The conditions for transition to a state of supercritical (SC) fluid in the hydrocarbons-water system are examined. A method for thermochemical heating the productive stratum near the oil well ...involving the transition of the oil-water formation fluid to the SC state (homogeneous, inseparable, and extremely fluid) is proposed. New chemical compositions, binary mixtures (BMs) of nitrates of organic amines (organic nitrate) and initiators of their decomposition, capable of ensuring the transition of the fluid to the supercritical state at the expense of high pressures and temperatures generated by rock pressure and heat of the exothermic reaction of BM are tested. The effectiveness of the scheme of production of formation fluid in waterflooded oil fields is assessed.
Three lines of hairy root culture of Ambrosia maritima induced by Agrobacterium rhizogenes ATCC15834 were established. Thiarubrine A, thiarubrine A epoxide, thiarubrine A diol and their precursor ...pentayneene were produced by the hairy roots after elicitation with methyl jasmonate, the common signal molecule in the plant defense and development. Thiarubrine A diol was the main form detected in the medium. Maximum yield was achieved when the 13-day-old hairy root cultures were exposed to 40 mu M methyl jasmonate for 72 h. Callus and cell suspension cultures were established and maintained on Murashige and Skoog medium supplied with alpha -naphthylacetic acid (NAA) and kinetin. When the cell suspension cultures were elicited with methyl jasmonate, pentayneene was the only polyacetylene produced. The yield of pentayneene in hairy root cultures was much higher (9.6 times) than that of cell suspension cultures.
This paper deals with selected areas of concept of Zilina Intelligent Manufacturing System (ZIMS), which is developed by the Faculty of Mechanical Engineering in collaboration with CEIT and other ...faculties of the University of Zilina. Main research areas realized in the framework of ZIMS cover the basic processes in the entire product lifecycle from beginning to end (PLM – Product Lifecycle Management). In this paper two of these areas will be described – manufacturing system design using progressive digital technologies and utilization of automation and robotics in intelligent manufacturing systems.
The effects of salinity, nitrate concentration, pH and temperature on eicosapentaenoic acid (EPA) production by
Porphyridium purpureum were studied. Both systematic and stepwise optimization were ...used in order to determine the best conditions for production of EPA. An analysis method for fatty acids was also developed. The highest EPA production per cell was achieved at pH 7.6 with 41.8 g l
−1 NaCl and 12.1 mM nitrate in the production medium and using a growth temperature of 8°C.
The uncertainty of occurrence of raw coal and coal quality and the various constraints on mine production capacity are the major factors which need to be taken into special consideration in the ...supply chain management (SCM) of coal enterprises. In order to make coal enterprises to quickly respond to changes in customer demand and improve supply chain and logistics management level, this paper presents a supply chain model for coal mine planning with a linear programming model for production scheduling. The goal for the optimization model of production planning and scheduling is to maximize sales volume with the constraints of customer demand, lead time, capacity constraints and inventory in the supply chain. An example of open pit coal mine is used to demonstrate the model application and its ability in reducing planning and scheduling time and responding to uncertainty.
According to the Japanese specialist Taguchi, in order to obtain quality, even the conceptual phase imposes efforts in designing production process parameters, efforts which consist of finding the ...best parameters so that the product should be hyposensitized against disturbances. In other words, the originality of the Taguchi strategy is that it does not aim to eliminate these parasites but to minimize their impact upon quality, eliminating the combination of parameters, which reduces unexpected effects.
This paper describes a project to develop on optimal production plan for crops and livestock in Chang Qing County, People's Republic of China. The production plan was to increase net profit without ...adverse effects on the environment. We set up four large-scale linear programming models, each having more than 3,000 variables and 100 constraints, for different weather conditions and combinations of crops and livestock production. We obtained optimal solutions using computers. We used game theory to work out an optimal plan least sensitive to weather variations. We used sensitivity analysis to obtain the information for production planning as a function of market prices. The project took 1 year; 20 people were involved. More than 3 million data items were used in the development of the models. The optimal production plan involved a 2-year cycle that began in September 1983. By September 1985, the net profit from crops in the county increased by 12.33% and that from livestock by 53.77%. This success opened up the study of production planning and control of the macroscopic economy in agriculture in China. Optimal production plans are being developed and improved in many parts of China.
A multi-period planning model for underground cut-and-fill operations was constructed for the purpose of maximizing discounted profit under given production constraints. The ore grades were estimated ...through geostatistics for minimizing the estimation errors, and production costs were calculated on the basis of the practical operation data. A sequential planning algorithm based on dynamic programming (DP) was then developed to specify the most profitable mining sequence, and applied to a Chinese copper-iron mine employing cut-and-fill stoping. Calculation results showed that the proposed DP-based sequential planning strategy can produce larger discounted profits than those obtained by the advance and retreat mining sequences.
In order to deal with the uncertainties regarding ore grade estimations, production rates and metal prices during overall planning periods, a Chance-constrained programming combined with a dynamic ...programming was developed to incorporate these uncertainties. Four cases of the Chance-constrained programming formulation were proposed under different uncertainty assumptions of ore grades, production rates and metal prices. Simulations were conducted by taking the magnitude of the Chance-constraint and objective function violations into consideration. Simulation results with respect to the studied mine clarify that the increase of the confidence levels of Chance-constraints can lead to the decrease of NPV of the planning project, whereas the increase of the given probabilities of maximizing the allowable limit of the fluctuation of metal prices can lead to the increase of the NPV.
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