The effect of water containing sodium sulfate ions on strength of concrete of aquaculture ponds and channels

Aquaculture is among the oldest occupations of human being. Over the past quarter of century, the aquaculture industry has grown rapidly. The effect of water containing sodium sulfate on long term compressive strength of concrete of fishing ponds and channels is investigated in this paper. Aim of this paper was to analyze the strength of concrete channels and of aquaculture which are in direct contact with dissolved sodium sulfate. This is an ongoing laboratory investigation which consisted of 480 standard casting concrete cube mix designs and subjecting them to different curing condition environments. Analyzing laboratory results, it was found that for short period of time, the effect was negligible, but for longer periods up to seven months, EC (electrical conductivity) of water had a low negative effect on compressive strength of concrete, while specimens were placed in waters with different ECs. On the other hand, average compressive strength of concrete was almost 25 kg/cm^2 lower than estimated. However, loading the sample concretes up to failure resulted in strength loss of up to 10%. To solve this problem, designed compressive strength must be considered 10% higher than actual in order to have an acceptable concrete strength for water channels and ponds which are in direct contact with sodium sulfate ions in the water

Implementation of Value Engineering for strategy formulation (Case study: Fisheries sector)

This paper analyzes the results of implementing Value Engineering (VE) into SWOT methodology undertaken in Yazd province of Iran. This is the first time that these techniques have been undertaken for fisheries sector in Iran. The study mainly aims at applying Value Engineering and SWOT techniques to achieve the best out of decision-making, and also of management issues as a whole, through the consideration of creative ideas for improvement. The analyses use scientific trawl data and standardized analysis techniques. Based upon the analysis of fisheries issues, findings indicate that the optimized policy is to introduce new sea food chain restaurants into the studied province. Moreover, other suggestions could be as follows: advertising and good standard packaging for export, building facilities for processing and refrigeration by investors, producing Salmon for export in good packaging, producing crabs and other new species, encouraging people to consume more fish, paying great attention to research works, government supporting for transportation, loan, and subsidies, and finally encouraging investors

An exact Method for Stochastic Maximal Covering Problem of Preventive Healthcare Facilities

Abstract Effective preventive healthcare services have a significant role in reducing fatality and medical expenses in all human societies and the level of accessibility of customers to these services can be considered as a measure of their efficiency and effectiveness. The main purpose of this paper is to develop a service network design model of preventive healthcare facilities with the principal objective of maximizing participation in the offered services. While considering utility constraints and incorporating demand elasticity of customers due to travel distance and congestion delays, optimal number, locations and capacities of facilities as well as customer assignment o facilities are determined. First, the primary nonlinear integer program is transformed, and then the linearized model is solved by developing an exact algorithm. Computational results show that large-sized instances can be solved in a reasonable amount of time. An illustrative case study of network of hospitals in Shiraz, Iran, is used to demonstrate the model and the managerial insights are discussed

Development of a novel lot sizing model with variable lead time in supply chain environment

Supply chain management (SCM) addresses the management of materials and information across the entire chain from suppliers to producers, distributors, retailers, and customer. The theory of supply chain management suggests that lead time reduction is a pioneer to the use of market mediation to reduce transaction uncertainty in the chain, which can be conceptualized as the primary goal of supply chain management. In the past few decades, scholars gave ample attention about the impact of inventory on SCM. This paper relates to the development of a lot sizing model for a single component multiple delivery system with variable demand and lead time of a multinational transformer company. Two models and the modification were developed on the basis of the following assumptions. For first model distribution of demand is normal, distribution of procurement lead time is exponential and the quantity is coming in a single lot. For second model distribution of demand is normal distribution of ‘procurement’ and ‘administrative delay’ lead time is exponential and the quantity is coming in a single lot. Modification of the first model has been done by taking the effect of multiple deliveries in the models and correcting the Re-order point as obtained from the previous models. The results were observed by the second model and analysis has been done for different parametric conditions. The effect of multiple deliveries is also taken into account. The optimum re-order point and economic ordering quantity with various different inputs have been discussed

High Precision In-Situ Raman Spectroscopy on a Novel Room-Temperature Superconductor, Carbonaceous Sulfur Hydride, Under Pressure and Cryogenic Temperatures

Superconductivity is an incredible quantum phenomenon that historically only occurred at low temperatures. Recently, room-temperature superconductivity was discovered and will have various benefits and advantages in application, such as revolutionizing the energy grid, making medical imaging more accessible, and solving problems in related sciences. We have experimentally investigated carbonaceous sulfur hydride (CSH), a novel room-temperature superconductor, at varying cryogenic temperatures and pressures through high precision Raman spectroscopy. The current understanding of the material lacks information about the chemical structure and stoichiometry. Investigating the temperature and pressure space of its Raman spectra will give insight on important details about its structure, chemical composition, and phase diagram while other investigative methods are not suitable. CSH was synthesized in a diamond anvil cell (DAC) and taken to 12 GPa at ambient temperature. Raman scattering data for CSH’s vibrational spectra was collected on warm up from 10K to 293K at a pressure of 28 GPa. Various thermal broadenings, a temperature induced phase transition in the lattice mode region of the spectra, and present C-H modes at low temperatures are observed.https://digitalscholarship.unlv.edu/durep_podium/1028/thumbnail.jp

Implementing Bounded Linear Programming and Analytical Network Process Fuzzy Models to Motivate Employees: a Case Study

In this research, the factors affectinguniversity employees’ motivation and productivity are identified and classified in seven groups; the impact of each motivation factor on the productivity is presented by ANP fuzzy model.Eight universities in Iran were analyzed in this research work. The aim of this study is to explore the productivity of employees. This paper attempts to give new insights intodesigning the portfolio factors, motivating employees for productivity improvement by implementing BLP and ANP fuzzy models.The research results show that there is a positive and significant relationship among reward system, motivation factors, and human resources productivity. In addition, among the options of reward system, the factors of internal (inherent) reward, non-financial external reward, and financial external reward had the highestimpact on increasing motivation and productivity factors. At the next stage, a BLP model is designed according to the importance and impact of each reward system option on motivation and productivity factors and organization limitations, including budget, facilities, and conditions to design portfolio factors motivating employees with the aim of improving productivity. The research results show that actualizing performance evaluation, receiving the feedback from the results of doing tasks by different ways, providing an opportunity for all employees to progress, coordination between job specifications and employees’ abilities, and a manager competency are very critical for improving the organization productivity

Multiple Regression Analysis in the Development of NiFe Cells as Energy Storage Solutions for Intermittent Power Sources Such as Wind or Solar

Multiple regression analysis was used to investigate the effect of bismuth sulphide and iron sulphide as anode additives for NiFe cells. With this in mind, in-house made Fe/FeS/Bi2S3 based electrodes were cycled against commercially available nickel electrodes. A simplex centroid design was used to investigate the combined effects of any of the aforementioned additives on cell performance. The manuscript ends with an initial look at electrolyte systems as a means to further improve the performance of our cells. Finally, our findings support the idea that HS- ions improve the overall performance of NiFe cells