4 research outputs found
Etude lexicale et aréale des désignations du pissenlit en domaine gallo-roman de France
International audienceSince 2015 we have participated in the ANR project "ECLATS ˗ Automated Extraction of Geolinguistic Atlas Content and Spatial Analysis: Application to Dialectology" (ANR-15-CE-380002). The aim of this project is to enhance the value of ancient linguistic atlases, such as The Linguistic Atlas of France (ALF), to facilitate the exploitation and dissemination of ALF maps, to define models combining linguistic and spatial dimensions to represent geo-linguistic data and finally to propose tools allowing the processing and geo-visualization of these data. As a part of this project, we have carried out the lexical and areal analysis of the dandelion designations in the Gallo-Romance area of France, ALF map n°1022. Here we present the results of our research and the tools used.Depuis 2015 nous participons au projet ANR « ECLATS ˗ Extraction automatisée des Contenus géoLinguistiques d'ATlas et analyse Spatiale : application à la Dialectologie » (ANR-15-CE-380002). Ce projet a pour objectifs de valoriser les atlas linguistiques anciens, tels que l'Atlas Linguistique de la France (ALF), de faciliter l'exploitation et la diffusion des cartes de l'ALF, de définir des modèles combinant les dimensions linguistiques, spatiales et temporelles pour représenter les données géo-linguistiques et enfin de proposer des outils permettant le traitement et la géo-visualisation de ces données. Dans le cadre de ce projet, nous avons effectué le traitement lexical et aréal des désignations du pissenlit à partir de la carte ALF n°1022. Nous proposons ici de présenter les résultats de nos recherches
Design and Performance Analysis of Generalized Hopping Codes for FH-CDMA Wireless Systems
跳頻分碼多工系統在無線通訊上的應用日益受到重視,在本論文中,我們提出一種藉著將最大相關性函數值提升到n,使得碼數目得以變多的新式質數碼,稱之為多階層質數碼。當P是一個質數而代表此質數之次方的n是一正整數,我們可得到碼之數目為P的n次方,這些碼之長度為P且最大相關函數值為n。在碼的長度不變,互相關函數性質變為n的情況下,可大幅提高碼的用戶量,並使其在頻寬不變的狀態下,大量增加同時使用系統之用戶的數目。此多階層質數碼可分為n的階層,如任意兩個碼在第l階層,則其相關函式值即為l。我們分析多階層質數碼在開關鍵移跳頻分碼多工系統中之效能。以往只能求得最大互相關函數值為2之碰撞機率,我們提供了最大互相關函數值為n中互相關函數值為n,n - 1,…,1。之碰撞機率可根據不同的需求,在系統效能與資料傳輸速率上選擇較佳的折衷解決辦法。我們的結果顯示在使用者數量與系統效能中,藉著階層的選擇取得有效的平衡。The application of frequency-hopping code-division multiple access (FH-CDMA) to wireless communication systems has been receiving significant attention recently. In this thesis, we study a new family of prime codes, so-called multi-level prime codes, with ex-panded code cardinality by relaxing the maximum cross-correlation function of λc to n, where n is a positive integer. If P is a prime number, our new constructions show that there are Pn sequence of length P and its maximum cross-correlation value is less than or equal to n. These multi-level prime codes can be partitioned into n levels, of which the cross-correlation peak between any two FH codes in level l is at most l ( where l ≤ n ). We analyze the performance of the multi-level prime codes in a conventional ON-OFF key-ing/FH-CDMA (OOK/FH-CDMA) system with hard-limiting detection, and provide the hit probability qn,0, qn,1, …, qn,n of having the cross-correlation values 0, 1, …, n, respectively. Our results show that there is a trade-off between code performance and cardinality.Chapter 1 Introduction 1
1.1 Background 1
1.2 FH-CDMA Systems 3
1.3 Various FH Codes 5
1.3.1 Prime Codes [17] 5
1.3.2 Quadratic Congruence Codes [6] 7
1.3.3 Cubic Codes [7] 10
1.4 Motivation and Outline of Thesis 13
Chapter 2 Construction of Multi-Level Prime Codes 15
2.1 Construction Algorithm 15
2.2 Correlation Property 17
Chapter 3 Performance Analysis of Multi-level Prime Codes 22
3.1 OOK/FH-CDMA Scheme 22
3.2 Effect of Multiple-Access Interference 27
3.3 Effect of Rayleigh Fading 29
3.4 Numerical Results 31
Chapter 4 Conclusions 34
Appendix A 35
Appendix B 36
References 3
Compromised SARS-CoV-2-specific placental antibody transfer
SARS-CoV-2 infection causes more severe disease in pregnant women compared to age-matched non-pregnant women. Whether maternal infection causes changes in the transfer of immunity to infants remains unclear. Maternal infections have previously been associated with compromised placental antibody transfer, but the mechanism underlying this compromised transfer is not established. Here, we used systems serology to characterize the Fc profile of influenza-, pertussis-, and SARS-CoV-2-specific antibodies transferred across the placenta. Influenza- and pertussis-specific antibodies were actively transferred. However, SARS-CoV-2-specific antibody transfer was significantly reduced compared to influenza- and pertussis-specific antibodies, and cord titers and functional activity were lower than in maternal plasma. This effect was only observed in third-trimester infection. SARS-CoV-2-specific transfer was linked to altered SARS-CoV-2-antibody glycosylation profiles and was partially rescued by infection-induced increases in IgG and increased FCGR3A placental expression. These results point to unexpected compensatory mechanisms to boost immunity in neonates, providing insights for maternal vaccine design.NIH (Grants 3R37AI080289-11S1, R01AI146785, U19AI42790-01, U19AI135995-02, U19AI42790-01, 1U01CA260476 – 01, CIVIC5N93019C00052)Bill and Melinda Gates Foundation (Awards OPP1146996 and INV- 001650