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法语学习 2002年第4期 35-37页

作者： francis démier

deterministic approaches for noncoherent communicationswith chaotic carriers

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Journal of Systems Engineering and Electronics 2005年第2期16卷 253-257页

作者： LiuXiongying QiuShuisheng francis.C.M.Lau CollegeofElectronicandInformationEngineering SouthChinaUniversityofTechnologyGuangzhou510640P.R.China departmentofElectronicandInformationEngineering HongkongPolytechnicUniversityHongkongP.R.China

Two problems are proposed. The first one is the noise decontamination of chaotic carriers using a deterministic approach to reconstruct pseudo trajectories, the second is the design of communications schemes with chaotic carriers. After presenting our deterministic noise decontamination algorithm, conventional chaos shift keying (CSK) communication system is applied. The difference of Euclidean distance between noisy trajectory and decontaminated trajectory in phase space could be utilized to non-coherently detect the sent symbol simply and effectively. It is shown that this detection method can achieve the bit error rate performance comparable to other non-coherent systems.

关键词： gradient descent reconstruction chaotic communications noncoherent detection.

Impact of a Phosphate Amendment on the Environmental Availability and Phytoavailability of Cd and Pb in Moderately and Highly Carbonated Kitchen Garden Soils

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Pedosphere 2017年第3期27卷 588-605页

作者： Christophe WATERLOT Christelle PRUVOT Franck MAROT francis dOUAY Yncréa Hauts-de-France Laboratoire Génie Civil et géo Environnement (LGCgE) Agence de l’Environnement et de la Matrise de l’Energie (AdEME) Direction Villes et Territoires Durables Services Friches Urbaines et Sites Pollués

The behaviour of metals mainly depends on soil p H, carbonate contents and contamination level, which should be considered for the management of contaminated soils. In this study, kitchen garden topsoils(0–25 cm) were sampled from the area around three smelters in France, with different Cd and Pb contamination levels. Effect of a phosphate amendment(a mixture of diammonium phosphate and hydroxyapatite) on the environmental availability and phytoavailability of Cd and Pb was evaluated by different chemical extractions and cultivating lettuce(Lactuca sativa L.), respectively. Changes in the distribution of Cd and Pb were found in most contaminated soils after phosphate amendment. An increase of Cd and Pb in the residual phase was highlighted in almost all carbonated contaminated soils, whereas a decrease of Pb in the exchangeable, water and acid-soluble phase was observed in most contaminated soils with the lowest carbonate contents. The concentrations of extractable Cd and Pb using calcium chloride and acetic and citric acids generally decreased after the soil amendment. Lettuces grown on amended soils were acceptable for human consumption as regard to Pb concentration. In contrast, some lettuces were unacceptable for human consumption, since the concentrations of Cd in the leaves were higher than the European legislation limit. Surprisingly, in carbonated soils with very low concentration of Cd, the Cd concentrations in lettuce reached up to the European legislation limit, making the lettuce unacceptable for human *** study highlighted the fact that the total metal concentration in soils does not always allow to predict the metal accumulation in the edible parts of vegetables in order to make a judgement about their acceptability or unacceptability for human consumption.

关键词： chemical amendment contamination immobilisation lettuce metal urban soil

Feasibility analysis of WdM links for radar applications

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defence Technology（防务技术） 2015年第1期11卷 76-84页

作者： d.MEENA FREdY francis K.T.SARATH E.dIPIN T.SRINIVAS Applied Photonics Lab ECE Department Indian Institute of Science(IISc) Electronics and Radar development Establishment (LRdE) DRDO(Ministry of Defence) Bangalore India Model Engineering College Thrikkakara Cochin India

Active phased array antennas enhances the performance of modern radars by using multiple low power transmit/receive modules in place of a high power transmitter in conventional radars. Fully distributed phased array radars demand the distribution of various signals in radio frequency(RF) and digital domain for real time operation. This is normally achieved through complex and bulky coaxial distribution networks. In this work, we intend to tap the inherent advantages of fiber links with wavelength division multiplexed(WdM) technology and a feasibility study to adapt these links for radar applications is carried out. This is done by analysing various parameters like amplitude, delay, frequency and phase variation response of various radar waveforms over WdM links. This also includes performance evaluation of non-linear frequency modulation(NLFM) signals, known for better signal to noise ratio(SNR) to specific side lobe levels. NLFM waveforms are further analysed using pulse compression(PC) technique. Link evaluation is also carried out using a standard simulation environment and is then experimentally verified with other waveforms like RF continuous wave(CW), pulsed RF and digital signals. Synchronization signals are generated from this variable duty cycle digital signals during real time radar operation. during evaluation of digital signals, variable transient effects for different duty cycles are observed from an amplifier configuration. A suppression method is proposed to eliminate this transient effects. Further, the link delay response is investigated using different lengths of fiber spools. It can be inferred from the experimental results that WdM links are capable of handling various signals significant to radar applications.

关键词： WdM Radar RF over fiber EdFA transient delay CW Pulsed CW NLFM

Review of applying X-ray computed tomography for imaging soil-root physical and biological processes

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 1-14页

作者： francis Kumi Mao Hanping Hu Jianping Ikram Ullah Key Laboratory of Modern Agricultural Equipment and Technology Ministry of Education and Jiangsu ProvinceJiangsu UniversityZhenjiang 212013China department of Agricultural Engineering University of Cape CoastCape CoastGhana

Root growth process in soils has long been a matter of interest to soil and plant *** the opaque nature of the soil has been a barrier to most research attempts aimed at unraveling the full root-soil *** traditional method of separating the roots from the growth media which is common practice tends to be destructive and defeats the purpose of such *** is ineffective in monitoring the interactions within the soil medium and as a result,a fast non-destructive technique is ***,with computing and technological advancements,X-ray computed tomography(CT)has been found to be capable of meeting this need by imaging the processes which are of interest to *** the past three-four decades,the applications of the technology for imaging soil-root studies have attracted the researchers’widespread interests and the future looks more *** purpose of this review is to present an overview of CT applications in imaging root-soil *** main focus is on the use of soil-root interface researches and the way forward for such non-destructive analyses.

关键词： computed tomography soil root imaging non-destructive interactions

Traditional knowledge in HIV/AIdS treatment and prevention program in northern Uganda

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Family Medicine and Community Health 2016年第1期4卷 46-52页

作者： francis Adyanga Akena University of South Africa(UNISA) P.O.Box 3920003

Uganda’s health care sector is choking with various challenges,such as poor physical infrastructure,inadequate professionals to run the few existing health centers,poor culture of adherence to professional ethical standards by some health care practitioners,shortages of medicines in most government hospitals/health centers,and *** of the challenges are more endemic in rural *** is on the above premise that this article discusses some of the challenges that health centers face in provision of care to the increasing number of HIV/AIdS patients in hard-to-reach rural communities in northern Uganda and the implications of such challenges on the ***’s success in the fight against HIV/AIdS in the early 1990s was globally applauded because of its aggressive grassroots behavioral change crusades aimed at reducing the number of sexual *** success inspired a wave of financial aid programs from the US government to fight the disease across the developing ***,the success was short-lived as the rate of HIV/AIdS infection in Uganda is currently rising,with the health care system struggling to provide care for the ballooning number of *** contribute to the curtailing cases of new infections,this article discuses the integration of the traditional authority and knowledge system in the national HIV/AIdS care and prevention program along with the biomedical approach currently being used.

关键词： Traditional knowledge HIV/AIdS interventions professional ethics voluntary medical male circumcision

Aphidophagous guilds on nettle （Urtica dioica） strips close to fields of green pea, rape and wheat

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Insect Science 2007年第5期14卷 419-424页

作者： AMMAR ALHMEdI ERIC HAUBRUGE BERNARd BOdSON FREdERIC francis Functional and Evolutionary Entomology Experimental Farm Gembloux Agricultural University Gembloux Belgium

The common nettle （Urtica dioica L.） is a perennial and cosmopolitan plant species and is known to be the source of food for a great diversity of insects. To understand the importance of the nettle in agro-ecosystems, a field experiment was carried out in an experimental farm at Gembloux （Belgium） to study the effect of nettle margin strips on aphid and aphidophagous populations in close field crops, namely wheat （Triticum aestivum L.）, green pea （Pisum sativum L.） and rape （Brassicae napus L.）. The aphids and related beneficial populations were weekly assessed, from March to August 2005, by visual observations in two plots per field crop. A higher abundance of aphidophagous beneficials was collected in nettle strips when compared to the field crops. Particularly, the presence of predatory anthocorids, mirids and green lacewings was observed on nettle only. Nevertheless, the most abundant aphid predatory family, the Coccinellidae, was distributed in both environments, in nettle strips and in crop fields. The field margin supported a significantly higher density ofHarmonia axyridis than the field crops. In contrast, the field crops, green pea particularly, supported a higher density of Coccinella septempunctata. The distribution of the aphidophagous species, mainly the ladybirds, was discussed in relation to the host plant and related aphid species and their potential effect on integrated pest management.

关键词： Aphidophagous ladybirds beneficials insect diversity nettle wheat greenpea rape margin strips integrated pest management Microlophium camosum Acyrthosiphonpisum Sitobion avenae

Optimization of enhanced weathering networks with alternative transportation modes

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Carbon Resources Conversion 2022年第2期5卷 167-176页

作者： Raymond R.Tan Beatriz A.Belmonte Michael francis d.Benjamin Viknesh Andiappan Kathleen B.Aviso department of Chemical Engineering De La Salle University2401 Taft Avenue0922 ManilaPhilippines Research Center for the Natural and Applied Sciences/department of Chemical Engineering University of Santo TomasEspana Blvd.1015 ManilaPhilippines School of Engineering and Physical Sciences Heriot-Watt University Malaysia62200PutrajayaWilayah Persekutuan PutrajayaMalaysia Faculty of Engineering Computing and ScienceSwinburne University of TechnologyJalan Simpang Tiga93350KuchingSarawakMalaysia

Enhanced weathering of alkaline rocks and minerals is a negative emissions technology (NET) that is potentiallyscalable to deliver gigaton-level carbon dioxide removal (CdR) for climate change mitigation. This techniquerelies on the acceleration of naturally occurring weathering reactions with water and carbon dioxide by reducingthese substances into a fine powder with high specific surface area. The ex situ enhanced weathering processchain consists of the acquisition of suitable natural or synthetic materials, grinding to a fine particle size,transportation, and application on suitable sites. Future enhanced weathering systems can be envisioned assupply chain-like networks which have to be optimized to deliver maximum CdR given physical *** is a notable research gap in the literature on decision support for such systems. To address this gap, amixed integer linear programming (MILP) model is developed in this work to optimize enhanced weatheringnetworks for CdR. The model also incorporates the availability of multiple transportation options and constraintson network topology. Two test cases are used to demonstrate the model capability to determine optimal andnear-optimal networks. The top ten solutions in these two scenarios yield total CdR levels of 3.4316–3.4363 Mtand 15.27017–15.27960 Mt.

关键词： Process integration Optimization Mathematical programming Carbon drawdown Carbon management network decarbonization

Population genetic structure of Sitobion miscanthi in China

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Journal of Integrative Agriculture 2022年第1期21卷 178-187页

作者： SUN Jing-xuan LI Qian TAN Xiao-ling FAN Jia ZHANG Yong QIN Yao-guo Frédéric francis CHEN Ju-lian State Key Laboratory for Biology of Plant diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China department of Functional and Evolutionary Entomology Gembloux Agro-Bio TechUniversity of LiègeGembloux 5030Belgium Mudanjiang Branch of Heilongjiang Academy of Agricultural Sciences Mudanjiang 157000P.R.China

The wheat aphid, Sitobion miscanthi, is one of the most destructive pests of wheat plants in the temperate regions of China. Little is known about the genetic structure evolution of the different geographic populations of S. miscanthi with its migration. In this study, we investigated the population genetic structure and demographic history of S. miscanthi by analysing 18 geographical populations across China using one mitochondrial gene, COI;one nuclear gene, EF-1α;and two endosymbiont Buchnera genes, gnd and trpA. Analysis of data from the various groups showed high haplotype diversity and low nucleotide variation. SAMOVA analysis did not find a correlation between genetic distance and geographic distance. However, areas with high population diversity exhibited high haplotype diversity. Therefore, we speculate that there are two main natural migration pathways of S. miscanthi in China. One is from Yunnan to the Sichuan Basin, and the other is from Wuhan, Xinyang and Jiaodong Peninsula areas to the northwest. Based on this hypothesis, we inferred that these aphid populations appear first in the southwestern and southern regions and spread to the north with the help of the southeastern and southwestern monsoons, which occur in spring and summer. In autumn, the aphids spread southward with the northeastern and northwestern monsoons.

关键词： Sitobion miscanthi molecular marker COI symbiotic bacteria phylogenetic tree

Comparison of 2-acetylfuran,2-ethylfuran,and 2-methylfuran spherically expanding flame intrinsic instabilities

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Science China(Technological Sciences) 2022年第10期65卷 2388-2398页

作者： XU CangSu WANG QianWen LI XiaoLu OPPONG francis LIU WeiNan College of Energy Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China College of Mechanical and Electrical Engineering Key Laboratory of Intelligent Manufacturing Quality Big Data Tracing and Analysis of Zhejiang ProvinceChina Jiliang UniversityHangzhou 310018China

The intrinsic instability of three furan derivatives, namely, 2-acetylfuran(AF), 2-ethylfuran(EF), and 2-methylfuran(MF), is experimentally and theoretically investigated and compared. A deep-learning-based end-to-end system is used to segment the cells and measure the crack length on the cellular flame front of the spherically expanding flame to quantitively investigate the flame morphology. Moreover, the flame front radius profile is quantitively investigated to shed light on the correlation between disturbance amplitude and flame radius. With the use of the linear stability model, the theoretical critical flame radius and Peclet number are obtained and compared to their corresponding experimental results to characterize the outset of cellularization and evaluate the flame instability propensity. Our analysis shows that compared with AF and EF, MF is prone to cellularization at a smaller flame radius and has a faster cell proliferation rate and crack length growth rate before reaching the hydrodynamic saturation limit. Meanwhile, the average area of saturated cells tends to be similar for the three furan derivatives. Furthermore,AF premixed flame does not exhibit cellularization before the flame radius is less than 45 mm in low initial pressure.

关键词： furan derivatives spherical expanding flame flame intrinsic instability linear stability theory

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