Thermodynamic optimization tools for power tracking in a multistage concentrated solar power Rankine plant

Abstract: The object of the study is to present a method of thermodynamic optimization of power generating plants, in a mode that consolidates and simplifies the analysis of data on heat-work interaction of the plant components. The optimization scheme identifies the technical and process parameters that can improve the thermodynamic performance of the plant with respect to an objective variable, and further, the required thermodynamic measures necessary to improve the operating condition of the plant. Simple but effective tools are used to evaluate the optimal and suboptimal power generating capacities vis-à-vis the fundamental variables—namely, the thermodynamic quantity ratio (TQR) and the power-energy quantity ratio (PQR)—without routing optimization procedures. Beyond the optimal value of the objective variable, the power generation capacity of the plant is affected. The determination of the optimal value of the objective variable can also be approached by computerization; for fixed prescriptions of the boiler, superheater, and turbine parameters, variables such as boiler pressure and temperature can be optimally selected. DOI: 10.1061/(ASCE)EY.1943-7897.0000367. © 2016 American Society of Civil Engineers

Inflation and economic growth relationship in the West African Monetary Zone

Inflation and output growth relationship is of interest to policymakers and researchers. In the West African Monetary Zone, the attainment of low inflation rate is considered as one of the convergence criteria for the successful implementation of monetary union in the zone. Although there has been empirical evidence that the relationship between inflation and output growth in the WAMZ is non-linear, the question yet to be answered is, “at what level is inflation detrimental to economic growth?” This paper extends the link of analysis by investigating the optimal inflation for the WAMZ countries using the quadratic approach to threshold estimation. The findings drawing from economic theory and analysis suggests that inflation rate in the WAMZ is significantly associated with lower growth only after it reaches 12.86 percent. The result further indicates that there are significant differences in the inflation threshold levels in the WAMZ countries. The findings of this research are not surprising given the institutional features and structure of the different countries in the zone. The findings of the research suggest that monetary authorities in the WAMZ countries could accommodate inflation rate up to the threshold level, even when that is higher than what is currently being targeted in the zone, so as not to stifle growth in the area. Also, although the WAMZ countries belong to the same geographical area, which could enhance group formation; there could be other sources of heterogeneity like different political, legal, economic, and national policies that drive individual growth processes in the zone.Central Bank of Nigeri

Multimedia Object Modelling and Storage Allocation Strategies for Heterogeneous Parallel Access Storage Devices in Real Time Multimedia Computing Systems

The improvements in disk speeds have not kept up with improvements in processor and memory speeds. Conventional storage techniques, in the face of multimedia data, are inefficient and/or inadequate. Here, an efficient multimedia object allocation strategy is presented. We describe a multimedia object model, the object and storage device characteristics, and the fragmentation strategy. A bipartite graph approach is used for mapping fragments to storage devices and a cost function is used to determine an efficient allocation of an object and to balance the loads on the devices

Phyto-nutrient composition and antioxidative potential of ethanolic leaf extract of Sida acuta in wistar albino rats

Phytochemical, micronutrient composition and anti-oxidative potential of ethanolic leaf extract of Sida acuta in albino wistar rats were investigated using standard analytical methods. The result (mg/100 g) for phytochemical composition were 91.46 ± 0.02 tannin, 1500.36 ± 0.36 alkaloid, 530.27 ± 0.03 saponin, 1163.86 ± 0.1 flavonoid, 1454.50 ± 0.85 steriod, 115.29 ± 0.05 terpeniods and 851.62 ± 0.01 cardiac glycosides. The vitamin composition (mg/100 g) were 0.36 ± 0.01 thiamin, 0.19 ± 0.02 niacin, 24.27 ± 0.25 ascorbic acid, 1.85 ± 0.32 tocopherol, 0.12 ± 0.05 riboflavin while mineral composition (mg/100 mg) was 14428 ± 0.02, 122.11 ± 0.01, 325.12 ± 0.02 for calcium, magnesium and zinc, respectively. To determine the antioxidative potential, twenty-four adult wistar albino rats were divided into four groups of 6 rats each. Group 1 received feed and water (control) while group 2, 3 and 4 in addition to feed and water were treated with ethanol leaf extract of S. acuta at 20, 40 and 60 mg/kg body weight, respectively. After 14 days of treatment; the rats were sacrificed and plasma obtained for oxidative stress indices assay. The result showed a significant decrease (P < 0.05) in mean values of plasma malondialdehyde concentration and a significant increase (P < 0.05) in reduced glutathione concentration at 40 and 60 mg/kg body weight compared to the control group. Plasma catalase and superoxide dismutase activity were significantly increased (P < 0.05) only in animals treated with 60 mg/kg body weight compared to the control group. The result showed that ethanolic leaf extract of S. acuta possesses an antioxidant property which, in a dose dependent manner, reduces/ameliorates oxidative stress in rats.Keywords: Sida acuta, rats, micronutrients, phytochemical, oxidative stres

Protective role of Phyllantus niruri extract on serum lipid profiles and oxidative stress in hepatocytes of diabetic rats

Diabetes mellitus has been associated with lipid abnormalities and oxidative stress. Some phytochemical properties have been shown to possess antioxidant activities, improving the effects of oxidative stress on diabetes. This present investigations confirmed that untreated diabetic rats were associated with lipid abnormalities as indicated by high levels of total- and LDL-cholesterol, triacylglycerols and low levels of HDL-cholesterol and phospholipids, compared to non-diabetic rats(control). The aqueous extract of Phyllanthus niruri significantly normalized the serum lipids levels. The study also showed that untreated diabetic rats were subjected to oxidative stress as indicated by significantly abnormal activities of their scavenging enzymes (superoxide dismutase and catalase and significantly low levels of non-enzymic antioxidants (vitamin C, vitamin E and reduced glutathione) in liver and plasma when compared with controls and in the extent of lipid peroxidation (increased malondialdehyde levels) in plasma and liver cells. The aqueous extract of P. niruri possessedantioxidant activities as shown by increased activities of enzymic and non-enzymic antioxidants and decrease in malondialdehyde levels

Digital Therapeutics for Mental Health: Is Attrition the Achilles Heel?

Digit therapeutics are novel software devices that clinicians may utilize in delivering quality mental health care and ensuring positive outcomes. However, uptake of digital therapeutics and clinically tested software-based programs remains low. This article presents possible reasons for attrition and low engagement in clinical studies investigating digital therapeutics, analyses of studies in which engagement was high, and design constructs that may encourage user engagement. The aim is to shed light on the importance of real-world attrition data of digital therapeutics, and important characteristics of medical devices that have positively influenced user engagement. The findings presented in this article will be useful to relevant stakeholders and medical device experts tasked with addressing the gap between software medical design and user engagement present in digital therapeutic clinical trials.Comment: 11 pages, 1 tabl

Oxidative stress and non-enzymic antioxidant status in hypertensive patients in Nigeria

Oxidative stress and non-enzymic antioxidant status in plasma of hypertensive patients in Nigeria were investigated. One hundred and fifty hypertensive patients (82 males and 68 females) age range 55 – 75 years visiting Federal Medical Centre, Owerri were selected for the study. Controls were 120 apparently healthy subjects (66 males and 54 females) age range 55 -75 years. Patients with complication such as renal diseases, viral and bacterial infections were excluded from the study. In The hypertensive patients presented significantly higher mean values of plasma total cholesterol, LDL-cholesterol and triacylglycerolsand reduced HDL-cholesterol and phospholipids (p < 0.05). The result of plasma lipid peroxide was significantly higher in hypertensive patients (p < 0.05). Also the levels of non-enzymic antioxidantssuch as Vitamin C, vitamin E and reduced glutathione in plasma were significantly depleted in the hypertensive patients (p < 0.05). This study shows that hypertension is associated with increasedoxidative stress and depleted non-enzymic antioxidant status even in developing countries like Nigeria

Reconstitution of the Olfactory Epithelium Following Injury in ApoE-Deficient Mice

ApoE, a protein component of lipoproteins, is extensively expressed in the primary olfactory pathway. Because apoE has been shown to play a vital role in nerve repair and remodeling, we hypothesized that apoE expression will increase in the injured olfactory epithelium (OE), and that apoE deficiency in apoE knockout (KO) mice will lead to delayed/incomplete reconstitution of the OE following injury. To directly test this hypothesis, we compared OE regeneration in wild-type (WT) and KO mice following injury induced by intranasal irrigation of Triton X-100. OE was collected at 0, 3, 7, 21, 42, and 56 days post lesion. The amount and distribution of apoE in the regenerating OE was measured by immunoblotting and immunohistochemistry. Rate of OE reconstitution in WT and KO mice was assessed by using three independent measures: (1) OE thickness was measured in cresyl-violet stained sections, (2) basal cell proliferation was determined by using bromodeoxyuridine (BrdU) staining, and (3) differentiation and maturation of olfactory sensory neurons were measured by immunoblotting and immunohistochemical analysis of growth associated protein (GAP) 43 and olfactory marker protein (OMP). The results revealed that apoE expression in the OE is highly regulated during the entire course of OE reconstitution post injury, and that apoE deficiency in apoE KO mice leads to delayed recovery of mature OMP+ cells in the reconstituting OE. The data suggest that apoE production increases in the injured OE to facilitate maturation of olfactory sensory neurons

Slavery in the Contemporary World: An Examination of Modern Slavery in Africa

The paper examines slavery in the contemporary world with focus on examination of modern slavery in Africa. It underscored factors promoting slavery in the modern world, trends of modern slavery, causes of modern slavery in Africa, and consequences of modern slavery in Africa. The Marxian conflict theory was used as a guide and a background upon which the paper was anchored. From the point of view of the theory and available literature reviewed, the paper observed that factors such as population explosion of the post second world war, rapid economic change and the incorporation of the third world economies into the world economy in the guise of globalisation, and the widespread governmental corruption among others, are responsible for modern slavery in Africa and the world over. It revealed that forced labour, sex slavery, practice of debt bondage and trafficking in persons are all characteristics of modern slavery. The significance of this is enormous and antithetical to the development of the continent and humanity at large. The paper recommended that policies on human migration should be reviewed across borders, agencies established to tackle the menace of trafficking in persons should straightened so as to function effectively and efficiently, African countries should make frantic efforts in tackling the issue of corruption and over-dependence on advanced countries of the world. Finally, a radical change in mentality is advised of African citizens on migration

Optimal Analysis of Packaging Products of MAHEU Plant in Intafact Beverages Limited Using GPALS and MATLAB Optimization Software

This work focused on the optimization of the two packaging products; Supershake and Chibuku made up of three and two parts respectively. Copolymer polypropylene and white or colored batch materials are the two raw materials needed to produce the two packaging products. The manufacturing plan was developed for the organization. The production inputs of 1.11, 6.67, 15.78, 2.47 and 7.70 units were generated as the objective function coefficients; 308 hours per month for day shift and 364 hours per month for night shift were established. Production time of 10 seconds, 20 seconds, 12 second, 10 seconds and 12 seconds per unit of the five parts were established. The manufacturing constraints in terms of machine capacities, material availability, time and labour were extensively used to develop an integer linear programming model to obtain the optimum quantities of each part that will yield the maximum profit. The developed model was analyzed with GPALS and MATLAB optimization solver to obtain results for the linear programming model which gave a monthly production net profit of N3,751,932. A decision support system was developed for the manufacturing planning to assist the management of Maheu plant in Intafact Beverages Limited in decision making. The model is now being used in the manufacturing plan of the company and also recommended for application in organizations with similar production inputs. Keywords: Manufacturing plan, Production inputs, Manufacturing constraints,  Optimization, Profit and Decision makin