Artificial Neural Network Model for Low Strength RC Beam Shear Capacity

This research was to investigate how the shear strength prediction of low strength reinforced concrete beams will improve under an ANN model. An existing database of 310 reinforced concrete beams without web reinforcement was divided into three sets of training, validation and testing. A total of 224 different architectural networks were tried, considering networks with one hidden layer as well as two hidden layers. Error measures of strength ratios were used to select the best ANN model which was then compared with 3 conventional design code equations in predicting the shear strength of 26 low strength RC beams. Even though the ANN was the most accurate, it was less conservative compared with the design code equations. A model reduction factor based on the characteristic strength concept is derived in this research and used to modify the ANN output. The modified ANN model is conservative in terms of safety and economy but not overly conservative as the conventional design equations. The procedure has been automated such that when new experimental sets are added to the database, the model can be updated and a new model could be developed

Macroeconomic Interdependence and Integration in Africa

There is a renewed interest in the debate on integration in Africa since the creation of the Africa Union in 2002. This study investigates the feasibility of a full-fledge union in Africa from an economic standpoint. Towards this goal, we examine both the contemporaneous and dynamic relations in the short- and long-run among six key macro variables--consumer price level, gross domestic product, consumption, investment, trade flows and government expenditures--in eight African countries. In the quarterly data from 1976 to 2005, we observe the existence of common trends in real output, price level, private consumption, government consumption, investment and trade flows among these eight countries. In addition, we also note that there exist common cycles in real output, investment and trade flows for these countries. These two critical findings indicate the existence of some macroeconomic interdependence among these countries. Thus, the chances for success of integration in Africa driven by these eight countries are appreciable

Does automation improve stock market efficiency in Ghana?

The automation of the Ghana Stock Exchange (GSE) in 2008, among other reforms, was expected to improve the efficiency of the market. The extent of this truism has, however, not been empirically established for the GSE. In this study, we attempt to assess the impact of the automation on the efficiency of the GSE within the framework of the weak-form Efficient Market Hypothesis (EMH) based on the before and after approach. The study was done both at the aggregate and micro-level. The aggregate result showed that automation of the exchange did not improve the overall efficiency of the exchange. However, there is evidence that the number of market participants involved in the exchange has increased in the post-automation era. The results of the impact of the automation on the effi ciency of the microstructure are, however, mixed. Generally, the rejection of the null hypothesis under homoscedasticity was found to be robust to heteroscedasticity for some firms, but the reverse was the case for other fi rms. This implies that the rejection of the null hypothesis under homoscedasticity is due to both heteroscedasticity and serial correlation. Based on the findings, a mix of strategies aimed at improving the efficiency of the exchange are recommended.Keywords: automation; stock market efficiency; Ghana Stock Exchang

The use of ilizarov external fixator for open comminuted fractures in different parts of tibia

Background: Open fracture of tibia is a common occurrence in the orthopedic treatment arena. Ilizarov technique is a popular technique of treating open tibial fracture after debridement and open reduction. It is comparatively a newer method and has many advantages.Methods: This study was carried out in the department of orthopaedics, Centre for women and child health, Ashulia, Dhaka, Bangladesh during the period from January 2019 to June 2021. In total 30 patients with tibial fractures were selected as the study population. Before starting the intervention, the written consent of the participants was taken and this study was approved by the ethical committee of the respective medical college.Results: Out of total 30 participants, 24 (80%) were males and 6 (30%) were female. In analyzing mode of injuries, we found highest (86.7%) participants were from road accidents followed by 10% from sports injury and the remaining 3.3% from general falls. The duration of treatment with the fixator was 12-23 weeks (average 16 weeks). Fourteen patients wore a PTB cast for an additional period of 4 weeks. In our study total 30 cases were debrided on the same day and stabilized with Ilizarov ring fixator after a period of 5 to 12 days from the date of injury. The operation time ranged from 90 minutes to 120 minutes (Mean 102±4 minutes).Conclusions: No case developed deep infection, non-union or unacceptable mal-union. The construct is stable and enables the patient to bear weight on the affected limb a short time after the surgery, even in cases of comminuted fractures

Currency Substitution in Selected African Countries

This study investigates the presence of currency substitution in eight African countries--Egypt, Morocco, Nigeria, Ghana, Kenya, South Africa, Tunisia and Zambia--for the period 1976 to 2005 using both regional and US dollar as anchor currencies. We find that currency substitution is prevalent in Ghana and Nigeria when CFA franc is used as an anchor currency. However, when US dollar is used as an anchor currency there is no evidence of currency substitution in Ghana but we still observe the presence of currency substitution in Nigeria. Also we find presence of currency substitution in South Africa but not in Egypt when the US dollar is the anchor currency. For Kenya, Tunisia and Zambia there is no evidence of currency substitution irrespective of the anchor currencies considered. In the case of Morocco, we observe no evidence of currency substitution when the Egyptian pound is used as anchor currency but there is weak evidence of currency substitution when the US dollar is considered

Factors Influencing the Green House Gas Footprint of US Dairy Farms

Environmental Economics and Policy, Livestock Production/Industries,

Performance Comparison Between HMLP, MLP And Recurrent Networks With Applications To Carbon Monoxide Concentrations Forecasting.

This paper compares the performance of Hybrid Multilayered Perceptron (HMLP) network, Multilayered Perceptron (MLP) network and Recurrent network. These networks are used to model and forecast carbon monoxide (CO) concentration

Lessons about likelihood functions from nuclear physics

Least-squares data analysis is based on the assumption that the normal (Gaussian) distribution appropriately characterizes the likelihood, that is, the conditional probability of each measurement d, given a measured quantity y, p(d | y). On the other hand, there is ample evidence in nuclear physics of significant disagreements among measurements, which are inconsistent with the normal distribution, given their stated uncertainties. In this study the histories of 99 measurements of the lifetimes of five elementary particles are examined to determine what can be inferred about the distribution of their values relative to their stated uncertainties. Taken as a whole, the variations in the data are somewhat larger than their quoted uncertainties would indicate. These data strongly support using a Student t distribution for the likelihood function instead of a normal. The most probable value for the order of the t distribution is 2.6 +/- 0.9. It is shown that analyses based on long-tailed t-distribution likelihoods gracefully cope with outlying data.Comment: presented at 27th International Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering (Maxent 2007), 10 pages, 12 figure

DIVERSITY OF MICROBIAL STRAINS INVOLVED IN COCOA FERMENTATION FROM SUD-COMOÉ (COTE D’IVOIRE) BASED ON BIOCHEMICAL PROPERTIES

The cocoa pulp fermentation is one of keys step for obtaining a quality chocolate. However, microflora involved in this process is complex and variable that leads to inconsistent production efficiency on cocoa quality. Here we investigate the diversity of microflora implicated in Sud-Comoé (area of Côte d’Ivoire) cocoa fermentation based on their biochemical properties. During fermentation, yeasts, Lactic Acid Bacteria (LAB) and Acetic Acid Bacteria (AAB) reached maximum load at 36, 24 and 72 h respectively and decreased rapidly while the rate of Bacillus load increased throughout the fermentative process to reach a peak at 144 h. Among the Bacillus strains, 62.22, 87.5 and 33.7 % were able to produce pectinolytic enzymes, acid and citrate lyase respectively. Concerning yeasts strains, 25.43 % showed pectinolytic enzymes production capacity and all of these isolates were able to ferment glucose and fructose while 52 % were able to produce gas from sucrose. Population of LAB was predominant by homofermentative group with proportion at 85.96 % while AAB were dominated by genera Acetobacter with 88.78 %. Therefore, this study shows the diversity of biochemical properties of tested microbial strains indicating a diversity of microbiota involved in Sud-Comoé cocoa fermentation