55 research outputs found
Oriki Ogun (Praise of the God of Iron) by Mayowa Adeyemo
No full textLagos State University music student, Mayowa Adeyemo, praises Ogun (Yoruba Orisha/God of Iron). Recorded on July 26, 2013 at Peter King College of Music near Badagry, Lagos State. Keywords: African History; African Languages and Societies; Critical and Cultural Studies; Dance; Digital Humanities; Ethnic Studies; Ethnomusicology; Folklore; Gender, Race, Sexuality, and Ethnicity in Communication; Linguistic Anthropology; Oral History; Performance Studies; Poetry; Race and Ethnicity; Social and Cultural Anthropology; Sociology of Culture
An evangelical voice in Africa: the worldview background of the theology of Tokunboh Adeyemo (1 October 1944-17 March 2010)
No full textAfrica was blessed with a son of the calibre of Dr Tokunboh Adeyemo. Since he only recently passed away, we do not yet have (as far as the author is aware) an assessment of the legacy of this eminent Christian leader. This article is the first preliminary evaluation written from a reformational worldview perspective.
The set-up of the investigation is as follows: Firstly, a brief out- line is given of his life history, especially his training in the Evangelical tradition. Then, the décor (the overall situation of African Christianity) that was the background against which he lived and worked is painted. Thirdly, it is followed by the strengths and weaknesses of Evangelical Christianity of which Adeyemo was a representative. Fourthly, it is indicated how Adeyemo thought in line with post-Lausanne Evangelicalism. In the fifth place a preliminary worldview evaluation of his legacy is given. To assist possible future research a bibliography of his most important publications concludes the investigation
Time Index: Oriki Ogun (Praise of the God of Iron) by Mayowa Adeyemo
No full textThis file is the time index for " Oriki Ogun (Praise of the God of Iron) by Mayowa Adeyemo
Design and analysis of memristor-based reliable crossbar architectures
No full textThe conventional transistor-based computing landscape is already undergoing dramatic
changes. While transistor-based devices’ scaling is approaching its physical limits in
nanometer technologies, memristive technologies hold the potential to scale to much
smaller geometries.
Memristive devices are used majorly in memory design but they also have unignorable
applications in logic design, neuromorphic computing, sensors among many others. The
most critical research and development problems that must be resolved before memristive
architectures become mainstream are related to their reliability. One of such reliability
issue is the sneak-paths current which limits the maximum crossbar array size. This thesis
presents various designs of the memristor based crossbar architecture and corresponding
experimental analysis towards addressing its reliability issues.
Novel contribution of this thesis starts with the formulation of robust analytic models
for read and write schemes used in memristive crossbar arrays. These novel models are
less restrictive and are suitable for accurate mathematical analysis of any mn crossbar
array and the evaluation of their performance during these critical operations. In order
to minimise the sneak-paths problem, we propose techniques and conditions for reliable
read operations using simultaneous access of multiple bits in the crossbar array. Two
new write techniques are also presented, one to minimise failure during single cell write
and the other designed for multiple cells write operation. Experimental results prove that
the single write technique minimises write voltage drop degradation compared to existing
techniques. Test results from the multiple cells write technique show it consumes less
power than other techniques depending on the chosen configuration.
Lastly, a novel Verilog-A memristor model for simulation and analysis of memristor’s
application in gas sensing is presented. This proposed model captures the gas sensing
properties of titanium-dioxide using gas concentration to control the overall memristance
of the device. This model is used to design and simulate a first-of-its-kind sneak-paths
free memristor-based gas detection arrays. Experimental results from a 88 memristor
sensor array show that there is a ten fold improvement in the accuracy of the sensor’s
response when compared with a single memristor sensor
MEMRISTOR BASED SENSOR
No full textA sensor comprises a plurality of sensor elements arranged in an array . Each sensor element is memristive and has an
electrical resistance characteristic related to exposure to a species to be sensed . The sensor elements are arranged to be
connectable such that at least one sensor element is connected in parallel with at least one other sensor element . By using appropriate connections , the array of sensor elements
can be read
Reliable gas sensing with memristive array
No full textGas sensing is one of the proposed application field of memristive devices. We used a crossbar array of memristors as gas sensor using the HP labs fabricated TiO2 based memristor model in an attempt to improve sensing accuracy. We introduced the possibility of reliable multiple gases detection using multiple rows of memristors as separate sensor in a crossbar array. Our experimental results show that an array of memristors can minimise measurement errors as well as provide a good redundancy measure during gas sensing. Measurements taken from the sensors are also not affected by alternate current paths problem often experienced in crossbar architecture
Efficient sensing approaches for high-density memristor sensor array
No full textRecent research shows ever growing interest in the potential applications of memristive devices. Among the many proposed fields, sensing is one of the most interesting as it could lead to unprecedented sensor density and ubiquity in electronic systems. In this paper, a framework for efficient gas detection using memristor crossbar array is proposed and analysed. A novel Verilog-A based memristor model that emulates the gas sensing behaviour of doped metal oxides is developed for simulation and integration with design automation tools. Using this model, we propose and analyse three different gas detection structures based on array of memristor-based sensors. Gas presence together with some of its properties can be detected using resistance changes and spatial information from one or group of memristive sensors. Our simulation results show that depending on the organisation of the memristive elements and the sensing method, the response of the sensor varies providing a broader design space for future designers. For instance, with a 8 × 8 memristor sensor array, there is a ten times improvement in the accuracy of the sensor’s response when compared with a single memristor sensor but at the expense of extra area overhead
Determination of Reserve Estimate of Quartzite Deposit using Geoelectric Sounding and Laboratory Measurement - A Case Study of Ipinsa area, near Akure, Southwestern Nigeria
No full textA total of 36 Vertical Electrical Sounding data and laboratory analysis was carried out at southern part of Ipinsa, near Akure, Southwestern Nigeria with the aim of determining the reserve estimate of a portion of the quartzite deposit in the area. The Vertical Electrical Sounding (VES) method adopted Schlumberger configuration with half current electrode spacing varying from minimum of 1 to maximum of 40 to 150 m. The VES results delineated three to six geoelectric layers which correspond to the top soil, weathered layer, weathered basement, fractured basement and the presumed fresh basement. At the top soil, the resistivity varies from 38 to 878 ohm-m, while the thickness value ranges from 0.1 to 6.8 m. At the weathered layer, resistivity varies from 17 to 9749 ohm-m, while the thickness value ranges from 0.1 m to infinity. The weathered basement resistivity ranges from 24 to 18088 ohm-m, while the thickness values range from 0.6 m to infinity. The partially fractured basement resistivity varies from 62 to 1331ohm-m and its thickness range from 4.0 to 5.1 m. The quartzite layer resistivity value in the study area is generally greater than 150 ohm-m, with average thickness of 8.86 m. From the 14 quartzite samples collected across the study area, the average density value was determined to be 2.51 g/cm3 (2510 kg/m2). The area extent of the quartzite deposit was calculated to be 1,024,729 m2, while the volume of the quartzite deposit is 9,079,098 m3. The mass of the quartzite deposit was estimated to be 22,788,538 tonnes. Keywords: Vertical electrical sounding, laboratory measurement, density, thickness, area, volume and tonnage
Minimising impact of wire resistance in low-power crossbar array write scheme
No full textThis paper presents a circuit level analysis of write operation in memristor crossbar memory array with and without line resistance. Three write schemes: floating line, V/2 and V/3 are investigated. Analysis shows that floating line scheme could also be considered reliable in arrays with aspect ratio of 1:1 and negligible line resistance just like the latter two schemes. Further analysis also shows that high density crossbar structures cannot be designed using any of the three schemes with worst case line resistance and data distribution within the array. To solve this problem, we propose a voltage compensating technique for write voltage degradation caused by line resistance during write operation on crossbar array. This technique is able to enhance write voltage in the presence of worst case line resistance and thus enable the design of higher density and reliable crossbar array
The influence of age and sex on genetic associations with adult body size and shape: a large-scale genome-wide interaction study
No full textCorrected by Erratum: Correction: The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape: A Large-Scale Genome-Wide Interaction Study, in PLoS Genetics,12(6):e1006166. The arcOGEN Consortium should be listed as an author of this article.Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially between men and women. To systematically screen for age- and/or sex-specific effects of genetic variants on BMI and WHRadjBMI, we performed meta-analyses of 114 studies (up to 320,485 individuals of European descent) with genome-wide chip and/or Metabochip data by the Genetic Investigation of Anthropometric Traits (GIANT) Consortium. Each study tested the association of up to ~2.8M SNPs with BMI and WHRadjBMI in four strata (men ≤50y, men >50y, women ≤50y, women >50y) and summary statistics were combined in stratum-specific meta-analyses. We then screened for variants that showed age-specific effects (G x AGE), sex-specific effects (G x SEX) or age-specific effects that differed between men and women (G x AGE x SEX). For BMI, we identified 15 loci (11 previously established for main effects, four novel) that showed significant (FDR<5%) age-specific effects, of which 11 had larger effects in younger (<50y) than in older adults (≥50y). No sex-dependent effects were identified for BMI. For WHRadjBMI, we identified 44 loci (27 previously established for main effects, 17 novel) with sex-specific effects, of which 28 showed larger effects in women than in men, five showed larger effects in men than in women, and 11 showed opposite effects between sexes. No age-dependent effects were identified for WHRadjBMI. This is the first genome-wide interaction meta-analysis to report convincing evidence of age-dependent genetic effects on BMI. In addition, we confirm the sex-specificity of genetic effects on WHRadjBMI. These results may provide further insights into the biology that underlies weight change with age or the sexually dimorphism of body shape.Thomas W. Winkler ... Lyle J Palmer ... CHARGE Consortium, DIAGRAM Consortium, GLGC Consortium, Global-BPGen Consortium, ICBP Consortium, MAGIC Consortium ... et al
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