A review: Intelligent controllers for tropical food storage system

Food security can be assured by improving on post harvest storage methods. Food stored under improper storage conditions are prone to increased respiration and transpiration processes which often result in depletion and weight loss of edible material. Storage temperature and relative humidity are major factors that ultimately determine product quality and quantity. This paper presents a survey on methods of post harvest storage systems. The indigenous methods of tropical food storage common to the West African region are discussed. The attendant problems associated with these methods are highlighted. Intelligent control methods are also discussed. A novel intelligent controller is proposed to sustain product quality and quantity by optimizing the storage process

Comparative Study of Maximum Power Point Tracking with a Modified DC DC Converter

Maximum power points are used to find the voltages and currents at which a photovoltaic (PV) panel should operate to obtain maximum power. In order to deliver highest power, an efficient DC DC converter and a reliable tracking algorithm are used. There is also the need to continuously find the maximum power under any environmental conditions at all times. This research is intended to study a comparative performance of maximum power point (MPP) which is presented under uniform irradiance condition. The algorithm employed is an improved cuckoo search algorithm and the DC-DC Converter( switched mode power supply) has been modified by including a synchronous rectifier connected to a load, the performance of the system is validated using MATLAB/Simulink and practical implementation for this work. A comparison of the MATLAB Simulation with the practical implementation of MPP is presented using maximum power and percentage tracking efficiency as performance metric. From the MATLAB results obtained, maximum extracted power is 26.81W and the hardware implementation gives a maximum power of 28.71W. Tracking efficiency improves by 6.62%. The results show the practical MPP gives a better maximum power, which consequently improves the Photovoltaic systems efficiency and conversely mitigates the power consumption and the cost of the system than the simulation result obtained in MATLAB

The CAST Time Projection Chamber

One of the three X-ray detectors of the CAST experiment searching for solar axions is a Time Projection Chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity X-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is safely set during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62 %. Shielding has been installed around the detector, lowering the background level to 4.10 x 10^-5 counts/cm^2/s/keV between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion-photon coupling and mass.Comment: 19 pages, 11 figures and images, submitted to New Journal of Physic

Bim: the setback or solution to project cost issues in Malaysia construction industry?

Malaysia is progressing into Industry Revolution (IR) 4.0 which emphasizes more onto digital, data and artificial intelligence where everything is expected to be automated. However, cost tends to be a major issue at the pioneer stage of embracing technology where Building Information Modelling (BIM) for example tends to be a cost tussle for the current construction industry. Yet, research has shown that BIM is arguably one of the technology platforms in combating the costing issue considering that BIM enables 3D model elements to link to cost and auto-generate quantities which potentially achieve cost-effective project. Due to the conflicting perspectives of how BIM affects project cost issues, it is imperative to investigate the cost-related issues in implementing BIM in the project and to determine how BIM in general positively influences the overall project cost. Qualitative research is adopted in this study. A semi-structured interview was conducted among four professionals who employs BIM in their project. They consist of the assistant manager, senior manager and chief executive officer. The data collected is analysed by utilising Matrix Table for better organisation. The scope of the study is in the Selangor state in which the local construction industry had applied BIM in their construction industry up to the 3D stage. The results showed that the BIM implementation cost is not too burdensome as it is only a one-time cost and does not vary throughout the project period. In addition, the BIM influence on the overall cost of the project is beneficial to the industry. It improves workflow and cost management. In conclusion, BIM is beneficial to the construction industry in the long term. It is important to resolve the costrelated issues for implement BIM and hence, encourage the usage of BIM, especially in the IR 4.0 ecosyste

May Measurement Month 2017: an analysis of blood pressure screening results from the United Arab Emirates-Northern Africa and Middle East

Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. May Measurement Month (MMM) is a global initiative aimed at raising awareness of high BP and to act as a temporary solution to the lack of screening programmes worldwide. United Arab Emirates has a young population, but cardiovascular disease (CVD) is the commonest cause of death (40%). Myocardial infarction and stroke occurs at least a decade earlier than in western countries. Previous screening in our young population showed that 85% of the population had at least one CVD risk factor and about 62% of them were unaware of it. An opportunistic cross-sectional survey of volunteers aged ≥18 was carried out in May 2017. Blood pressure measurement, the definition of hypertension and statistical analysis followed the standard MMM protocol. Screening was held in 23 sites such as mosques, sports, and men's/ladies' clubs, airports, parks, shopping malls, work places as well as their residences, and in the public areas of hospitals or outpatient clinics. A total of 6193 individuals were screened during MMM17. The mean age was 39.2 ± 13.1 years. After multiple imputation, 1867 (30.2%) had hypertension. Of individuals not receiving anti-hypertensive medication, 813 (15.8%) were hypertensive. Of 1054 individuals receiving anti-hypertensive medication, 427 (40.6%) had uncontrolled BP. MMM17 was a useful screening model as it makes BP measurement easily accessible. Eight hundred and thirteen (16%) possibly new hypertensives were uncovered and 427(40.6%) of those on treatment for hypertension were found to be uncontrolled. These results suggest that opportunistic screening can identify significant numbers with raised BP

General radiographic attributes of optically stimulated luminescence dosimeters: a basic insight

We report the ubiquitous radiographic characteristics of optically stimulated luminescence dosimeters (OSLD) so called nanoDot OSLDs (Landauer Inc., Glendwood, IL). The X-ray irradiations were performed in free air ambiance to inspect the repeatability, the reproducibility, the signal depletion, the element correction factors (ECFs), the dose response and the energy dependence. Repeatability of multiple readouts after single irradiation to 10 mGy revealed a coefficient of variation below 3%, while the reproducibility in repeated irradiation-readout-annealing cycles was above 2%. The OSL signal depletion for three nanoDots with simultaneous irradiation to 20 mGy and sequential readouts of 25 times displayed a consistent signal reduction ≈0.5% per readout with R2 values over 0.98. ECFs for individual OSLDs were varied from 0.97 to 1.03. In the entire dose range under 80 kV, a good linearity with an R2 exceeding 0.99 was achieved. Besides, the percentage difference between OSLD and ion-chamber dose was less than 5%, which was superior to TLD. The X-ray photon irradiated energy response factors (between 0.76 and 1.12) in the range of 40–150 kV (26.1–61.2 keV) exhibited significant energy dependence. Indeed, the nanoDot OSLDs disclosed good repeatability, reproducibility and linearity. The OSLDs measured doses were closer to ion-chamber doses than that of TLD. It can be further improved up to ≈3% by applying the individual dosimeter ECF. On top, the energy dependent uncertainties can be minimized using the energy correction factors. It is established that the studied nanoDot OSLDs are prospective for measuring entrance dose in general radiographic practices

Epidemiological profile of the Ebola virus disease outbreak in Nigeria, July-September 2014

Introduction: In July 2014, Nigeria experienced an outbreak of Ebola virus disease following the introduction of the disease by an ill Liberian Traveler. The Government of Nigeria with the support of Technical and Development Partners responded quickly and effectively to contain the outbreak. The epidemiological profile of the outbreak that majorly affected two States in the country in terms of person, place and time characteristics of the cases identified is hereby described. Methods: Using field  investigation technique, all confirmed and probable cases were identified, line-listed and analysed using Microsoft Excel 2007 by persons, time and place. Results: A total of 20 confirmed and probable cases; 16 in Lagos (including the index case from Liberia) and 4 in Port Harcourt were  identified. The mean age was 39.5 ± 12.4 years with over 40% within the age group 30-39 years. The most frequent exposure type was direct physical contact in 70% of all cases and 73% among health care workers. The total case-fatality was 40%; higher among healthcare workers (46%) compared with non-healthcare workers (22%). The epidemic curve initially shows a typical common source outbreak, followed by a propagated pattern. Conclusion: Investigation revealed the size and spread of the outbreak and provided information on the characteristics of persons, time and place. Enhanced surveillance measures, including contact tracing and follow-up proved very useful in early case detection and containment of the outbreak

A novel and practical screening tool for the detection of silent myocardial infarction in patients with type 2 diabetes

Silent myocardial infarction (MI) is a prevalent finding in patients with type 2 diabetes and is associated with significant mortality and morbidity. Late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) is the most validated technique for detection of silent MI but is time consuming, costly and requires administration of intravenous contrast. We therefore planned to develop a simple and low cost population screening tool to identify those at highest risk of silent MI validated against the CMR reference standard.100 asymptomatic patients with type 2 diabetes underwent electrocardiogram (ECG), echocardiography, biomarker assessment and CMR at 3.0T including assessment of left ventricular ejection fraction and LGE. Global longitudinal strain (GLS) from 2 and 4 chamber cines was measured using feature tracking.17/100 patients with no history of cardiovascular disease had silent MI defined by LGE in an infarct pattern on CMR. Only 4 silent MI patients had Q waves on ECG. Patients with silent MI were older (65 vs 60, p=0.05), had lower E/A ratio (0.75 vs 0.89, p=0.004), lower GLS (-15.2% vs -17.7%, p=0.004) and higher NT-proBNP (106ng/L vs 52ng/L, p=0.003). A combined risk score derived from these 4 factors had an area under the receiver operating characteristic (ROC) curve of 0.823 (0.734-0.892), P<0.0001. A score of ?3/5 had 82% sensitivity and 72% specificity for silent MI.Using measures that can be derived in an outpatient clinic setting, we have developed a novel screening tool for the detection of silent MI in type 2 diabetes. The screening tool had significantly superior diagnostic accuracy than current ECG criteria for the detection of silent MI in asymptomatic patients