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  • Publication . Other literature type . Conference object . 2019
    Open Access English
    Authors: 
    Shivani Rajendra Teli; Stanislav Zvanovec; Zabih Ghassemlooy;
    Publisher: HAL CCSD
    Countries: United Kingdom, France
    Project: EC | VisIoN (764461)

    International audience; In this paper, we study the effect of smartphone camera exposure on the performance of optical camera communications (OCC) link. The exposure parameters of image sensor sensitivity (ISO), aperture and shutter speed are included. A static OCC link with a 8 × 8 red, green and blue (RGB) LED array employed as the transmitter and a smartphone camera as the receiver is demonstrated to verify the study. Signal-to-noise ratio (SNR) analysis at different ISO values, the effect of aperture and shutter speed on communication link quality is performed. While SNRs of 20.6 dB and 16.9 dB are measured at 1 m and 2 m transmission distance, respectively for a ISO value of 100, they are decreased to 17.4 dB and 13.32 dB for a ISO of 800. The bit error rate (BER) of a 1 m long OCC link with a camera's shutter speed of 1/6000 s is 1.3 × 10 −3 (i.e., below the forward error correction BER limit of 3.8 × 10 −3) and is dropped to 0.0125 at a shutter speed of 1/20 s. This study provides insight of the basic smartphone settings and the exposure adjustment for further complex OCC links.

  • Publication . Part of book or chapter of book . 2018
    Open Access English
    Authors: 
    Ammara Gul; Stephen D. Wolthusen;
    Publisher: HAL CCSD
    Country: France

    Part 2: Infrastructure Protection; International audience; State estimation is vital to the stability of control systems, especially in power systems, which rely heavily on measurement devices installed throughout wide-area power networks. Several researchers have analyzed the problems arising from bad data injection and topology errors, and have proposed protection and mitigation schemes. This chapter employs hierarchical state estimation based on the common weighted-least-squares formulation to study the propagation of faults in intermediate and top-level state estimates as a result of measurement reordering attacks on a single region in the bottom level. Although power grids are equipped with modern defense mechanisms such as those recommended by the ISO/IEC 62351 standard, reordering attacks are still possible. This chapter concentrates on how an inexpensive data swapping attack in one region in the lower level can influence the accuracy of other regions in the same level and upper levels, and force the system towards undesirable states. The results are validated using the IEEE 118-bus test case.

  • Publication . Part of book or chapter of book . 2019
    Closed Access
    Authors: 
    Dan E. Webster; Sandrine Roulland; James D. Phelan;
    Country: France
    Project: EC | LYMPHOSIGN (661066)

    Genome-wide screens are a powerful technique to dissect the complex network of genes regulating diverse cellular phenotypes. The recent adaptation of the CRISPR-Cas9 system for genome engineering has revolutionized functional genomic screening. Here, we present protocols used to introduce Cas9 into human lymphoma cell lines, produce high-titer lentivirus of a genome-wide sgRNA library, transduce and culture cells during the screen, isolate genomic DNA, and prepare a custom library for next-generation sequencing. These protocols were tailored for loss-of-function CRISPR screens in human lymphoma cell lines but are highly amenable for other experimental purposes.

  • Open Access English
    Authors: 
    Gregory R. Brady; Peter Petrone; Iva Laginja; Keira Brooks; Manxuan Zhang; Mamadou N'Diaye; Christopher Moriarty; John G. Hagopian; Rémi Soummer;
    Publisher: Society of Photo-Optical Instrumentation Engineers (SPIE)
    Countries: France, United States

    We discuss the use of parametric phase-diverse phase retrieval to characterize and optimize the transmitted wavefront of a high-contrast apodized pupil coronagraph with and without an apodizer. We apply our method to correct the transmitted wavefront of the HiCAT (High contrast imager for Complex Aperture Telescopes) coronagraphic testbed. This correction requires a series of calibration steps, which we describe. The correction improves the system wavefront from 16 nm RMS to 3.0 nm RMS for the case where a uniform circular aperture is in place. We further measure the wavefront with the apodizer in place to be 11.7 nm RMS. Improvement to the apodized pupil phase retrieval process is necessary before a correction based on this measurement can be applied.

  • Publication . Part of book or chapter of book . 2018
    Closed Access English
    Authors: 
    Thierry Billard; François Liger; Mathieu Verdurand;
    Publisher: HAL CCSD
    Country: France

    Abstract The serotonergic system plays a key modulatory role in the brain. This system is critical in many drug developments for brain disorders via interactions with the 14 subtypes of 5-HT receptors or through reuptake blockade. Positron emission tomography (PET) is an efficient tool for in vivo studies of physiological and pathological processes. Because of its pertinent radiochemical properties, fluorine-18 is one of the most used radioisotopes in PET imaging. This chapter will propose an overview of the 18F-radioligands targeting serotonin receptors, which have been developed over the last few years. Both radiosyntheses and pharmacological properties of these radiotracers will be described, with a specific emphasis on their potential medical applications.

  • Publication . Article . Part of book or chapter of book . 2020
    Open Access English
    Authors: 
    Hassen Nigatu; Yimesker Yihun;
    Publisher: HAL CCSD
    Country: France

    International audience; This study presents an algebraic method to detect, count, and identify concomitant motions of parallel robots at the velocity level. The pose and orientation of moving platform of parallel manipulators (PMs) with f-DOF could be commonly described by f possible motion variables on the instantaneous motion space (IMS) and (6 − f) restriction motion variables on the instantaneous restriction space (IRS). However, in some situations, PMs moving platform may accompanied by a concomitant (parasitic) motions along the direction of restriction space. Therefore, the commonly understood one-to-one correspondence between joint space and task space mobility of non-redundant PMs would be compromised. This phenomenon occurred due to the fact that the alignment of screws can change the reciprocal screws while the given screw systems are still maintained. To demonstrate the proposed method, an amplitude-based concomitant motion comparison is performed on two widely utilized lower-mobility parallel mechanisms, 3RPS and 3PRS. The result has shown that for the selected mechanisms, concomitant motion is identical regardless of their difference in joint arrangements in each limbs.

  • Publication . Conference object . Preprint . Part of book or chapter of book . Article . 2020
    Open Access English
    Authors: 
    Fabrice Boudot; Pierrick Gaudry; Aurore Guillevic; Nadia Heninger; Emmanuel Thomé; Paul Zimmermann;
    Publisher: HAL CCSD
    Country: France

    International audience; We report on two new records: the factorization of RSA-240, a 795-bit number, and a discrete logarithm computation over a 795-bit prime field. Previous records were the factorization of RSA-768 in 2009 and a 768-bit discrete logarithm computation in 2016. Our two computations at the 795-bit level were done using the same hardware and software, and show that computing a discrete logarithm is not much harder than a factorization of the same size. Moreover, thanks to algorithmic variants and well-chosen parameters, our computations were significantly less expensive than anticipated based on previous records.The last page of this paper also reports on the factorization of RSA-250.

  • Open Access English
    Authors: 
    Martin, Adrian; Coolsaet, Brendan; Corbera, Esteve; Dawson, Neil; Fisher, Janet; Franks, Phil; Mertz, Ole; Pascual, Unai; Rasmussen, Laura,; Ryan, Casey;
    Publisher: Routledge
    Countries: France, United Kingdom

    Land use intensification is widely considered to be an essential strategy for achieving global goals to eliminate poverty and to avoid damaging losses of ecosystem services. This chapter investigates whether current land use intensification activities are achieving these twin goals. To do so, it reviews a body of academic literature that reports on case studies in which both social and ecological outcomes of intensification are reported. There are two main findings. First, there are relatively few cases in which land use intensification is clearly succeeding in these twinned objectives. There are many more cases in which, for example, short-term income or productivity gains from land use intensification are resulting in long-term diminution of biodiversity and ecosystem services. Studies with longer-term perspectives are already seeing how such trade-offs are leading to negative feedbacks for human wellbeing, especially for marginalised social groups. Secondly, we learn most from those studies that a) go beyond measuring production and income to measure multiple dimensions of wellbeing and ecosystem services, b) monitor dynamics of outcomes across longer time periods and across landscapes and c) disaggregate outcome measures to identify outcomes for different social groups.

  • Publication . Part of book or chapter of book . 2020
    Open Access English
    Authors: 
    Robert H. Logie; Clément Belletier; Jason M Doherty;
    Publisher: HAL CCSD
    Countries: United Kingdom, France

    Multiple theories of working memory are described in the chapters of this book and often these theories are viewed as being mutually incompatible, yet each is associated with a supporting body of empirical evidence. This chapter argues that many of these differences reflect different research questions, different levels of explanation, and differences in how participants perform their assigned tasks in different laboratories, rather than fundamental theoretical adversity. It describes a version of a multiple component working memory in which a range of specialized cognitive functions (or mental tools) act in concert, giving the impression, at a different level of explanation, of a unified cognitive system. The chapter argues that more rapid and more substantial scientific progress on the understanding of the concept of working memory would be achieved through identifying the levels of explanation explored within each theoretical framework, and attempting to integrate theoretical frameworks rather than perpetuating debate with no clear resolution in sight.

  • Publication . Part of book or chapter of book . 2018
    Closed Access English
    Authors: 
    Heber Gamboa-Meléndez; Macarena Larroude; Young-Kyoung Park; Pauline Trebul; Jean-Marc Nicaud; Rodrigo Ledesma-Amaro;
    Publisher: HAL CCSD
    Country: France
    Project: EC | AGREENSKILLS (267196)

    International audience; Synthetic biology is an emergent field of research whose aim is to make biology an engineering discipline, thus permitting to design, control, and standardize biological processes. Synthetic biology is therefore expected to boost the development of biotechnological processes such as protein production and enzyme engineering, which can be significantly relevant for lipases and esterases.

search
Include:
2,039 Research products, page 1 of 204
  • Publication . Other literature type . Conference object . 2019
    Open Access English
    Authors: 
    Shivani Rajendra Teli; Stanislav Zvanovec; Zabih Ghassemlooy;
    Publisher: HAL CCSD
    Countries: United Kingdom, France
    Project: EC | VisIoN (764461)

    International audience; In this paper, we study the effect of smartphone camera exposure on the performance of optical camera communications (OCC) link. The exposure parameters of image sensor sensitivity (ISO), aperture and shutter speed are included. A static OCC link with a 8 × 8 red, green and blue (RGB) LED array employed as the transmitter and a smartphone camera as the receiver is demonstrated to verify the study. Signal-to-noise ratio (SNR) analysis at different ISO values, the effect of aperture and shutter speed on communication link quality is performed. While SNRs of 20.6 dB and 16.9 dB are measured at 1 m and 2 m transmission distance, respectively for a ISO value of 100, they are decreased to 17.4 dB and 13.32 dB for a ISO of 800. The bit error rate (BER) of a 1 m long OCC link with a camera's shutter speed of 1/6000 s is 1.3 × 10 −3 (i.e., below the forward error correction BER limit of 3.8 × 10 −3) and is dropped to 0.0125 at a shutter speed of 1/20 s. This study provides insight of the basic smartphone settings and the exposure adjustment for further complex OCC links.

  • Publication . Part of book or chapter of book . 2018
    Open Access English
    Authors: 
    Ammara Gul; Stephen D. Wolthusen;
    Publisher: HAL CCSD
    Country: France

    Part 2: Infrastructure Protection; International audience; State estimation is vital to the stability of control systems, especially in power systems, which rely heavily on measurement devices installed throughout wide-area power networks. Several researchers have analyzed the problems arising from bad data injection and topology errors, and have proposed protection and mitigation schemes. This chapter employs hierarchical state estimation based on the common weighted-least-squares formulation to study the propagation of faults in intermediate and top-level state estimates as a result of measurement reordering attacks on a single region in the bottom level. Although power grids are equipped with modern defense mechanisms such as those recommended by the ISO/IEC 62351 standard, reordering attacks are still possible. This chapter concentrates on how an inexpensive data swapping attack in one region in the lower level can influence the accuracy of other regions in the same level and upper levels, and force the system towards undesirable states. The results are validated using the IEEE 118-bus test case.

  • Publication . Part of book or chapter of book . 2019
    Closed Access
    Authors: 
    Dan E. Webster; Sandrine Roulland; James D. Phelan;
    Country: France
    Project: EC | LYMPHOSIGN (661066)

    Genome-wide screens are a powerful technique to dissect the complex network of genes regulating diverse cellular phenotypes. The recent adaptation of the CRISPR-Cas9 system for genome engineering has revolutionized functional genomic screening. Here, we present protocols used to introduce Cas9 into human lymphoma cell lines, produce high-titer lentivirus of a genome-wide sgRNA library, transduce and culture cells during the screen, isolate genomic DNA, and prepare a custom library for next-generation sequencing. These protocols were tailored for loss-of-function CRISPR screens in human lymphoma cell lines but are highly amenable for other experimental purposes.

  • Open Access English
    Authors: 
    Gregory R. Brady; Peter Petrone; Iva Laginja; Keira Brooks; Manxuan Zhang; Mamadou N'Diaye; Christopher Moriarty; John G. Hagopian; Rémi Soummer;
    Publisher: Society of Photo-Optical Instrumentation Engineers (SPIE)
    Countries: France, United States

    We discuss the use of parametric phase-diverse phase retrieval to characterize and optimize the transmitted wavefront of a high-contrast apodized pupil coronagraph with and without an apodizer. We apply our method to correct the transmitted wavefront of the HiCAT (High contrast imager for Complex Aperture Telescopes) coronagraphic testbed. This correction requires a series of calibration steps, which we describe. The correction improves the system wavefront from 16 nm RMS to 3.0 nm RMS for the case where a uniform circular aperture is in place. We further measure the wavefront with the apodizer in place to be 11.7 nm RMS. Improvement to the apodized pupil phase retrieval process is necessary before a correction based on this measurement can be applied.

  • Publication . Part of book or chapter of book . 2018
    Closed Access English
    Authors: 
    Thierry Billard; François Liger; Mathieu Verdurand;
    Publisher: HAL CCSD
    Country: France

    Abstract The serotonergic system plays a key modulatory role in the brain. This system is critical in many drug developments for brain disorders via interactions with the 14 subtypes of 5-HT receptors or through reuptake blockade. Positron emission tomography (PET) is an efficient tool for in vivo studies of physiological and pathological processes. Because of its pertinent radiochemical properties, fluorine-18 is one of the most used radioisotopes in PET imaging. This chapter will propose an overview of the 18F-radioligands targeting serotonin receptors, which have been developed over the last few years. Both radiosyntheses and pharmacological properties of these radiotracers will be described, with a specific emphasis on their potential medical applications.

  • Publication . Article . Part of book or chapter of book . 2020
    Open Access English
    Authors: 
    Hassen Nigatu; Yimesker Yihun;
    Publisher: HAL CCSD
    Country: France

    International audience; This study presents an algebraic method to detect, count, and identify concomitant motions of parallel robots at the velocity level. The pose and orientation of moving platform of parallel manipulators (PMs) with f-DOF could be commonly described by f possible motion variables on the instantaneous motion space (IMS) and (6 − f) restriction motion variables on the instantaneous restriction space (IRS). However, in some situations, PMs moving platform may accompanied by a concomitant (parasitic) motions along the direction of restriction space. Therefore, the commonly understood one-to-one correspondence between joint space and task space mobility of non-redundant PMs would be compromised. This phenomenon occurred due to the fact that the alignment of screws can change the reciprocal screws while the given screw systems are still maintained. To demonstrate the proposed method, an amplitude-based concomitant motion comparison is performed on two widely utilized lower-mobility parallel mechanisms, 3RPS and 3PRS. The result has shown that for the selected mechanisms, concomitant motion is identical regardless of their difference in joint arrangements in each limbs.

  • Publication . Conference object . Preprint . Part of book or chapter of book . Article . 2020
    Open Access English
    Authors: 
    Fabrice Boudot; Pierrick Gaudry; Aurore Guillevic; Nadia Heninger; Emmanuel Thomé; Paul Zimmermann;
    Publisher: HAL CCSD
    Country: France

    International audience; We report on two new records: the factorization of RSA-240, a 795-bit number, and a discrete logarithm computation over a 795-bit prime field. Previous records were the factorization of RSA-768 in 2009 and a 768-bit discrete logarithm computation in 2016. Our two computations at the 795-bit level were done using the same hardware and software, and show that computing a discrete logarithm is not much harder than a factorization of the same size. Moreover, thanks to algorithmic variants and well-chosen parameters, our computations were significantly less expensive than anticipated based on previous records.The last page of this paper also reports on the factorization of RSA-250.

  • Open Access English
    Authors: 
    Martin, Adrian; Coolsaet, Brendan; Corbera, Esteve; Dawson, Neil; Fisher, Janet; Franks, Phil; Mertz, Ole; Pascual, Unai; Rasmussen, Laura,; Ryan, Casey;
    Publisher: Routledge
    Countries: France, United Kingdom

    Land use intensification is widely considered to be an essential strategy for achieving global goals to eliminate poverty and to avoid damaging losses of ecosystem services. This chapter investigates whether current land use intensification activities are achieving these twin goals. To do so, it reviews a body of academic literature that reports on case studies in which both social and ecological outcomes of intensification are reported. There are two main findings. First, there are relatively few cases in which land use intensification is clearly succeeding in these twinned objectives. There are many more cases in which, for example, short-term income or productivity gains from land use intensification are resulting in long-term diminution of biodiversity and ecosystem services. Studies with longer-term perspectives are already seeing how such trade-offs are leading to negative feedbacks for human wellbeing, especially for marginalised social groups. Secondly, we learn most from those studies that a) go beyond measuring production and income to measure multiple dimensions of wellbeing and ecosystem services, b) monitor dynamics of outcomes across longer time periods and across landscapes and c) disaggregate outcome measures to identify outcomes for different social groups.

  • Publication . Part of book or chapter of book . 2020
    Open Access English
    Authors: 
    Robert H. Logie; Clément Belletier; Jason M Doherty;
    Publisher: HAL CCSD
    Countries: United Kingdom, France

    Multiple theories of working memory are described in the chapters of this book and often these theories are viewed as being mutually incompatible, yet each is associated with a supporting body of empirical evidence. This chapter argues that many of these differences reflect different research questions, different levels of explanation, and differences in how participants perform their assigned tasks in different laboratories, rather than fundamental theoretical adversity. It describes a version of a multiple component working memory in which a range of specialized cognitive functions (or mental tools) act in concert, giving the impression, at a different level of explanation, of a unified cognitive system. The chapter argues that more rapid and more substantial scientific progress on the understanding of the concept of working memory would be achieved through identifying the levels of explanation explored within each theoretical framework, and attempting to integrate theoretical frameworks rather than perpetuating debate with no clear resolution in sight.

  • Publication . Part of book or chapter of book . 2018
    Closed Access English
    Authors: 
    Heber Gamboa-Meléndez; Macarena Larroude; Young-Kyoung Park; Pauline Trebul; Jean-Marc Nicaud; Rodrigo Ledesma-Amaro;
    Publisher: HAL CCSD
    Country: France
    Project: EC | AGREENSKILLS (267196)

    International audience; Synthetic biology is an emergent field of research whose aim is to make biology an engineering discipline, thus permitting to design, control, and standardize biological processes. Synthetic biology is therefore expected to boost the development of biotechnological processes such as protein production and enzyme engineering, which can be significantly relevant for lipases and esterases.

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