46 research outputs found

    Average Sound Absorption per Person at Octave Band Frequencies Between 125Hz And 4000Hz in an Enclosure

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    The audience constitutes the major sound absorbent materials in most church auditoria and, non-inclusion of the sound absorbed by the audience in the determination of the optimum reverberation time from the design stage accounts for the problem of poor sound quality in such church auditoria. To address this problem, this research was carried out to provide designers with data on sound absorption by an individual at some octave band frequencies important for understanding speech. The work utilized the Sabine’s formula for Reverberation Time to determine the sound absorption per person at Octave band frequencies of 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz and 4000Hz.  Data which included the volume, sitting capacity of persons and reverberation time of eight (8) churches were obtained when the churches were occupied and when unoccupied.  These data gave the calculated average sound absorption per person of 0.29, 0.43, 0.51, 0.68, 0.71 and 0.73 at these octave band frequencies respectively, all showing that the average sound absorption by an individual increases with frequency within this octave band frequency range. Key Words: Reverberation Time, Sound Absorption, Octave Band Frequency

    A Robust Color Image Watermarking Scheme Using Entropy and QR Decomposition

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    Internet has affected our everyday life drastically. Expansive volumes of information are exchanged over the Internet consistently which causes numerous security concerns. Issues like content identification, document and image security, audience measurement, ownership, copyrights and others can be settled by using digital watermarking. In this work, robust and imperceptible non-blind color image watermarking algorithm is proposed, which benefit from the fact that watermark can be hidden in different color channel which results into further robustness of the proposed technique to attacks. Given method uses some algorithms such as entropy, discrete wavelet transform, Chirp z-transform, orthogonal-triangular decomposition and Singular value decomposition in order to embed the watermark in a color image. Many experiments are performed using well-known signal processing attacks such as histogram equalization, adding noise and compression. Experimental results show that proposed scheme is imperceptible and robust against common signal processing attacks

    Déterminants socio-économiques de la production de lentille de terre [Macrotyloma geocarpum (Harms) Maréchal & Baudet] au Bénin

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    La lentille de terre (Macrotyloma geocarpum) est une lĂ©gumineuse populaire au BĂ©nin, dont le niveau de production est restĂ© stagnant, voire en lĂ©gĂšre baisse au cours de la derniĂšre dĂ©cennie. L’objectif de cette Ă©tude Ă©tait d’analyser les dĂ©terminants socio-Ă©conomiques et culturels de la production de M. geocarpum au BĂ©nin. Une enquĂȘte a Ă©tĂ© menĂ©e au moyen de discussions de groupe et d’entretiens individuels sur un Ă©chantillon de 103 producteurs de lentille de terre identifiĂ©s grĂące Ă  l’approche d’échantillonnage « boule de neige » Ă  travers 21 villages rĂ©partis dans cinq communes productrices du dĂ©partement du Zou. Il a Ă©tĂ© observĂ© que la production de la lentille de terre Ă©tait dĂ©terminĂ©e principalement par l’ñge, le sexe, la classe sociale, la distance de la maison au champ, le soutien de la vulgarisation, le groupe ethnique et la superficie emblavĂ©e pour la production. D’autre part, l’abandon de la production Ă©tait principalement dĂ» Ă  un accĂšs et un contrĂŽle limitĂ© des ressources par les femmes ; accĂšs limitĂ© Ă  l’éducation et non-implication des femmes dans les instances de prise de dĂ©cision ; les variations climatiques, la pĂ©nurie de main-d’Ɠuvre occasionnelle et le manque de soutien financier Ă  la production. &nbsp

    Robust non-blind color video watermarking using QR decomposition and entropy analysis

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    Issues such as content identification, document and image security, audience measurement, ownership and copyright among others can be settled by the use of digital watermarking. Many recent video watermarking methods show drops in visual quality of the sequences. The present work addresses the aforementioned issue by introducing a robust and imperceptible non-blind color video frame watermarking algorithm. The method divides frames into moving and non-moving parts. The non-moving part of each color channel is processed separately using a block-based watermarking scheme. Blocks with an entropy lower than the average entropy of all blocks are subject to a further process for embedding the watermark image. Finally a watermarked frame is generated by adding moving parts to it. Several signal processing attacks are applied to each watermarked frame in order to perform experiments and are compared with some recent algorithms. Experimental results show that the proposed scheme is imperceptible and robust against common signal processing attacks

    A more complete definition for promiscuous soybean

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    Open Access JournalAbstract Following a series of research on promiscuous nodulation, it came out that it is incomplete to define ‘promiscuous soybean’ as soybean cultivars with the sole ability to form nodules freely with indigenous Bradyrhizobium strains without requiring the specific type, Bradyrhizobium japonicum. This paper proposes a more complete definition which caters for both nodulation and biological nitrogen fixation ability. Keywords : Promiscuous soybean; Nodulation; Biological nitrogen fixation; Bradyrhizobiu

    Assessing Faculty’s Use of Social Network Tools in Libyan Higher Education via a Technology Acceptance Model

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    Recently, many educational institutes are expanding their education delivery methodologies to incorporate online, remote, and flexible learning, which is a strategic response to facilitate and fulfil the increasing demand for access to higher education. Unfortunately, online education requires substantial investments in different online education platforms, technologies, and infrastructure, creating obstacles for realising the online education strategy for many developing countries. In this paper, we argue that we could use social networks as one of the delivery platforms for online education, due to their easy access and popularity among young generations. Therefore, we carried out this study to measure and analyse the acceptance of faculty and educational stakeholders for social networks adoption as an educational delivery platform. Hence, we adapted the Technology Acceptance Model (TAM) to determine and analyse the factors and variants affecting faculty’s acceptance. We used the TAM as an internal variable, and we used privacy, infrastructure, institutional support and access devices as external variables to assess the faculty needs for adopting social networks into educational settings. The study examined 14 hypotheses corresponding to these factors using data collected from 382 respondents in six different universities within Libya, performing structural equation modelling, descriptive analysis, and confirmatory factor analysis. Results show that privacy, institutional support, perceived usefulness and perceived ease of use were seen to have a significant effect on behavioural intention. Additionally, perceived ease of use and behavioural intention contributed significantly towards the actual usage of social networks. The results also show that faculty and educational stakeholders have not provided enough for institutions or encouraged the use of social networks within the context of educational institutions across Libya.Publisher's Versio

    Mode of inheritance of promiscuous nodulation and combining abilities in soybean genotypes

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    Article purchasedKnowledge of the mode of inheritance of a trait can be a powerful decision-making tool in a breeding program, as it helps predicting selection gain, defining breeding strategy and choosing parental lines. This study aimed at estimating genetic parameters to infer the mode of inheritance of promiscuous nodulation in soybean. Half diallel crosses were made among nine parental lines. F2 progenies were field evaluated together with parents for nodulation characteristics and grain yield in response to Bradyrhizobium sp. strain USDA 3456. Data on nodule number (NN), percent of effective nodules (NE), fresh and dry weight of nodules (NFW and NDW), and grain yield were subjected to analysis of variance, and progenies’ means regression against parents’ was performed following Griffing’s Method2/Model 1. General and specific combining abilities, broad and narrow sense heritabilities, and Baker’s ratio were estimated. The study showed predominant GCA effect for all measured traits except NE. Broad and narrow sense heritabilities were high for grain yield and NDW, moderate for NN and NFW, and low for NE. Baker’s ratio was high for all measured traits except for NE. Overall, additive gene action was more important for all measured traits, except NE where non-additive gene action was more important. The high to moderate heritabilities for most traits showed that substantial gain can be achieved through selection

    Valorisation des EspÚces Négligées et Sous-Utilisées pour la Sécurité Alimentaire : Traits Morphologiques, Conservation et Regénération des Graines de Blighia sapida K.D. Koenig (Sapindaceae) Suivant les Phytodistricts du Bénin

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    Blighia sapida est une espĂšce trĂšs domestiquĂ©e au BĂ©nin et dont les fruits riches sur le plan nutritionnel sont utilisĂ©s pour des raisons alimentaire, phytothĂ©rapeute et cosmĂ©tique. MalgrĂ© son niveau de domestication, l’espĂšce se trouve aujourd’hui dans une situation de rĂ©gression progressive dans les agro-forĂȘts. Les causes majeures pourraient ĂȘtre la sĂ©lection de provenances moins performantes et l’usage des semences de mauvaises qualitĂ©s dues Ă  la viabilitĂ© trĂšs limitĂ©e dans le temps des graines de Blighia sapida si elles ne sont pas bien conservĂ©es. Face Ă  ce flĂ©au, au fil des gĂ©nĂ©rations, les communautĂ©s locales ont dĂ©veloppĂ© des connaissances endogĂšnes sur des techniques de conservation moins couteuses ayant rĂ©vĂ©lĂ© leurs utilitĂ©s dans le processus de rĂ©gĂ©nĂ©ration de l’espĂšce. Cette Ă©tude a portĂ© sur la caractĂ©risation des traits morphologiques des graines de Blighia sapida, ses pratiques de conservation et de dissĂ©mination suivants les rĂ©gions agro Ă©cologiques du BĂ©nin. Pour cela, il a Ă©tĂ© procĂ©dĂ© Ă  la sĂ©lection dans chaque phytodistrict, des arbres sur lesquels des fruits murs ont Ă©tĂ© rĂ©coltĂ©s puis mis en sachet Ă©tiquetĂ© et conservĂ© dans un sac glaciĂšre muni de gels rĂ©frigĂ©rants. Avec l’usage d’un pied Ă  coulisse et d’une balance Ă©lectronique de prĂ©cision, les paramĂštres morphomĂ©triques ont Ă©tĂ© collectĂ©s sur les graines extraites des fruits. Les rĂ©sultats obtenus ont montrĂ© qu’au BĂ©nin, sur le plan statistique, il n’y’a pas de variabilitĂ© significative des graines entre les provenances Ă©tudiĂ©es. Cependant, la provenance nord a obtenu les meilleurs rĂ©sultats sur le poids (59,36 g ± 14,68), l’épaisseur (16,136 mm ± 2,671) et la largeur (20,658 mm ± 2,965) des graines. Ces derniĂšres rĂ©coltĂ©es en saison sĂšche, peuvent ĂȘtre conservĂ©es au soleil, Ă  la tempĂ©rature ambiante ou au frais  pour une durĂ©e comprise entre 10 et 30 jours. D’aprĂšs les communautĂ©s locales, B. sapida se rĂ©gĂ©nĂšre naturellement (82,5%) ; nĂ©anmoins la multiplication par semis de graines (17,5%) se pratique le plus souvent au nord du pays. A la sortie de cette Ă©tude, il s’avĂšre indispensable d’élargir ces activitĂ©s Ă  toutes les zones agro-Ă©cologique du BĂ©nin afin de pouvoir affirmer ou infirmer ces informations et de pouvoir sĂ©lectionner une meilleure semence qui sera destinĂ©e aux programmes de dĂ©veloppement.   Blighia sapida is a highly domesticated species in Benin whose nutritionally rich fruits are used for food, herbal medicine and cosmetics. Despite its level of domestication, the species is now in a situation of gradual regression in agro-forests. The latter, the major causes of which could be the selection of less efficient provenances and the use of poor quality seeds due to the very limited viability over time of Blighia sapida seeds if they are not well preserved. Faced with this scourge, over generations, local communities have developed endogenous knowledge of less expensive conservation techniques that have revealed their usefulness in the regeneration process of the species. This study focused on the characterization of the morphological traits of Blighia sapida seeds, its conservation and dissemination practices following the agro-ecological regions of Benin. For this, trees were selected in each phytodistrict from which ripe fruits were harvested and then put in a labeled bag and kept in a cooler bag fitted with freezing gels. With the use of a caliper and a precision electronic scale, the morphometric parameters were collected on the seeds extracted from the fruits. The results obtained showed that in Benin, statistically, there is no significant variability of the seeds between the provenances studied. However, the northern provenance obtained the best results on the weight (59.36g±14.68), the thickness (16.136mm±2.671) and the width (20.658mm±2.965) of the seeds. The latter, harvested in the dry season, can be stored in the sun, at room temperature or sometimes buried under the ground for a period of between 10 and 30 days. According to local communities, B. sapida regenerates naturally (82.5%); nevertheless, propagation by seed sowing (17.5%) is most often practiced in the north of the country. At the end of this study, it is essential to extend these activities to all the agro-ecological zones of Benin in order to be able to affirm or refute this information and to be able to select a better seed which will be intended for development programs

    EspĂšces VĂ©gĂ©tales NĂ©gligĂ©es et Sous-UtilisĂ©es en Afrique de l’Ouest : Traits Morphologiques, Conservation et DissĂ©mination des Graines de Blighia sapida K.D. Koenig (Sapindaceae) Suivant les Zones Agro-Ă©cologiques du BĂ©nin

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    Blighia sapida est une espĂšce trĂšs domestiquĂ©e au BĂ©nin et dont les fruits riches sur le plan nutritionnel sont utilisĂ©s pour des raisons alimentaire, phytothĂ©rapeute et cosmĂ©tique. MalgrĂ© son niveau de domestication, l’espĂšce se trouve aujourd’hui dans une situation de rĂ©gression progressive dans les agro-forĂȘts. Cette derniĂšre, dont les causes majeures pourraient ĂȘtre la sĂ©lection de provenances moins performantes et l’usage des semences de mauvaises qualitĂ©s dues Ă  la viabilitĂ© trĂšs limitĂ©e dans le temps des graines de Blighia sapida si elles ne sont pas bien conservĂ©es. Face Ă  ce flĂ©au, au fil des gĂ©nĂ©rations, les communautĂ©s locales ont dĂ©veloppĂ© des connaissances endogĂšnes sur des techniques de conservation moins couteuses ayant rĂ©vĂ©lĂ© leurs utilitĂ©s dans le processus de rĂ©gĂ©nĂ©ration de l’espĂšce. Cette Ă©tude a portĂ© sur la caractĂ©risation des traits morphologiques des graines de Blighia sapida, ses pratiques de conservation et de dissĂ©mination suivants les rĂ©gions agro Ă©cologiques du BĂ©nin. Pour cela, il a Ă©tĂ© procĂ©dĂ© Ă  la sĂ©lection dans chaque phytodistrict, des arbres sur lesquels des fruits murs ont Ă©tĂ© rĂ©coltĂ©s puis mis en sachet Ă©tiquetĂ© et conservĂ© dans un sac glaciĂšre muni de gels rĂ©frigĂ©rants. Avec l’usage d’un pied Ă  coulisse et d’une balance Ă©lectronique de prĂ©cision, les paramĂštres morphomĂ©triques ont Ă©tĂ© collectĂ©s sur les graines extraites des fruits. Les rĂ©sultats obtenus ont montrĂ© qu’au BĂ©nin, sur le plan statistique, il n’y’a pas de variabilitĂ© significative des graines entre les provenances Ă©tudiĂ©es. Cependant, la provenance nord a obtenu les meilleurs rĂ©sultats sur le poids (59,36g±14,68), l’épaisseur (16,136mm±2,671) et la largeur (20,658mm±2,965) des graines. Ces derniĂšres rĂ©coltĂ©es en saison sĂšche, peuvent ĂȘtre conservĂ©es au soleil, Ă  la tempĂ©rature ambiante ou parfois enfouis sous le sol pour une durĂ©e comprise entre 10 et 30 jours. D’aprĂšs les communautĂ©s locales, B. sapida se rĂ©gĂ©nĂšre naturellement (82,5%) ; nĂ©anmoins la multiplication par semis de graines (17,5%) se pratique le plus souvent au nord du pays. A la sortie de cette Ă©tude, il s’avĂšre indispensable d’élargir ces activitĂ©s Ă  toutes les zones agro-Ă©cologique du BĂ©nin afin de pouvoir affirmer ou infirmer ces informations et de pouvoir sĂ©lectionner une meilleure semence qui sera destinĂ©e aux programmes de dĂ©veloppement.   Blighia sapida is a highly domesticated species in Benin whose nutritionally rich fruits are used for food, herbal medicine and cosmetics. Despite its level of domestication, the species is now in a situation of gradual regression in agro-forests. The latter, the major causes of which could be the selection of less efficient provenances and the use of poor quality seeds due to the very limited viability over time of Blighia sapida seeds if they are not well preserved. Faced with this scourge, over generations, local communities have developed endogenous knowledge of less expensive conservation techniques that have revealed their usefulness in the regeneration process of the species. This study focused on the characterization of the morphological traits of Blighia sapida seeds, its conservation and dissemination practices following the agro-ecological regions of Benin. For this, trees were selected in each phytodistrict from which ripe fruits were harvested and then put in a labeled bag and kept in a cooler bag fitted with freezing gels. With the use of a caliper and a precision electronic scale, the morphometric parameters were collected on the seeds extracted from the fruits. The results obtained showed that in Benin, statistically, there is no significant variability of the seeds between the provenances studied. However, the northern provenance obtained the best results on the weight (59.36g±14.68), the thickness (16.136mm±2.671) and the width (20.658mm±2.965) of the seeds. The latter, harvested in the dry season, can be stored in the sun, at room temperature or sometimes buried under the ground for a period of between 10 and 30 days. According to local communities, B. sapida regenerates naturally (82.5%); nevertheless, propagation by seed sowing (17.5%) is most often practiced in the north of the country. At the end of this study, it is essential to extend these activities to all the agro-ecological zones of Benin in order to be able to affirm or refute this information and to be able to select a better seed which will be intended for development programs

    EspĂšces VĂ©gĂ©tales NĂ©gligĂ©es et Sous-UtilisĂ©es en Afrique de l’Ouest : Traits Morphologiques, Conservation et DissĂ©mination des Graines de Blighia sapida K.D. Koenig (Sapindaceae) Suivant les Zones Agro-Ă©cologiques du BĂ©nin

    Get PDF
    Blighia sapida est une espĂšce trĂšs domestiquĂ©e au BĂ©nin et dont les fruits riches sur le plan nutritionnel sont utilisĂ©s pour des raisons alimentaire, phytothĂ©rapeute et cosmĂ©tique. MalgrĂ© son niveau de domestication, l’espĂšce se trouve aujourd’hui dans une situation de rĂ©gression progressive dans les agro-forĂȘts. Cette derniĂšre, dont les causes majeures pourraient ĂȘtre la sĂ©lection de provenances moins performantes et l’usage des semences de mauvaises qualitĂ©s dues Ă  la viabilitĂ© trĂšs limitĂ©e dans le temps des graines de Blighia sapida si elles ne sont pas bien conservĂ©es. Face Ă  ce flĂ©au, au fil des gĂ©nĂ©rations, les communautĂ©s locales ont dĂ©veloppĂ© des connaissances endogĂšnes sur des techniques de conservation moins couteuses ayant rĂ©vĂ©lĂ© leurs utilitĂ©s dans le processus de rĂ©gĂ©nĂ©ration de l’espĂšce. Cette Ă©tude a portĂ© sur la caractĂ©risation des traits morphologiques des graines de Blighia sapida, ses pratiques de conservation et de dissĂ©mination suivants les rĂ©gions agro Ă©cologiques du BĂ©nin. Pour cela, il a Ă©tĂ© procĂ©dĂ© Ă  la sĂ©lection dans chaque phytodistrict, des arbres sur lesquels des fruits murs ont Ă©tĂ© rĂ©coltĂ©s puis mis en sachet Ă©tiquetĂ© et conservĂ© dans un sac glaciĂšre muni de gels rĂ©frigĂ©rants. Avec l’usage d’un pied Ă  coulisse et d’une balance Ă©lectronique de prĂ©cision, les paramĂštres morphomĂ©triques ont Ă©tĂ© collectĂ©s sur les graines extraites des fruits. Les rĂ©sultats obtenus ont montrĂ© qu’au BĂ©nin, sur le plan statistique, il n’y’a pas de variabilitĂ© significative des graines entre les provenances Ă©tudiĂ©es. Cependant, la provenance nord a obtenu les meilleurs rĂ©sultats sur le poids (59,36g±14,68), l’épaisseur (16,136mm±2,671) et la largeur (20,658mm±2,965) des graines. Ces derniĂšres rĂ©coltĂ©es en saison sĂšche, peuvent ĂȘtre conservĂ©es au soleil, Ă  la tempĂ©rature ambiante ou parfois enfouis sous le sol pour une durĂ©e comprise entre 10 et 30 jours. D’aprĂšs les communautĂ©s locales, B. sapida se rĂ©gĂ©nĂšre naturellement (82,5%) ; nĂ©anmoins la multiplication par semis de graines (17,5%) se pratique le plus souvent au nord du pays. A la sortie de cette Ă©tude, il s’avĂšre indispensable d’élargir ces activitĂ©s Ă  toutes les zones agro-Ă©cologique du BĂ©nin afin de pouvoir affirmer ou infirmer ces informations et de pouvoir sĂ©lectionner une meilleure semence qui sera destinĂ©e aux programmes de dĂ©veloppement.   Blighia sapida is a highly domesticated species in Benin whose nutritionally rich fruits are used for food, herbal medicine and cosmetics. Despite its level of domestication, the species is now in a situation of gradual regression in agro-forests. The latter, the major causes of which could be the selection of less efficient provenances and the use of poor quality seeds due to the very limited viability over time of Blighia sapida seeds if they are not well preserved. Faced with this scourge, over generations, local communities have developed endogenous knowledge of less expensive conservation techniques that have revealed their usefulness in the regeneration process of the species. This study focused on the characterization of the morphological traits of Blighia sapida seeds, its conservation and dissemination practices following the agro-ecological regions of Benin. For this, trees were selected in each phytodistrict from which ripe fruits were harvested and then put in a labeled bag and kept in a cooler bag fitted with freezing gels. With the use of a caliper and a precision electronic scale, the morphometric parameters were collected on the seeds extracted from the fruits. The results obtained showed that in Benin, statistically, there is no significant variability of the seeds between the provenances studied. However, the northern provenance obtained the best results on the weight (59.36g±14.68), the thickness (16.136mm±2.671) and the width (20.658mm±2.965) of the seeds. The latter, harvested in the dry season, can be stored in the sun, at room temperature or sometimes buried under the ground for a period of between 10 and 30 days. According to local communities, B. sapida regenerates naturally (82.5%); nevertheless, propagation by seed sowing (17.5%) is most often practiced in the north of the country. At the end of this study, it is essential to extend these activities to all the agro-ecological zones of Benin in order to be able to affirm or refute this information and to be able to select a better seed which will be intended for development programs
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