Physico-mechanical Characteristics of High Density Briquettes produced from Composite Sawdust

Physico-mechanical characteristics of briquettes produced from composite sawdust admixture using a screw press briquetting machine was investigated. Sample feedstock materials collected has particle sizes varying between 6-8mm with 10-20% powdery components (< 4 mesh). Briquette’s physical characteristics investigated using standard test apparatus and procedures include dimensional stability immediately, 1 hour and 30 days after production, effects of particle moisture and particle size on briquette compressed and relaxed densities. Mechanical characteristics include resistance to gravity and impact, effects of densities on impact resistance index (IRI) and effects of briquette durability in water. Statistical models were used to establish empirical relationships between the feedstock materials (independent variables) and briquette characteristics (independent variables). The physical characteristics of briquettes produced at 12% are loose and brittle with poor dimensional stability, at 10% they are bonded but weak in strength with good dimensional stability while briquettes produced at 8% are wellformed, good colouration with char carbonation, excellent dimensional stability. The compressed density of the briquettes ranges of 490-820 kg/m3. The lower moisture briquettes have high resistance to water dispersion, high impact resistance and excellent storability. Keywords: Characterization, extrusion, briquette, sawmill, sawdus

Machine learning methods for sign language recognition: a critical review and analysis.

Sign language is an essential tool to bridge the communication gap between normal and hearing-impaired people. However, the diversity of over 7000 present-day sign languages with variability in motion position, hand shape, and position of body parts making automatic sign language recognition (ASLR) a complex system. In order to overcome such complexity, researchers are investigating better ways of developing ASLR systems to seek intelligent solutions and have demonstrated remarkable success. This paper aims to analyse the research published on intelligent systems in sign language recognition over the past two decades. A total of 649 publications related to decision support and intelligent systems on sign language recognition (SLR) are extracted from the Scopus database and analysed. The extracted publications are analysed using bibliometric VOSViewer software to (1) obtain the publications temporal and regional distributions, (2) create the cooperation networks between affiliations and authors and identify productive institutions in this context. Moreover, reviews of techniques for vision-based sign language recognition are presented. Various features extraction and classification techniques used in SLR to achieve good results are discussed. The literature review presented in this paper shows the importance of incorporating intelligent solutions into the sign language recognition systems and reveals that perfect intelligent systems for sign language recognition are still an open problem. Overall, it is expected that this study will facilitate knowledge accumulation and creation of intelligent-based SLR and provide readers, researchers, and practitioners a roadmap to guide future direction

Work Facets Predicting Overall Job Satisfaction among Teachers in Selected Secondary schools in Ibadan South-West Nigeria: A Minnesota Satisfaction Questionnaire Survey

Background: Global measures are often used to assess employees’ job satisfaction. However, important information is lost when this approach is  adopted. The use of multidimensional approach provides robust information for potential intervention. This study aimed to assess the work facets  predicting the overall single-item job satisfaction measure among teachers in Ibadan, Nigeria. Methods: This was a cross-sectional descriptive study conducted among 476 secondary school teachers selected using a multistage sampling  method. A structured questionnaire was used for data collection while data was analyzed using SPSS version 26. The Minnesota Satisfaction  Questionnaire (MSQ) and a single-item satisfaction measure assessed satisfaction. A linear regression model of the overall job satisfaction was developed. P-value ≤ 0.05 was regarded as statistically significant. Results: The mean age of respondents was 38.1±9.0 years. Majority of respondents were females 263 (55.3%) and married 363 (76.3%). The  respondents expressed above average satisfaction with all work facets except compensation 161 (33.8%) and work conditions 223 (46.8%). The work  facets which significantly predicted overall job satisfaction included: supervision-human relations (β = 0.121: 95% CI = 0.013 to 0.229; p = 0.028);policies & practices (β = 0.111: 95% CI = 0.021 to 0.201; p = 0.016); compensation (β =0.125: 95% CI = 0.035 to 0.214; p = 0.006) and recognition (β = 0.113: 95% CI = 0.006 to 0.220; p = 0.039) Conclusion: Overall job satisfaction was mostly predicted by factors extrinsic to the job, so these could be specifically targeted for interventions to  improve job satisfaction among teachers

Synthesis, Characterization and Kinetic Studies of Nickel (Ii) Complex of Dibenzoyl Methane and It’s Adduct

Nickel (II) Complex of dibenzoylmethane and the 1, 10 phenantroline adduct were synthesized using Nickel (II) acetate tetrahydrate in aqueous methanol. The resulting green Ni2+ compounds were characterized by elemental analysis, magnetic moments, IR and UV spectroscopy. The kinetics of the reaction for the formation of the complex   was conducted. The complex and adduct were identified by coupled vibrations of Ni-O + Ni-N which were conspicuously absent in the neat ligand .The elemental and metal analysis indicates 1:2 Metal-Ligand ratio in both complex and adduct. The electronic spectral and magnetic susceptibility studies are consistent with the adoption of an octahedral geometry for the adduct.  Results of the kinetic study showed that the formation of the nickel complex occurs at a rate of 1.7 x 103 – 9.2 x 103 moldm-3 in a 2nd order  reversible reaction, which involved both the metal and the ligand with equilibrium constant Keq ranging from 2.0 x 104 – 1.5 x 106. The observed rate is at variance with the rate of solvent exchange, this being typical of a tautomeric ligand. Keywords: 1, 10-phenantroline, Dibenzoylmethane, Kinetics, Solvent-exchange

Gut microflora of cultured and captured Clarias gariepinus

The diversity and microbial load of the micro flora inhabiting the gut sections of captured and the cultured Clarias gariepinus were investigated. The gut contents of the fish were isolated and characterized using standard method. The results of the characterization revealed the presence of bacteria and fungi in the guts of the fish. The bacteria isolated from the captured fish were Escherichia coli, Proteus vulgaris, Klebsiella mobilis, Enterobacter spp, Shigella spp, and Micrococcus varians while Citrobacter spp, Proteus vulgaris, Enterobacter spp, Escherichia coli, Serratia marcescens and Shigella spp were isolated from the cultured fish.. The fungi isolates found in the gut of the captured fish included, Penicillium chrysogenum, Fusarium spp and Rhizopus stolonifer while Aspergillus flavus, Candida albicans and Aspergillus fumigates were isolated in the cultured fish. The bacteria count obtained from the fore gut, mid gut and hind gut of the captured fish were; 1.4 x 1O-~B cfu/g, 1.7 x 1O-~B cfu/g and 2.7 x 1O-~B cfu/g while that of cultured fish had 2.8 x 10-~B cfu/g, 2.05 x 10-~Bcfu/g and 2.65 x 10-~Bcfu/g respectively. The spore count of the fungi isolated from the fore gut, mid gut and hind gut of captured fish ranged between 4.0 x 10-~B spore/g and 9.0 x 1O-~B spore/g while the count obtained from the cultured fish ranged between 3.0 x 10-~B and 9.05 x 1O-~B spore/g. The hind gut had the highest number of species and microbial load in both captured and cultured fish than the other region. Though, there was significant difference (P0.05). The results therefore suggest that there is diversity in microbial composition and microbial load in different sections of the gut of cultured and captured fish which may reflect of the environment where they were raised

Investigación previa del conjunto catedralicio de Granada

Antes de emprender la restauración o estudio de los procesos de alteración de un monumento, es imprescindible la realización de una serie de estudios preliminares conocidos genéricamente como investigación previa; estos estudios deben proporcionar suficiente información sobre muy diversos aspectos al objeto de poder estar en condiciones de realizar una adecuada interpretación de los datos que se obtengan en las investigaciones siguientes a fin de garantizar, en la medida de lo posible, que las futuras intervenciones sean las más adecuadas. Es necesario, en primer lugar, realizar una investigación profunda que permita conocer las diversas etapas constructivas del monumento, las modificaciones que se han realizado sobre el proyecto original, así como todas aquellas incidencias que puedan haber tenido una repercusión directa sobre el monumento,tales como derrumbamientos, terremotos, modificaciones urbanísticas del entorno, etc. En segundo lugar, se ha de realizar una investigación bibliográfica que permita conocer la procedencia de los materiales pétreos empleados en la construcción; esta información será esencial tanto para el investigador como para el arquitecto restaurador. Al primero le servirá para poder obtener grandes cantidades de material inalterado para la realización de ensayos de laboratorio, que no puede detraerse del monumento sin causar en la mayor parte de los casos graves daños; al restaurador, esta información le permitirá disponer de material de las mismas o similares características al original por si fuese necesario realizar reposiciones. La localización de las canteras de procedencia de los materiales es a veces una tarea no demasiado fácil por diversas razones, entre las que se encuentra el hecho de que muchas de ellas no se encuentran en explotación desde hace muchos años, o el nombre por el que son mencionadas en los antiguos documentos no se corresponde con el actual, etc., no obstante, diversos estudios químicos y petrográficos pueden permitir la identificación inequívoca de las mismas comparando con los materiales del edificio . Por último, el conocimiento de las condiciones ambientales a las que se encuentra sometido el monumento resulta de un particular interés debido a que muchos procesos de alteración tendrán su origen en las mismas y, además, las tareas de restauración a realizar se pueden ver fuertemente condicionadas por aquellas

Seismo-Structural Interpretation and Petrophysical Evaluation of Ugwu-Field, Coastal Swamp Depositional Belt of the Niger Delta Basin

Structural interpretation of 3-D seismic data and well log have been applied to unravel hydrocarbon entrapment pattern and petrophysical  parameters of X-field within the coastal swamp region of the Niger Delta.. Four reservoir intervals (A, B, C and D) delineated as (W-026, 032, 042 and 048) using gamma ray and resistivity log response. Structural interpretation for inline 5158 revealed four horizons (A, B, C and D) and eight (8) faults labelled (F1, F2, F12, F13, F21, F22, F23, and F24) were mapped. It was observed that the hanging wall block due to reverse drag or rollover anticline slided over fault F12 and created fault F2, thereby creating subsidence where sediments can be deposited. Therefore, faults F2 and F12 created rollover structures which cuts across the entire four reservoirs and invaluably responsible for trapping of hydrocarbon in the field. RMS map developed for horizons ‘A’ and ‘B’ revealed high amplitude anomalies, while variance attribute for both horizons showed relatively uniform lithology observed from east to west across the study area. While from north-east to south west, variance was observed to increase relatively which indicates different lithology. These trend exposes dipping of the channel fill at both flanks by creating extensive faulting. Results of petrophysical evaluation for reservoirs ‘A’ and ‘B’ across the four wells were analyzed. For reservoir ‘A’, porosity values of 32.8%, 24.8%, 25.9% and 27.1% were obtained for wells W-048, 042, 026 and 032 respectively with an average of 27.65%, while for reservoir ‘B’ porosity values of 26.83%, 26.93%, 25.59% and 27.99% for wells W-048, 042, 026 and 032 were obtained respectively with an average of 26.84%. This porosity values were rated very good to excellent for reservoir ‘A’ and very good for reservoir ‘B’, while Permeability values of the order (K > 1000mD) were obtained for both reservoirs across the four wells and is rated excellent. Hydrocarbon saturation (Shc) across the four wells averages at 68.57% for reservoir ‘A’ and 68.67% for reservoir ‘B’ which is high. Log motifs using gamma ray log for well-026 was integrated with seismic facies to infer on depositional environment of the reservoirs horizons showed a combination of serrated funnel/blocky shape log response and coarsening upward cycles. For reservoirs ‘A’, ‘B’ and ‘C’ the log shape pattern indicates deposition in a fluvial / tidal, channel environment while for reservoir ‘D’ the pattern indicates deposition in deltaic front environment. Isochore maps computed for horizons ‘A’ and ‘B’, shows that horizon ‘A’ is relatively thick and this pattern suggests increased tectonic activities during deposition of reservoir ‘A’ and is an indication that reservoir ‘A’ is a synrift deposit. Keywords: 3-D Seismic interpretation, Faults, Seismostratigraphy, Well log, Seismic Attributes, Petrophysical parameter

Home country effects of offshoring. A critical survey on empirical literature.

The International fragmentation of production processes is of rising importance. One part of this fragmentation involves the relocation of a production process from a home- to a new host country. This literature survey deals with the effects of such relocations on the home country. First of all, we try to conceptualize the terms and definitions most frequently used in this context which are "outsourcing", "offshore outsourcing" and "offshoring". Despite the fact that there is little textual documentation dealing directly with the phenomena of offshoring and offshore outsourcing we try to give an overview of possible empirical literature to which one can regard to. Including FDI literature we try to cover empirical literature which can provide helpful insight on the effects of a relocation to foreign countries on the home country in connection with wages, skill upgrading, prices, profits, taxes and unions. (author's abstract)Series: Discussion Papers SFB International Tax Coordinatio

Disaster preparedness level in hazard laden environment: A case study of tertiary institution students in Osogbo, Osun State, Nigeria

Objective: The aim was to assess disaster preparedness of tertiary institution students in Osogbo, Osun State.Materials and methods: A cross sectional study carried out among 360 tertiary institution students using a semi structured self-administered  questionnaire.Results: Extreme heat, extreme cold and overcrowding are the hazards commonly exposed to by the students. While some respondents reported  availability of safety equipment in their school, majority do not either have access to it or know how to operate these equipment. About two thirds  (62.5%) are aware of disaster impact while only about one third (33.3%) are highly prepared for it. Bivariate analysis shows that religion (p=0.032), marital  status (p=0.027) and family type (P=0.008) were significantly associated with their awareness level while only program of study (P=0.013) was significantly  associated with preparedness level.Conclusion: Tertiary institution students in Osogbo are exposed to various hazards and majority are not well prepared for it