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Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In this work, a laboratory study of enhanced oil recovery (EOR) was carried out using Egyptian crude oil of 37°API extracted from a reservoir in the Western Desert to identify the optimum conditions for the application of locally prepared nanocomposite polymer flooding under harsh reservoir condition. In contrary to the other studies, we tested the ability of nanocomposite polymer where nanoparticles are involved in the polymer matrix during polymerization process. Measurements of viscosity and shear rate of several solutions were taken. Displacement runs were conducted at different conditions of nanocomposite polymer salinities (10,000, 20,000, 30,000, 40,000, 50,000, 60,000 and 65,000 ppm), concentrations (1, 1.5, 2, 2.5, 3, 3.5 and 4 g/L) and slug sizes (0.2, 0.4, 0.6 and 0.8 PV). A linear sandpack (length of 62.5 cm and diameter of 2″) was prepared and wrapped with thermal jacket to simulate several reservoir temperatures. It was filled by selected sand size to produce linear sandpack model with reasonable porosity (22%) and permeability (129–157 mD) values. The model was used to perform several displacements runs for waterflooding and nanocomposite polymer flooding. The results of the flood runs are analyzed using the water–oil relative permeability curves. The measurements of the solutions properties showed that the critical concentration of the used nanocomposite polymer in the solution is 2 g/L. Also, it was observed that the used nanocomposite polymer solution could withstand a salinity of 60,000 ppm. As a result of the flooding, it was found that the optimum economical slug size of the used nanocomposite polymer is 0.4 PV at reservoir temperature of 40 °C. The results indicated also that the used nanocomposite polymer could withstand a reservoir temperature of 90 °C. The water–oil relative permeability curves showed an enhancement of oil relative permeability and a decrease in the water relative permeability using nanocomposite polymer over waterflooding. The cost of the used nanocomposite polymer with a concentration of 2 g/L and slug size of 0.4 PV is 0.626 $ for each barrel of the incremental oil recovery. Based on the results of this work, it is clear that involving nanoparticles such as silica in the polymer matrix composition improves its properties, thermal and salinity resistivity. Such study is an original contribution to carry out successful nanocomposite polymer EOR projects.

In this work, a laboratory study of enhanced oil recovery (EOR) was carried out using Egyptian crude oil of 37°API extracted from a reservoir in the Western Desert to identify the optimum conditions for the application of locally prepared nanocomposite polymer flooding under harsh reservoir condition. In contrary to the other studies, we tested the ability of nanocomposite polymer where nanoparticles are involved in the polymer matrix during polymerization process. Measurements of viscosity and shear rate of several solutions were taken. Displacement runs were conducted at different conditions of nanocomposite polymer salinities (10,000, 20,000, 30,000, 40,000, 50,000, 60,000 and 65,000 ppm), concentrations (1, 1.5, 2, 2.5, 3, 3.5 and 4 g/L) and slug sizes (0.2, 0.4, 0.6 and 0.8 PV). A linear sandpack (length of 62.5 cm and diameter of 2″) was prepared and wrapped with thermal jacket to simulate several reservoir temperatures. It was filled by selected sand size to produce linear sandpack model with reasonable porosity (22%) and permeability (129–157 mD) values. The model was used to perform several displacements runs for waterflooding and nanocomposite polymer flooding. The results of the flood runs are analyzed using the water–oil relative permeability curves. The measurements of the solutions properties showed that the critical concentration of the used nanocomposite polymer in the solution is 2 g/L. Also, it was observed that the used nanocomposite polymer solution could withstand a salinity of 60,000 ppm. As a result of the flooding, it was found that the optimum economical slug size of the used nanocomposite polymer is 0.4 PV at reservoir temperature of 40 °C. The results indicated also that the used nanocomposite polymer could withstand a reservoir temperature of 90 °C. The water–oil relative permeability curves showed an enhancement of oil relative permeability and a decrease in the water relative permeability using nanocomposite polymer over waterflooding. The cost of the used nanocomposite polymer with a concentration of 2 g/L and slug size of 0.4 PV is 0.626 $ for each barrel of the incremental oil recovery. Based on the results of this work, it is clear that involving nanoparticles such as silica in the polymer matrix composition improves its properties, thermal and salinity resistivity. Such study is an original contribution to carry out successful nanocomposite polymer EOR projects. [ABSTRACT FROM AUTHOR]

Hydrogen production from biomass steam gasification is systematically reviewed. Equilibrium modeling and simulation studies using various techniques for effective hydrogen production are presented. Heat integration, economic analysis of the hydrogen production, and systematic design algorithms research publications are overviewed and discussed for energy‐efficient and economic hydrogen production from various biomass feedstocks. Comparison and analysis of the results strongly suggest the viable potential of biomass steam gasification for hydrogen production from small to large scales with applications for thermal heat, power generation, and many other industrial fields. [ABSTRACT FROM AUTHOR]

One of the reasons for the slow conversion program from gasoline to LPG/Vigas is the uncertainty of profit or loss. Therefore, this article presents a simple calculator to assess the feasibility of investing in vehicle conversion, from gasoline to LPG/Vigas. Input parameters include estimated annual mileage, fuel consumption, gasoline prices, LPG / Vigas prices, the cost of the converter kit and its installation, engine standardization costs, maintenance costs with gasoline, and maintenance costs with LPG considered to produce output parameters that include Break Even Point (BEP), Payback period (PP), Net Present Value (NPV), and Internal Rate of Return (IRR).

We studied production costs, factor costs and profitability of shrimp farming in the four southerncoastal provinces of Iran during the year 2000. A comprehensive questionnaire was used for data collection. A number of 144 farms were randomly selected, classified and analyzed. An expert team comprising an economist, statistician and shrimp aqua-culturist completed the questionnaire, while referring to all selected farms. Results showed that shrimp. larvae stocking density averaged 224966 per hectares and the shrimp production averaged 169kglha. On average, food, PL and labour costs per hectare were found to be Rials 10000, 6000 and 2000 respectively. In the year 2000, the average profit for the four provinces of shrimp farming was Rials 9555 per kg. of cultured shrimp. Hormozgan province had the highest profit with Rials 20092 per kg and Khouzestan province had the lowest with Rials 4576 perkg of the cultured shrimp.

The paper reports the use of an open source simulation software called GreenCloud to create a novel Problem Based Learning in a laboratory scale. The actual case of Indonesian government's plan to deploy cloud based data center infrastructure is taken as actual PBL case. Green- Cloud enables the students to apply the case in simulation environment and then perform cloud economics analysis. There are three models of cloud architecture could be simulated namely Two-Tier, Three-Tier and Three-Tier High Speed. In addition, in terms of cloud economics analysis, there are three options available to be chosen, i) non energy savings, ii) Dynamics Voltage and Frequency Scaling (DVFS) and iii) Dynamics Shutdown (DNS). It has been shown that the novel PBL model could benefit learning processes. [ABSTRACT FROM AUTHOR]

This study was conducted at the experimental site in Islamabad, Pakistan, in spring season 2013 (March - July). A randomized complete block design with three treatments and replicated thrice were used in this study, fertilizers were evaluated on the basis of yield, input/output energy of maize crop. NPK had the maximum output energy gain as compared to cow manure and control treatment gave the lowest output energy. Cow manure used high energy as compared to NPK and control. The results further revealed that other NPK fertilizer treatments were affected by the high input costs thus maximum benefits were achieved. It is interesting to note that the NPK treatment appeared to be the best for all farmyard manure and control plots. [ABSTRACT FROM AUTHOR]

There is a substantial increase in the number of street vendors in the major Asian cities. In India, the National Policy for Urban Street Vendors/Hawkers notes that street vendors constitute approximately 2 per cent of the population of a metropolis. Street vendors have an important role in the informal economy by making a significant contribution. Due to the inception capacity of the modern organized sector to provide employment for the rapidly expanding labor force a large number of persons try to create or find income opportunities. Our 25% of the workers globally operate in the informal sector. Due to constant influx of people from the rural areas, the informal economic activities mobilize 30% to 80% of the workforce especially in the urban regions of the devolving countries. The shortage of productive employment opportunities in the informal sector and the employment growth which takes place at a far lower rate compared to the growth in the informal sector is largely attributed to divergence between the growth in urban population and employment growth in-formal economy. The increasing urban population with limited to meet the needs of housing, food and clothing of themselves and their families generates a significant which can be supplied by informal sector vendors. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to empirically analyze the determinants of arable crop farmers’ awareness to causes and effects of climate change in south western Nigeria. Design/methodology/approach – Using primary data, 150 arable crop farmers in Ogun State were selected through a multi stage sampling technique. Survey method was used to elicit information on farmers’ socioeconomic, production characteristics, and their level of awareness to causes and effects of climate change. The data collected were analyzed using descriptive statistics, environmental awareness index (EAI), and Tobit regression analysis. Findings – Most (81.08 percent) of the arable crop farmers were males with an average household size of eight persons, farming experience of 24 years and farm size of approximately 1 ha. The computed climate change EAI showed that only 47 percent of the respondents were aware of causes of climate change, while 68 percent were aware of its effects. Results further revealed that age, income from secondary occupation (p < 0.10), marital status, household size (p < 0.05), years of farming experience, frequency of extension contact, land size in hectare, and farm revenue (p < 0.01) were the determinants of respondents awareness to causes and effects of climate change. Practical implications – The study recommended among others that, awareness should be created among arable crop farmers on climate change causes and effects for appropriate mitigation actions to be taken for improved agricultural productivity. Originality/value – The study provided new empirical evidence on the awareness level of respondents to causes and effects of climate change on their production activities and livelihood in general. Implications for policy will be to provide a public education program that will target females, the poor, the illiterate, and the people in the economically active age group among others in order to create awareness and provide information and adequate knowledge on the causes and effects of climate change for proper mitigation and adaptation options. [ABSTRACT FROM AUTHOR]

The aim of this paper is to illustrate possibilities of using Pareto method in evaluating the effectiveness of engineering production processes. The essence of this issue is dividing materials by using progressive technologies on the specific component and the evaluation of its effectiveness and quality. For the production of component was used method of dividing by the plasma, laser and water jet. To eliminate the irregularities in the quality of the resulting component was used Pareto method. The aim was to determine from the available technical knowledge the most efficient method using established evaluation model of efficiency. The result is the finding that the most effective device for dividing the chosen component is the plasma device. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model equilibrium material flows processes on two nuclear fuel cycle options. [•] Monte Carlo simulation was used to get the statistical results with deviations. [•] We set the time frame to schematically describe the fuel cycle processes. [•] We determined all component costs separately discounted to the base year. [Copyright &y& Elsevier]

An economic analysis of fungicide and fertilizer applications on huckleberry fresh shoot yield was carried out in August- December 2006 and in March-July 2007. Six varieties (SS05.1, S18, SS08, SS19, SS25.1, and SS01), four levels of fertilization (unfertilized, mineral fertilizer (NPK), and 10 and 20 Mg ha-1 of poultry manure), and fungicides were evaluated in a split plot trial. The sub-plots received Ridomil Plus® (12% metalaxyl + 60% cuprous oxide), at a rate of 2.5 kg ha-1 on appearance of first foliar late blight symptoms. Fungicide application reduced late blight severity. Yield increase due to fungicide application was as high as 16.14 Mg ha-1. Fertilizer application increased fresh shoot yields (range: 0.60 to 46.18 Mg ha-1). However, poultry manure application increased both huckleberry yields and late blight infestations. In economic terms, the results showed a maximum benefit of €3494 ha-1due to fungicide application. The net benefit due to fertilizer application varied between €28 and €1514 ha-1 for NPK; €455 and €3120 ha-1 for 10 Mg ha-1 of poultry manure; and €328 and €9258 ha-1 for 20 Mg ha-1 of poultry manure. Variety SS05.1 gave the highest net benefit due to fungicide and fertilizer applications and is therefore recommended where the pesticides are available. Variety SS25.1 is resistant to late blight and high yielding and therefore could be cultivated without fungicides, with or without fertilizers. [ABSTRACT FROM AUTHOR]

Taura Syndrome Virus (TSV) and White Spot Syndrome Virus (WSSV) have significantly decreased survival rates of farm-raised penaeid shrimp in Honduras and other shrimp-growing regions of the Western Hemisphere. A dataset of individual records of 1,004 shrimp ponds in Honduras was used to develop a linear programming model to evaluate optimal management strategies if viral disease prevention programs were implemented on shrimp farms. The model selected low and intermediate stocking densities as optimal for most growout cycle alternatives considered given post-Taura and post-White Spot Syndrome production relationships. Model simulations indicated that the decreased shrimp survival due to viral infections had decreased net farm income by approximately 84% from optimal management plans in the absence of viral diseases. Simulations in which costs of viral disease prevention programs were included resulted in a 47% increase in net farm income above the base scenario. Production activities would need to be re-scheduled and stocking densities adjusted to accommodate disease prevention programs. These results further provide a measure of the value to shrimp farms of new technologies related to either shrimp health or disease-resistant shrimp that increase shrimp survival rates. [ABSTRACT FROM PUBLISHER]

This paper describes an advanced multibeam communications satellite system using on-board processing and hopping beams in conjunction with low-cost earth-stations to derive a significant advantage over fibre optic submarine cable. It serves thousands of small earth-stations located near the origins of traffic. An economic analysis is presented for both this satellite system and competitive fibre optic cable for the 1995 to 2007 epoch. Results indicate the satellite service to be significantly lower in cost, and in addition it delivers the service near to the origin of the traffic, providing additional savings in terrestrial connections. [ABSTRACT FROM AUTHOR]

Solar thermal-powered desiccant dehumidification systems are attracting attention for cooling load-dominated climates. However, their performance varies substantially from place to place depending on climatic conditions, which therefore warrants a tailored design and specification at each geographical location. The current article attempted to investigate the feasibility of extending an existing solar thermal system in a school building in Abu Dhabi to provide dehumidification for the existing air condition system through a desiccant system. The system performance was predicted through a Transient System (TRNSYS) Simulation model to determine the energy savings achieved by the solar-assisted dehumidification system. The current articles determined the effect of fluid flow rate, solar radiation concentration, and heat exchanger effectiveness at the dehumidification of the fresh air as well as energy saved by the proposed system. It was concluded that the system can remove 35% moisture from the air, simultaneously saving 10% of the building's energy. The system cost and benefit analysis revealed a payback period of 7.5 years, considered slightly higher for an attractive investment in such systems. [ABSTRACT FROM AUTHOR]

• CO 2 capture and power to gas technologies were successfully integrated in SNG plant. • Synthetic Natural Gas plant reached near zero lifecycle emissions. • The CO 2 capture caused a slight process efficiency reduction (<1%) • The SNG specific cost was 5.48c$/kWh SNG when CO 2 capture was considered. • Power to Gas plant economic sensitivity analysis was performed. The production of synthetic natural gas from coal and biomass gasification made it possible to obtain a product that can be used to replace easily the standard natural gas in the existing infrastructures. This paper follows and presents a study that was conducted on a synthetic natural gas plant integrated with carbon capture and storage technologies. The recent growth in the use of energy coming from renewable sources requires that balancing measures be taken for electricity grids, which, as can be easily imagined, is best accomplished by using multiple energy storage technologies. In particular, the power-to-gas technology allows renewable electrical energy to be transformed into methane via electrolysis and subsequent methanation. Moreover, the production of synthetic natural gas can be enhanced by using concentrated CO 2 emitted by synthetic natural gas plants, coupling the coal gasification and methanation processes within the same plant. This paper compares and evaluates two distinct process configurations and their implementation with power-to-gas technology in Aspen Plus v.8. During the study, it was analyzed how the introduction of carbon capture and storage technologies affect the overall energy balance, as well as the individual performances of each configuration. The two cases proved to have similar efficiency; it was also observed that the integration of and carbon capture and storage technologies resulted in a negligible reduction in the efficiency of the system (approximately 1%). The integration of power-to-gas technologies led to a decrease in the efficiency of the system up to 30%. Based on the current emission allowances specified in the rules of the regulated market of CO 2, it was also assessed how such technologies would be sustainable in terms of costs derived from the production of gas.. An analysis was in fact performed to estimate the costs associated with this type of plant and the results showed that the introduction of carbon capture and storage technologies in synthetic natural gas plants had a lower impact on the costs related to both the plant and the synthetic natural gas. In this respect, a sensitivity analysis of the most influent factors was performed as well. The results showed that, when it comes to the production of gas in in the power-to-gas process, the specific cost strongly depends on the price of electricity and the operating hours. [ABSTRACT FROM AUTHOR]

Increasing energy demands and oil price volatility have made oil shale attracted more and more attention. However, the shale oil recovery requires huge thermal energy and brings serious environmental problems, such as air pollution. In this paper, to reduce fossil fuel consumption, solar energy, a renewable energy, is introduced. The heat demand and the production yield of the shale oil recovery are obtained through the transients models developed in this paper. Then, three possible energy supply options for the shale oil recovery, i.e. natural gas, the solar thermal energy and the combination of these two, are analyzed and optimized in terms of the net present value and the return on investment over lifetime. The results show that for the shale oil recovery, Option 3, solar energy and gas boiler back up, is the optimal one, which has a return on investment value of 3.12 and can generate $ 72.4 M net present value more return than the Option 1, which uses natural gas only in the project lifetime. • The solar energy is introduced into shale oil recovery to reduce fuel consumption. • Models of key components in shale oil recovery system have been established. • Performances of three energy options are analyzed and optimized. [ABSTRACT FROM AUTHOR]

• Techno-economic analysis of the synthetic route of syngas to aromatics is reported. • Systematic models for direct and indirect route are built based on the Aspen Plus. • Energy consumption and economic aspects are both seriously CO-conversion dependent. • Product selectivity exhibits insignificant effect on the total installation cost and heat utility. • Direct STA route shows advantages at the conversion of CO above 66%–72%, without considering the formation of CO 2. Direct conversion of syngas-to-aromatics (STA) is an increasing vital catalytic field that still contains much uncertainty. For the first time, we report the process simulation of STA via direct routes and indirect STA (syngas first to produce methanol, then methanol being converted into aromatics). The conversion of CO was selected as the sensitivity indicator for the evaluation of energy consumption and economic aspects. A low conversion of CO resulted in a low yield (and low partial pressure) of aromatics and an increasing difficulty in separating them from unreacted syngas and light hydrocarbons. The associated increased investment and operational costs were analyzed quantitatively. Direct STA shows obvious advantages in operational cost savings and in construction costs when the conversion of CO was higher than 66–72% when compared with the indirect STA route. The simulation results provide new insights into the upper limits of the process of developing catalysts. [ABSTRACT FROM AUTHOR]