Modal Space Controller for Hydraulically Driven Six Degree of Freedom Parallel Manipulator

This paper presents the Modal space decoupled control for a hydraulically driven parallel mechanism has been presented. The approach is based on singular values decomposition to the properties of joint-space inverse mass matrix, and mapping of the control and feedback variables from the joint space to the decoupling modal space. The method transformed highly coupled six-input six-output dynamics into six independent single-input single-output (SISO) 1 DOF hydraulically driven mechanical systems. The novelty in this method is that the signals including control errors, control outputs and pressure feedbacks are transformed into decoupled modal space and also the proportional gains and dynamic pressure feedback are tuned in modal space. The results indicate that the conventional controller can only attenuate the resonance peaks of the lower eigenfrequencies of six rigid modes properly, and the peaking points of other relative higher eigenfrequencies are over damped, The further results show that it is very effective to design and tune the system in modal space and that the bandwidth increased substantially except surge (x) and sway (y) motions, each degree of freedom can be almost tuned independently and their bandwidths can be increased near to the undamped eigenfrequencies

Determination of The Major Challenges of Compliance to Set Standards for Establishment of Petroleum Filling Stations in Anambra State

Considering the high level of non-compliance of petroleum filling stations to the set standards by DPR, NESREA and the Anambra State Physical Planning Board/Local Authorities, this study emerged to determine the major challenges of compliance to set standards for establishment of petroleum filling stations by the petroleum filling stations in Anambra State.  This study adopted the survey research design. This involved the use of well-structured questionnaire(s) to generate data by ascertaining first-hand information from the general public (non-professionals) and professionals in town planning and development control. 60 professionals and 400 households were sampled. The mean cut-off of 3.0 was calculated from the adopted 5-point likert scale to ascertain the major challenges. After harmonizing the opinion of the Professionals with those of the general public (Non-Professionals), the main challenges to compliance with set standards in the study area were found to include the following: Scarcity of land, Fear of relocation from original business site, Construction or expansion of roads after the petrol station has been constructed, Competition for business sites/spaces, High cost of land, Difficult land acquisition processes, Corruption of law enforcement agents, Improper urban planning, Ignorance of the after effects of activities by the developers, Failure of the Government to properly monitor activities of the filling stations and Godfathering and inequity in enforcing the set standards. The study thus recommended that: there should be strict monitoring of the development control practices and agencies by the government; Scaling down the requirements to be met by developers before land is acquired to aid easy relocation in the case of business expansion will aid compliance; review of standards that are inconsistent with the present day need of urban development will make the present day developers more compliant to these standards. Also ensuring free and fair judgment on all concerned regardless of who owns the petroleum filling station or who is involved (primacy to the rule of law), will restore discipline and enhance compliance. KEYWORDS: Challenges of compliance, set standards for establishment of petroleum filling stations. DOI: 10.7176/JEES/10-2-10 Publication date: February 29th 202

Awareness and Perception of Climate Change among Farmers in Nigeria: Implications for Food Security

Nigeria is characterized by high level of hunger, malnutrition and poverty, making food security a serious concern in the country. This is being worsened by threats of climate change which adversely affect agriculture; the predominantly livelihood activity in the country. The study examined the implications for food security of farmers’ awareness and perception of climate change in Nigeria using evidence from farmers in Ebonyi State. Multistage random sampling technique was used to select 360 respondents for the study, while data were collected using structured questionnaire. Analysis of data involved the use of frequencies, percentages, means and rating scale, while the results were presented using charts, tables and graphs. The mean extent of knowledge of the farmers of climate change phenomenon is 2.74. About 16.1% of the respondents indicated knowledge to a great extent, 36.4% to a reasonable extent, 26.4% to a little extent, and 21.1% to no extent. Climate change is largely understood by 93.6% of the farmers as fluctuations in average weather conditions. The farmers are being impacted by climate change through increased weather uncertainties (3.71), reduced cropping season (3.60), decreased soil fertility and farm yield (3.48), early cessation of rains (3.33), delayed onset of rains (3.20) and increased temperature (2.89). Their sources of information on climate change are radio (66%), friends and relatives (56.2%), family (33.4%), personal observations (40%), social media (23%), extension agents (21.6%), internet (19%), cooperatives (12.1%) and religious bodies (10%). The study recommends the strengthening of agricultural extension system to engage in increased and continuous sensitization and education of farmers on climate change through radio, social media, internet, cooperative societies and religious organizations

ADOPTION AND UTILIZATION OF EFFECTIVE CONFLICT MANAGEMENT STRATEGIES FOR PROMOTING PEACE-CULTURE IN SECONDARY SCHOOLS IN ANAMBRA STATE, NIGERIA

The aim of this study is to investigate Principal’s adoption and utilization of effective conflict management strategies for promoting peaceculture in secondary schools in Anambra State. The study adopted descriptive survey design. Two research questions guided the study and two null hypotheses tested at 0.05 level of significance were formulated for the study. The population of the study consisted of 254 principals and 254 vice principals (Administration) in the public secondary schools of Anambra State. Data were collected using a 22-item questionnaire. The questionnaire was validated by three experts. For the reliability of the instrument, a coefficient value of 0.86 was obtained and was considered satisfactory for the study. Mean and standard deviation were used in answering the research questions. The t-test was adopted in testing the hypotheses at 0.05 level of significance. The findings revealed that principals did not adopt a considerable number of effective conflict management strategies in schools. Also, the extent to which they utilized effective conflict management strategies in building peace-culture was low. It was thus recommended among others, the principals as a matter of urgency should be exposed to the necessity of adopting all the effective conflict management strategies. This should be done through conferences and seminars if the aim of building peace in secondary schools would be achieved

Comparative Analysis of the Soil Geotechnical Characteristics of the Failed and Unfailed Sections of the Onitsha-Enugu Expressway, Southeastern Nigeria.

This work compared the soil geotechnical characteristics of the failed sections of the road and that of the un-failed sections of the road to establish whether they are significantly different or related. To achieve this, soil samples from both failed and un-failed sections of the road were analyzed. The data so generated, were tested using Correlation Coefficient for relationship and Students T-test for difference. It was found that there exist insignificant relationship between the failed and the un-failed sections of the road, there is significant difference between the two variables and there is wide discrepancies between the geotechnical characteristics of the failed sections and the standard of soil geotechnical characteristics set by the Federal Ministry of Works for highway sub-grades.  It was therefore concluded that the road failure was due to poor geotechnical characteristics of the soil. The work recommended that the variation in the geotechnical characteristics of the soils along the roadway should be accommodated during reconstruction. Sequel to this, knowledge of soil geotechnical characteristics and underlying geology of an area becomes indispensable before any construction, reconstruction or rehabilitation project commences.

Vertical Velocity of Pollutants through Porous Rocks of Anambra State: Implications for Water Resources Planning and Management

Indiscriminate siting of human activities has become a common practice in Anambra State, resulting to generation of mobile pollutants. To this effect, an infiltrometer was used to investigate the velocities of pollutants (four fluids) through five sedimentary formations of varying lithological characteristics, with a view to proffering efficient strategy for management of groundwater resources in the area. A purposive/judgmental sampling technique was used to select the formations used. The study tested the following hypotheses:(i) the velocity of pollutants through rocks is not related to the lithological characteristics of the underlying rocks and (ii) pollution level (densities of pollutants) is not related to the vertical infiltration (velocity) of pollutants. The following findings were recorded: (i) the velocity of pollutants through rocks is closely related to the lithological characteristics of rocks, including porosity and hydraulic conductivity, (ii) pollution level (densities of pollutants) is weakly related to vertical infiltration of pollutants. Consequently, the study recommended that the lithological characteristics of underlying formations should be known before selecting such sites for human activities that generate pollutants so as  to safeguard the groundwater resources of the area. This is to say that shale terrains or any other formations that have, at most, porosity and hydraulic conductivity values of 18% and 2.3 x 10-8 cm/sec. respectively, should be used for human activities that generate mobile pollutants. It also recommended that site selection for various wide scales human activities that generate mobile pollutants should be based on the knowledge of underlying geology of the place in question, and not merely on the availability of such space and close proximity to users. Further research areas were also recommended. Keyword: Pollutants, porous rocks, groundwater, lithological characteristics and managemen

Syntheses, Characterization, and Antimicrobial Screening of N-(benzothiazol-2-yl)-2-nitrobenzenesulphonamide and its Cu(I), Ni(II), Mn(II), Co(II) and Zn(II) Complexes

N-(benzothiazol-2-yl)-2-nitrobenzenesulphonamide (NBS2ABT) was synthesized by the condensation of 2-aminobenzothiazole and 2-nitrobenzenesulphonylchloride under reflux. Five metal complexes of Cu(I), Ni(II), Mn(II), Co(II) and Zn(II) of the ligands were synthesized. The compounds were characterized using magnetic susceptibility measurements, mass spectrometry, elemental microanalysis, UV/VIS spectrophotometry, infra red, 1H and 13C nmr spectroscopies. The antimicrobial tests of the ligands and its metal complexes were carried out on both multi-resistant bacterial strains isolated under clinical conditions and cultured species using agar-well diffusion method. The multi-resistant bacterial strains used were E. coli, Proteus species, P. aeroginosa and S. aureus which were isolated from dogs. The culture species were P. aeruginosa (ATCC 27853), E. coli (ATCC 25922), S. aureus (ATCC 25923), and the fungi, C. krusei (ATCC 6258) and C. albicans (ATCC 90028). The tests were both in vitro and in vivo. The antimicrobial activities of the compounds were compared with those of Ciprofloxacin and trimethoprim-sulphamethoxazole as antibacterial agents and Fluconazole as an antifungal drug. All the compounds showed varying activities against the cultured typed bacteria and fungi used. The Lethal Concentration (LC50) ranged from 5.00±0.86-618.90±30.8 ppm. These are within the permissible concentrations. Key words: N-(benzothiazol-2-yl)-2-nitrobenzenesulphonamide, Metal complexes, Antimicrobial, Ligan

Variability and Heritability of Yield and Yield Components of Various Rice (Oryza sativa L.) Varieties in Port Harcourt, Nigeria

Field experiments were conducted at the Rivers State University Teaching and Research Farm Nkpolu, Port Harcourt, during the 2019 planting season under rainfed condition and complimented by irrigation in two different planting dates to access the genetic variability and heritability in yield and yield components of twenty-five rice varieties. The experiments were laid out in a randomized complete block design with three replications. Data were collected on eleven yield and yield components. Results from the analysis of variance indicated significant differences (P < 0.01 < 0.05) among the varieties for all parameters except plant height and tiller number in planting date one. Combined analysis of variance across planting dates showed that there was significant variation (P < 0.01) among the rice varieties for all parameters evaluated. The varietal mean performance for phenological parameters showed significant differences (P < 0.05) for all parameters except tiller number in planting date one. Variability evaluation of varieties for yield parameters showed significant differences (P < 0.05) for all parameters evaluated except for 100-grain weight in planting date two. The pooled mean values of the varieties differed significantly (P < 0.05) for all yield parameters evaluated. The highest grain yield per stand was recorded in UPIA 2 with 7.41 g/stand, and was significantly different from FARO 67 with the least (1.70 g/stand). The estimate of variance components showed that phenotypic variance (Vp) and phenotypic coefficient of variation (PVC) were higher than their corresponding genotypic variance (Vg) and genotypic coefficient of variation (GCV) for all the parameters studied. Heritability estimates in broad sense were found to be moderate for majority of the parameters, except leaf area (68.12%), panicle number (63.41%), spikelet fertility (50.23%) and grain yield per stand (55.87%) that had high heritability estimates and tiller number (15.93%) which had a low estimate. However, only leaf area, panicle number and grain yield per stand had high heritability estimates which were accompanied by high genetic advance. There was considerable variation among the 25 rice varieties evaluated. UPIA 2 and FARO 44 had the best agronomic performance. However, UPN 324, UPN 228, FARO 61 and 66 could be selected for onward improvement programme. Keynote: Grain yield, heritability, Oryza sativa, variation, yield components DOI: 10.7176/ALST/86-04 Publication date:March 31st 202

Haematological changes due to bovine fascioliasis

This study determined the haematological changes due to the infection of fascioliasis in cattle. The haematological indices of blood samples collected from purposely selected Fasciola-infected and noninfected cattle were analyzed using standard methods. Statistical analysis revealed high significant differences between the packed cell volume (PCV), haemoglobin (Hb) and red blood cells (RBC) of infected and non-infected cattle (p<0.05). Significant differences existed between the white blood cells (WBC), mean cellular volume (MCV) and mean cellular haemoglobin (MCH) of both groups (p<0.05). No significant difference was observed between the mean cellular haemoglobin concentration (MCHC) of the infected cattle and the control. There was notable reduction in PCV, Hb and RBC with increase in worm load and a multiple regression analysis revealed significant negative correlation between worm load and RBC, Hb and PCV with correlation coefficient values, r = -0.616, -0.592 and -0.615, respectively. Levels of neutrophils, eosinophils, monocytes and lymphocytes increased progressively as worm load increased. Only basophils showed no change. Multiple regression analysis confirmed a statistically significant positive correlation between eosinophils and worm load (r = 0.575) and between neutrophils and worm load (r = 0.601). Lymphocytes had no significant positive correlation with worm load (r = 0.070), while monocytes had no significant negative correlation with worm load (r = - 0.062). The implications of the above findings are discussed.Keywords: Fascioliasis, haematology, haemoglobin, neutrophils, eosinophils, monocytesAfrican Journal of Biotechnology Vol. 12(15), pp. 1828-183