ProVision Communication Technologies Bristol BS4 4EU UK

Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes, each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in the literature either maximise the error-free data throughput based on channel conditions or are based on the number of failed transmissions. However, these algo- rithms do not take into account the content of the data stream and strongly rely on the use of Automatic Repeat Requests (ARQs). Low latency video applications such as real-time video transmission may require no retransmission, or only a limited number of retrans- missions. Moreover, completely error-free communication is not essential, especially if robust video compression techniques are applied. In such scenarios, improved decoded video quality can be obtained with a video stream transmitted at a higher bit rate using a higher link speed but with some degree of transmission error, rather than an error-free video stream at a lower bit rate using a lower link speed. In this work, we investigate a link adaptation scheme that improves the Quality of Service (QoS) for video transmission, based on the overall received video quality (Peak Signal to Noise Ratio, PSNR), rather than by maximising the error-free throughput. We also study a practical link adaptation approach that uses PER thresholds at the PHY layer. An empirical study showed that thresholds for switching from one mode to another are much lower (almost error free) than those currently used by throughput based schemes. We show that traditional link adaptation strategies are not appropriate for real-time video transmission with no retransmis- sion. Simulation results using the H.264 video compression standard over IEEE 802.11a are presented.

关键词： Link adaptation Wireless LAN Video quality Peak Signal to Noise Ratio (PSNR) Packet Error Rate (PER)

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Cavity optomechanics with directionally squeezed light

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 181-182页

作者： pierre Meystre Department of Physics and College of Optical Sciences University of ArizonaTucson 85721USA

It is well understood that the Heisenberg uncertainty principle imposes a fundamental limit on the precision of quantum *** way to get around this difficulty is to exploit quantum states that minimize the uncertainty on the observable of interest,increasing in the process the uncertainty on the conjugate *** states of the electromagnetic field.

关键词： field observable quantum

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Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins

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Journal of Renewable Materials 2024年第3期12卷 397-425页

作者： Antonio Pizzi Marie-pierre Laborie Zeki Candan LERMAB University of LorraineFaculty of SciencesBlvd des AiguillettesNancy54000France Chair of Forest Biomaterials Institute of Earth and Environmental SciencesUniversity of FreiburgFreiburgGermany Freiburg Materials Research Center Alberst Ludwig University of FreiburgFreiburg79104Germany Department of Forest Products Engineering Faculty of ForestryIstanbul UniversitySariyerIstanbul34473Turkey

Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based *** are a definite class of sustainable materials of the forestry *** have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several *** review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and *** constitutes a basic but essential summary of what is necessary to know of these sustainable *** doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.

关键词： Tannins flavonoids sources extraction methods analysis methods

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Immunobiodiversity:Conserved and specific immunity across land plants and beyond

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Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel Karima El Mahboubi Christophe Jacquet pierre-Marc Delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and ***,angiosperms are only one of five major land plant *** a whole lineage,plants also include algal *** these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given *** this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the *** angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense *** diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond *** basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune *** rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to *** propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

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Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

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Geodesy and Geodynamics 2024年第1期15卷 13-26页

作者： Xianjie Li Jean-pierre Barriot Bernard Ducarme Marania Hopuare Yidong Lou Geodesy Observatory of Tahiti University of French PolynesiaFaa'a 98702French Polynesia Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)1348 Louvain-la-NeuveBelgium GNSS Research Center Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same *** verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good *** obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/*** absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/*** discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.

关键词： GPS Tide gauges Sea level changes Vertical land motion

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Use of DREAM to assess relative risks of presence of pharmaceuticals and personal care products from a wastewater treatment plant

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 91-104页

作者： Daniela M.Pampanin Daniel Schlenk Matteo Vitale pierre Liboureau Magne O Sydnes Department of Chemistry Bioscience and Environmental EngineeringUniversity of StavangerStavanger 224021Norway Department of Environmental Sciences University of California RiversideRiversideCA 92521USA

Concerns related to environmental risks associated with pharmaceuticals and personal care products(PPCPs)have led researchers to seek methods for assessing and monitoring these contaminants in the aquatic *** and validating risk assessment tools that can evaluate ecological concerns and risks associated with PPCPs is ***,the suitability of a dose-related risk and effect assessment model,which estimates predicted environmental concentrations and allowed comparisons with predicted no effect concentrations determined,in combination with in vitro analyses of the whole effluent toxicity,was verified for the characterization of a PPCP *** of the most utilized PPCPs in Norway were measured in influent and effluent samples and used to parameterize the fate *** than 90%removal was attained for 12 out of 22 detected *** was not dependent on the class or the concentration of the specific substance and varied between 12%and 100%.The PPCPs detected in the discharged wastewater were utilized to assess individual contributions to the risk of the effluent,and no risk was identified for the targeted 30 *** simulations provided valuable information regarding the discharge plume distribution over time,which can aid planning of future environmental monitoring ***(using fish liver cells,PLHC-1)were used for assessing overall effluent toxicity,through cell viability,production of reactive oxygen species,and ethoxyresorufin-O-deethylase(EROD)*** present study may allow regulators to use risk-based strategies over removal criteria for monitoring studies and confirms the importance to take PPCP contamination into consideration when establishing environmental regulations.

关键词： Pharmaceuticals Wastewater effluent Ciprofloxacin Metoprolol Amitriptyline Carbamazepine Modelling Risk assessment Monitoring

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Prediction of net energy of feeds for broiler chickens

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Animal Nutrition 2024年第1期16卷 241-250页

作者： Aye-Cho Tay-Zar Manoosak Wongphatcharachai Pairat Srichana pierre-André Geraert Jean Noblet Charoen Pokphand Foods Public Company Limited(CPF) BangkokThailand Adisseo France S.A.S. AntonyFrance INRAE RennesFrance

Net energy(NE)enables the prediction of more accurate feed energy values by taking into account the heat increment which is approximately 25%of apparent metabolizable energy(AME)in ***,application of NE in poultry industry has not been practiced *** predict the NE values of broiler diets,23 diets were prepared by using 13 major ingredients(wheat,corn,paddy rice,broken rice,cassava pellets,full-fat soybean,soybean meal,canola meal,animal protein,rice bran,wheat bran,palm kernel meal and palm kernel oil).The diets were formulated in order to meet the birds'requirements and get a wide range of chemical compositions(on DM basis;33.6%to 55.3%for starch;20.8%to 28.4%for CP,2.7%to 10.6%for ether extract[EE]and 7.0%to 17.2%for NDF),with low correlations between these nutrients and low correlations between the inclusion levels of ingredients allowing for the calculation of robust prediction equations of energy values of diets or *** diets were fed to Ross 308 broilers raised in 12 open-circuit respiratory chambers from 18 to 23 d of age(4 birds per cage)and growth performance,diet AME content and heat production were measured,and dietary NE values were *** trial was conducted on a weekly basis with 12 diets measured each week(1per chamber),1 of the 23 diets(reference diet)being measured each *** diet was tested at least *** total,235 energy balance data values were available for the final *** performance,AME(15.3 MJ/kg DM on average)and AME/GE(79.4%on average)values were as *** NE/AME value averaged 76.6%and was negatively influenced by CP and NDF and positively by EE in connection with efficiencies of AME provided by CP,EE and starch for NE of 73%,87%and 81%,*** best prediction equation was:NE=(0.815×AME)—(0.026×CP)+(0.020×EE)—(0.024×NDF)with NE and AME as MJ/kg DM,and CP,EE and NDF as%of *** NE prediction equations from this study agree with other recently reported equation

关键词： Net energy Broiler Poultry Feed evaluation Energy system

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Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot Julien G.Moreau Jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

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Endoscopic treatment of biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants: Lessons learned from single-balloon enteroscopy-assisted ERCP

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 509-514页

作者： Rodrigo Garcés-Durán Laurent Monino pierre H Deprez Hubert Piessevaux Tom G Moreels Department of Gastroenterology and Hepatology Universitécatholique de LouvainCliniques Universitaires Saint-LucAvenue Hippocrates 101200 BrusselsBelgium

Background: Endoscopic treatment of biliopancreatic pathology is challenging due to surgically altered anatomy after Whipple's pancreaticoduodenectomy. This study aimed to evaluate the feasibility and safety of single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography(SBE-ERCP) to treat biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants. Methods: We retrospectively analyzed 106 SBE-ERCP procedures in 46 patients with Whipple's variants. Technical and clinical success rates and adverse events were evaluated. Results: Biliary SBE-ERCP was performed in 34 patients and pancreatic SBE-ERCP in 17, including 5 with both indications. From a total of 106 SBE-ERCP procedures, 76 were biliary indication with technical success rate of 68/76(90%) procedures and clinical success rate of 30/34(88%) patients. Mild adverse event rate was 8/76(11%), without serious adverse events. From a total of 106 SBE-ERCP procedures, 30 were pancreatic indication with technical success rate of 24/30(80%) procedures( P = 0.194 vs. biliary SBEERCP) and clinical success rate of 11/17(65%) patients( P = 0.016 vs. biliary SBE-ERCP). Mild adverse event rate was 6/30(20%)( P = 0.194 vs. biliary SBE-ERCP), without serious adverse events. After SBE-ERCP failure, endoscopic ultrasound-guided drainage, percutaneous drainage and redo surgery were alternative therapeutic options. Conclusions: Biliopancreatic pathology after Whipple's pancreaticoduodenectomy variants can be treated using SBE-ERCP without serious adverse events. Technical and clinical success rates are high for biliary indications, whereas clinical success rate of pancreatic indications is significantly lower. SBE-ERCP can be considered as first-line treatment option in this patient group with surgically altered anatomy.

关键词： Enteroscopy Endoscopic retrograde cholangiopancreatography Pancreaticoduodenectomy Surgically altered anatomy Whipple’s procedure

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