Fish farm management and microcontroller based aeration control system

Fisheries are required to grant convenient environmental conditions for fish growth with minimum cost afford.  Providing these environmental conditions should essentially correlate fish type, pond dimensions, water properties, and weather conditions to the fish growth rate, feeding and metabolism.  The large uncertainty margin of such parameters relations and effects drives the farmers to have economically inefficient practices in their farms.  The present work was divided into two parts.  The first part introduced an interactive Microsoft Excel spreadsheets as a decision support system (DSS) for the purposes of fish farm area planning according to the different required purposes of ponds, water evaluation to insure the most suitable environment of fish growth, and mechanical aeration management.  The design of this DSS took the simplicity of required input data and data output into consideration.  The second part was a microcontroller based open loop control system for mechanical aeration process based on the calculations of the DSS.  The aeration management part input and output data fed to the control system with a specially developed program using µC-language.  This program performs the calculations of aeration requirements and energy demands based on the DSS calculations.  Furthermore, the controller had the feature of working from isolated power supply or in collaboration with renewable energy system.  These utilities have been created to be suitable for three fish types, which are Mullet, Tilapia, and Carp fish.  These types have a wide acceptance in the aquaculture activities under warm water conditions.  The data obtained from the calculations of the spreadsheet under simulated and real field conditions were compared to a reference data. The spreadsheet showed an agreement with the reference values.  The control systems succeed to operate 1hp-3phase induction motor for a time that was identical to the required aeration time calculated through the DSS.  It was recommended to rely on the created DSS and the control system for farm area planning, water environment evaluation, and mechanical aeration management and operation.  In addition, improvements for the control system should be carried out to be a real-time system especially with water quality parameters considering system power requirements and operating costs.   Keywords: control system, fish farm, management, microcontroller, aeration

BACH ARRAY LINEAR GENERATOR FOR WAVE ENERGY CONVERTERS

linear generators have been proposed as a proper power takeoff system for direct-drive wave energy conversion. Coupled directly to a reciprocating wave energy device, it was declared that linear generators could be a valuable replacement for hydraulic and pneumatic systems. In this paper, the design and performance evaluation of permanent magnet linear generator that implements Halbach array arrangement is established. The designed generator is suitable for direct energy extraction from sea waves at small wave amplitude. The electromagnetic design is performed using finite element method and space harmonic analysis. A comparative study is performed between Halbach array and conventional air-cored linear generators to show the effectiveness of the proposed design. The equivalent circuit based model is utilized to investigate the dynamic performance of the Halbach array generator. The simulated dynamic performance of the designed generator clarifies that the implementation of Halbach array arrangement would improve energy extraction and voltage waveform

Coupled Particle Transport and Pattern Formation in a Nonlinear Leaky-Box Model

Effects of particle-particle coupling on particle characteristics in nonlinear leaky-box type descriptions of the acceleration and transport of energetic particles in space plasmas are examined in the framework of a simple two-particle model based on the Fokker-Planck equation in momentum space. In this model, the two particles are assumed coupled via a common nonlinear source term. In analogy with a prototypical mathematical system of diffusion-driven instability, this work demonstrates that steady-state patterns with strong dependence on the magnetic turbulence but a rather weak one on the coupled particles attributes can emerge in solutions of a nonlinearly coupled leaky-box model. The insight gained from this simple model may be of wider use and significance to nonlinearly coupled leaky-box type descriptions in general

Technical and Economical Investigation of Renewable Energy Sources for Supplying Offshore Oil production Facilities at Gulf of Suez Area

The Gulf of Suez is highly susceptible to economic and energy security due to the heavy need for imported fossil fuels. The energy produced from fossil fuels causes serious environmental pollution. So, it is important to find other clean sources of energy for stabilizing the released amount of carbon dioxide. Gulf of Suez has the potential to develop clean Solar Photovoltaic (PV) and wind systems to improve economic and environmental performance. This paper proposes a combination of floating solar panels (FSP) and offshore wind turbines to solve the main critical issues, such as the land area required for a large number of cells and the space required for wind turbines. In addition to their good economical and environmental benefits. A simplified model is provided to investigate the replacement of traditional generating units (Diesel and Gas operated) supplying offshore oil production field facilities at the Gulf of Suez area with a mix of renewable resources. The load flow analysis is carried out for the model and the cost is calculated and compared for four schemas, the traditional generating, Wind-Gas, PV-Gas, and PV-Wind-Gas hybrid system. From the techno-economic analysis and comparing environmental benefits, floating solar systems and offshore wind turbines can provide a good solution to the existing problems of energy needs with environmental impacts considered

Optimal Sizing of Standalone PV-Wind Hybrid Energy System in Rural Area North Egypt

This paper studies the sizing of stand-alone renewable energy system applied in rural areas in the north of Egypt. The available renewable energy sources in these areas are investigated to be integrated to supply the different types of electrical loads. The quality and quantity of these sources over various weather and climate changes are studied to construct a robust energy system. The load demand in such areas is determined according to all activities require electrical energy. This study considers the different economic levels and technologies which affect the load demand value. The technique and economical indices required to obtain the optimal are investigated and applied in the various estimated cases. The genetic algorithm (GA) technique is applied to determine the size and number of photovoltaic panels and wind turbines. The obtained solution takes into account the loss of power supply probability and the minimization of system cost. This study presents an essential phase in the sustainable development of such rural areas

Studies of the Precipitation Pattern of Paclitaxel in Intravenous Infusions and Rat Plasma Using Laser Nephelometry

Cremophor EL (CrEL) is commonly used to solubilize paclitaxel (Ptx); a widely established anticancer agent used against many types of cancer. Using laser-based microplate nephelometry, in this work we assessed the precipitation kinetics of Ptx in CrEL-containing formulations upon dilutions with different infusion media or upon introduction into rat plasma. The precipitation profile of Ptx was assessed for a Taxol-like formulation and compared with a preparation with reduced CrEL content. These two formulations were diluted at various ratios in compatible infusion media and with or without rat plasma. The percentages of Ptx precipitated in dilution media and protein-binding in plasma were quantified using HPLC. The findings of turbidity measurements were in good agreement with HPLC. Despite the presence of albumin, it was possible to assess turbidity within infusion solutions and predict Ptx precipitation. Upon addition to plasma, no precipitation in Taxol-like formulation occurred after 2 h. In contrast, precipitation occurred immediately in CrEL-reduced formulation. It is possible that the high percentage of protein-bound Ptx in plasma (98.5–99.2%) has inhibited drug precipitation. Turbidity measurements using laser nephelometry can provide a rapid screening tool when developing intravenous formulations for poorly soluble drugs, such as Ptx and assess its stability upon dilution in animal plasma

Enhanced low voltage nonlinearity in resonant tunneling metal–insulator–insulator–metal nanostructures

The electrical properties of bi-layer Ta2O5/Al2O3 and Nb2O5/Al2O3 metal–insulator–insulator–metal nanostructures as rectifiers have been investigated. The ultra-thin (1–6 nm) insulator layers were deposited by atomic-layer deposition or rf magnetron sputtering with Al as metal contacts. Variable angle spectroscopic ellipsometry was performed to extract the optical properties and band gap of narrow band gap insulator layers while the surface roughness of the metal contacts was measured by atomic force microscopy. Superior low voltage large signal and small signal nonlinearities such as asymmetry of 18 at 0.35 V, rate of change of non-linearity of 7.5 V�1, and responsivity of 9 A/W at 0.2 V were observed from the current–voltage characteristics. A sharp increase in current at �2 V on Ta2O5/Al2O3 device can be ascribed to resonant tunneling

Multivariate epidemiologic analysis of type 2 diabetes mellitus risks in the Lebanese population

Background: The burden of diabetes in Lebanon requires well-targeted interventions for screening type 2 diabetes mellitus (T2DM) and prediabetes and prevention of risk factors. Newly recruited 998 Lebanese individuals, in addition to 7,292 already available, were studied to investigate the prevalence of diabetes, prediabetes and their associated risk factors. Methods: Participants had fasting blood sugar and glycohemoglobin tests in addition to a lipid profile. Clinical and demographic information were obtained from a detailed questionnaire. The relationship between T2DM, its risk factors, and its complications were tested. Comparisons of these risk factors among diabetics, healthy, and coronary artery disease (CAD) patients were performed. Results: The prevalence of T2DM significantly increased with increasing BMI (p < 0.0001). Exercise activity level negatively correlated with the disease (p = 0.002), whereas the prevalence of T2DM (p < 0.0001) and CAD family history (p = 0.006) positively correlated with the affection status. The mean levels of triglycerides and LDL-C were significantly higher in diabetics (1.87; 1.35) compared to individuals with prediabetes (1.63; 1.26) and unaffected controls (1.49; 1.19). People with T2DM showed a significant decrease in HDL-C levels. A strong correlation of overall hyperlipidemia with the diabetes affection status was shown (p < 0.0001). Other comorbid factors such as hypertension (p < 0.0001) and self-reported obesity (p < 0.0001) were highly associated with T2DM and prediabetes. Reproductive health of women showed a strong correlation between giving birth to a baby with a high weight and the occurrence of T2DM and prediabetes later in life (p < 0.0001). Retinopathy and peripheral neuropathy were significantly correlated with diabetes and prediabetes (p < 0.0001). Conclusions: The present study shows an alarming prevalence of diabetes and prediabetes in the studied subgroups representative of the Lebanese population. Electronic supplementary material The online version of this article (doi:10.1186/1758-5996-6-89) contains supplementary material, which is available to authorized users