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Evaluation of the Agricultural Planejamentos for the Subsystem Catolé II and Po o Redondo in the Semi-árido Nordestino
Allan Sarmento Vieira,Valterlin da Silva Santos,Wilson Fadlo Curi
Engenharia Ambiental : Pesquisa e Tecnologia , 2010,
Abstract: To guarantee the reservoirs water use efficiency, because of hydrological uncertainties, has become a great concern for the water resources planning and management in recent years, due to increasing water demands for several uses and environmental degradation, which diminishes the water availability. The objective of this work is to analyze and to compare the performance 2 scenes of agricultural planning for the system of reservoirs Catolé II and Po o Redondo, in the Piancó’s river basin, located in the semiarid region of Paraíba state, through the combination of the optimization and simulation models, both based on sequential linear programming. Each model gets, respectively, from the dry scenario, the performance indicators (reliability, resilience and vulnerability) and the settings for an Optimal Agricultural Planning (POA) of the system, which is compared with the Agricultural Planning proposed by the State Water Resources Policies for the Piancó’s basin river (PAPD). The results showed that PAPD estimated irrigation water demand is not sustainable to attend during years of drought, failing up to 3 consecutive months, in which the attendance was 20% of the required demand. There were no failing events for the fulfillment of POA estimated irrigated water demand due the reduction of 11,5 % of the plantation area.
Minimization of Reservoirs Sedimentation by Optimal Operation of Bottom Outlets  [cached]
E. Valizadegan,M. Shafai Bejestan,H. Mohammad Vali Samani
Journal of Science and Technology of Agriculture and Natural Resources , 2011,
Abstract: Reservoir sedimentation is an unavoidable problem which has unsuitable effects on reservoirs such as decreasing of reservoir useful volume, decreasing of dam stability, unsuitable operation of operational gates and penstocks and decreasing of flood control volume. The minimization of reservoir sedimentation is a nonlinear and constrained optimization problem. Constrains imposed include reservoir storage level and releases in each time, and reservoir storage level in the end of operational period. In this study, after calibration of GSTARS3 software, one of the newest mathematical model for simulation of river and reservoir sedimentation developed by USBR, for region of Voshmgir dam, results of running of software were converted as a part of data file to an optimization model by a mediator computer program. After running the optimization model, results were converted to GSTARS3 by another mediator computer program. Then, GSTARS3 was run again with new data file, obtained from running the optimization model. Results of running of GSTARS3 were converted to the optimization model again. The continuation of this process (loop) finished when the desired accuracy was obtained. In other words, the optimum condition was obtained when the running of this loop finished. The constrained optimization problem changed to unconstrained problem using penalty function method. The Powell method, a method of direct search methods, was used to solve this unconstrained optimization problem. Capabilities of the model were demonstrated through its application to the Voshmgir dam in Gorgan for a 12 month period to obtain the optimal operation policy for minimization of reservoir sedimentation.
Subsystem Code Constructions  [PDF]
Salah A. Aly,Andreas Klappenecker
Mathematics , 2007,
Abstract: Subsystem codes are the most versatile class of quantum error-correcting codes known to date that combine the best features of all known passive and active error-control schemes. The subsystem code is a subspace of the quantum state space that is decomposed into a tensor product of two vector spaces: the subsystem and the co-subsystem. A generic method to derive subsystem codes from existing subsystem codes is given that allows one to trade the dimensions of subsystem and co-subsystem while maintaining or improving the minimum distance. As a consequence, it is shown that all pure MDS subsystem codes are derived from MDS stabilizer codes. The existence of numerous families of MDS subsystem codes is established. Propagation rules are derived that allow one to obtain longer and shorter subsystem codes from given subsystem codes. Furthermore, propagation rules are derived that allow one to construct a new subsystem code by combining two given subsystem codes.
An Improved Artificial Fish Swarm Algorithm for Optimal Operation of Cascade Reservoirs  [cached]
Yong Peng
Journal of Computers , 2011, DOI: 10.4304/jcp.6.4.740-746
Abstract: Based on traditional artificial fish swarm algorithm (AFSA), an improved artificial fish swarm algorithm (IAFSA) is proposed and used to solve the problem of optimal operation of cascade reservoirs. To improve the ability of searching the global and the local extremum, the vision and the step of artificial fish are adjusted dynamicly in IAFSA. Moreover, to increase the convergence speed, the threshold selection strategy is employed to decrease the individual large space gap between before and after update operation in the local update operation. The validity of IAFSA is proved by case study and the threshold parameters of IAFSA are rated.
Propagation Rules of Subsystem Codes  [PDF]
Salah A. Aly
Mathematics , 2008,
Abstract: We demonstrate propagation rules of subsystem code constructions by extending, shortening and combining given subsystem codes. Given an $[[n,k,r,d]]_q$ subsystem code, we drive new subsystem codes with parameters $[[n+1,k,r,\geq d]]_q$, $[[n-1,k+1,r,\geq d-1]]_q$, $[[n,k-1,r+1,d]]_q$. The interested readers shall consult our companion papers for upper and lower bounds on subsystem codes parameters, and introduction, trading dimensions, families, and references on subsystem codes [1][2][3] and references therein.
Subsystem Codes  [PDF]
Salah A. Aly,Andreas Klappenecker,Pradeep Kiran Sarvepalli
Mathematics , 2006,
Abstract: We investigate various aspects of operator quantum error-correcting codes or, as we prefer to call them, subsystem codes. We give various methods to derive subsystem codes from classical codes. We give a proof for the existence of subsystem codes using a counting argument similar to the quantum Gilbert-Varshamov bound. We derive linear programming bounds and other upper bounds. We answer the question whether or not there exist [[n,n-2d+2,r>0,d]]q subsystem codes. Finally, we compare stabilizer and subsystem codes with respect to the required number of syndrome qudits.
Joint Operation of the Multi-Reservoir System of the Three Gorges and the Qingjiang Cascade Reservoirs  [PDF]
Shenglian Guo,Jionghong Chen,Yu Li,Pan Liu,Tianyuan Li
Energies , 2011, DOI: 10.3390/en4071036
Abstract: Optimal utilization of available water resources has become more urgent due to the rapid growth of the economy and population. The joint operation of the Three Gorges cascade and Qingjiang cascade reservoirs in China was studied in this paper. Choosing maximization of hydropower generation and hydropower revenue as objective functions respectively, optimal models were established for individual and joint operation of the cascade reservoirs. The models were solved by the progressive optimality algorithm. The storage and electric compensation benefits among cascade reservoirs were analyzed. The daily inflow data of consecutive hydrological years of 1982–1987 were selected for a case study. Compared with the design operation rule, the joint operation of the multi-reservoir system can generate 5.992 billion kWh of extra power or an increase of 5.70% by the objective function of maximum hydropower generation. Through reservoir storage compensation, the spilled water of the Three Gorges and Qingjiang cascade reservoirs was decreased by 78.741 and 5.384 billion m 3, respectively.
The Optimizing Drawing of Cascade Reservoirs Operation Chart Based on the Routine Operation

杨元园, 黄强, 王义民
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.16066
Abstract: 水库调度图作为指导水电站安全高效运行的依据,一直是水库调度研究的热点,然而现有研究大多以单库调度图为对象进行优化,或是基于中长期发电优化调度模型绘制梯级水库调度图。单库优化调度图较难满足梯级调度要求,而后者虽然理论成熟、应用广泛,但存在建模、求解复杂,步骤繁琐,误差较大等的缺点。鉴此,本文提出了一种采用模拟与优化相结合的技术绘制梯级水库优化调度图的实用方法。该法通过直接优化梯级水库常规调度图的调度线,从而获得优化调度图。以乌江流域4座调节性能较好的水库构成的梯级水库为研究对象进行实例分析,模拟调度结果表明较大地提高了梯级长期发电效益,验证了该法的可靠性和有效性,从而为梯级水库优化调度图的绘制提供了新思路。
Reservoir operation chart has been a hot topic of the reservoir operation study as a basis for the guidance of the efficient and safe operation of the hydropower station. However, existing studies are mostly studying on the optimizing drawing of single reservoir, or research on the drawing of cascade reservoirs operation chart using a long-term power optimization scheduling model. Single reservoir optimized operation chart is hard to meet the cascade scheduling requirements, while the latter theory is mature, widely used, but has its flaws. For this, this paper puts forward a drawing way of cascade reservoirs optimal operation charts, using the combination technology of simulation and optimization, through the direct optimization of the cascade reservoirs conventional operation curves. For the cascade hydropower stations on the WujiangRiver, simulation scheduling results show considerably increase on the cascade long-term generation benefit. Thus verify the reliability and validity of the method, so as to provide a new idea to draw the cascade reservoirs operation chart.
Channel change at Toudaoguai Station and its responses to the operation of upstream reservoirs in the upper Yellow River

RAN Lishan,WANG Suiji,FAN Xiaoli,

地理学报 , 2010,
Abstract: The application of dams built upstream will change the input conditions, including water and sediment, of downstream fluvial system, and destroy previous dynamic quasi-equilibrium reached by channel streamflow, so indispensable adjustments are necessary for downstream channel to adapt to the new water and sediment supply, leading the fluvial system to restore its previous equilibrium or reach a new equilibrium. Using about 50-year-long hydrological, sedimentary and cross-sectional data, temporal response processes of Toudaoguai cross-section located in the upper Yellow River to the operation of reservoirs built upstream are analyzed. The results show that the Toudaoguai cross-section change was influenced strongly by upstream reservoir operation and downstream channel bed armoring thereafter occurred gradually and extended to the reach below Sanhuhekou gauging station. Besides, median diameter of suspended sediment load experienced a three-stage change that is characterized by an increase at first, then a decrease and an increase again finally, which reflects the process of channel bed armoring that began at Qingtongxia reservoir and then gradually developed downstream to the reach below Sanhuhekou cross-section. Since the joint operation strategy of Longyangxia, Liujiaxia and Qingtongxia reservoirs was introduced in 1986, the three-stage change trend has become less evident than that in the time period between 1969 and 1986 when only Qingtongxia and Liujiaxia reservoirs were put into operation alone. In addition, since 1987, the extent of lateral migration and thalweg elevation change at Toudaoguai cross-section has reduced dramatically, cross-sectional profile and location tended to be stable, which is beneficial to the normal living for local people.
Edjackson Marques Ferreira,Andre Gustavo Carvalho Machado,Walter Fernando Araújo Moraes
InternexT : Revista Eletr?nica de Negócios Internacionais da ESPM , 2010,
Abstract: O objetivo deste artigo consiste em analisar as manifesta es dos principais conceitos-chave das teorias de internacionaliza o a partir da trajetória de empresas pertencentes ao setor sucroalcooleiro nordestino. Seis teorias foram selecionadas para nortear a análise empreendida: Ciclo de Vida, Modelo Uppsala, Escolha Adaptativa, o Paradigma Eclético, Vis o Baseada em Recursos e Modelo Diamante. A estratégia de pesquisa adotada foi a de estudo de caso. Os dados foram coletados por meio de documentos do setor e de entrevistas semi-estruturadas. Na etapa de análise dos dados, foi utilizado o software Atlas.ti. Como resultado, evidenciou-se que, nas empresas do setor sucroalcooleiro nordestino, há forte presen a de aspectos relacionados à localiza o e recursos internos, oriundos no Modelo de Diamante, no Paradigma Eclético e no modelo de Vis o Baseada em Recursos. Observa-se, ainda, que a forma o de uma forte rede interna, contemplada pela Teoria de Redes, também se mostrou importante para compreens o de tal fen meno. As demais teorias analisadas tornaram-se menos aplicáveis, principalmente (a) pela natureza típica do setor sucroalcooleiro no estado da Paraíba, centrada em exporta o indireta, e (b) por corresponder a produtos fortemente padronizados.
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