941 resultados para average current control


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Dissertação (mestrado)—Universidade de Brasília, Faculdade UnB Planaltina, Mestrado em Ciências de Materias, 2016.

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This study tested the hypothesis that career indecisiveness among men tends to be associated with different levels of self-reported psychological adjustment and with different remembrances of parental (maternal and paternal) acceptance and behavioral control in childhood from those of women. One hundred twenty-six respondents ages 17 through 54 (M = 23.7 years, SD = 8.21 years) participated in this study. Thirty-seven where males; 90 were females. Measures used in this study included the Career Decision Scale, the Adult version of the Parental Acceptance-Rejection/Control Questionnaire for mothers and for fathers, and the Adult version of the Personality Assessment Questionnaire. Both men and women remembered their mothers as well as their fathers as being loving in childhood. Additionally, men and women remembered both parents as being moderately behaviorally controlling in childhood. Finally, both men and women reported a fair level of psychological maladjustment. And on average, both men and women were fairly indecisive about their careers. Results of analyses supported the hypothesis in that career indecisiveness among women but not men was significantly correlated with remembered maternal and paternal acceptance in childhood, as well as with self-reported psychological adjustment and age. However, only women’s self-reported psychological adjustment made a significant and unique contribution to variations in their reports of career indecisiveness. None of the predictor variables were significantly associated with career indecisiveness among men.

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The procedure of on-line process control by attributes, known as Taguchi`s on-line process control, consists of inspecting the mth item (a single item) at every m produced items and deciding, at each inspection, whether the fraction of conforming items was reduced or not. If the inspected item is nonconforming, the production is stopped for adjustment. As the inspection system can be subject to diagnosis errors, one develops a probabilistic model that classifies repeatedly the examined item until a conforming or b non-conforming classification is observed. The first event that occurs (a conforming classifications or b non-conforming classifications) determines the final classification of the examined item. Proprieties of an ergodic Markov chain were used to get the expression of average cost of the system of control, which can be optimized by three parameters: the sampling interval of the inspections (m); the number of repeated conforming classifications (a); and the number of repeated non-conforming classifications (b). The optimum design is compared with two alternative approaches: the first one consists of a simple preventive policy. The production system is adjusted at every n produced items (no inspection is performed). The second classifies the examined item repeatedly r (fixed) times and considers it conforming if most classification results are conforming. Results indicate that the current proposal performs better than the procedure that fixes the number of repeated classifications and classifies the examined item as conforming if most classifications were conforming. On the other hand, the preventive policy can be averagely the most economical alternative rather than those ones that require inspection depending on the degree of errors and costs. A numerical example illustrates the proposed procedure. (C) 2009 Elsevier B. V. All rights reserved.

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Objective To assist with strategic planning for the eradication,of malaria in Henan Province, China, which reached the consolidation phase of malaria control in 1992, when only 318 malaria cases were reported, Methods We conducted a prospective two-year study of the costs for Henan's malaria control programme. We used a cost model that could also be applied to other malaria programmes in-mainland China, and analysed the cost of the three components of Henan's malaria programme. suspected malaria case management,, vector surveillance,,and population blood surveys. Primary cost data were collected from the government, and data on suspected malaria patient's were collected in two malaria counties (population 2 093 100). We enlisted the help of 260 village doctors. in six-townships or former communities (population 247 762), and studied all 12 315 reported cases of suspected malaria in catchment areas in 1994 and 1995. Findings The average-annual government investment in malaria control was estimated to be US$ 111 516 (case-management 59%; active blood surveys 25%;vector surveillance 12%; and contingencies and special projects 4%). The average cost (direct and indirect) for-patients seeking-treatment for suspected malaria was US$ 3.48, equivalent,to 10 days' income for rural residents. Each suspected malaria case cost the government an, average of US$ 0.78. Conclusion Further cuts in government funding will increase future costs, when epidemic malaria returns; investment in malaria control should therefore continue at least at current levels,of US$ 0.03 per person a risk.

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Several didactic modules for an electric machinery laboratory are presented. The modules are dedicated for DC machinery control and get their characteristic curves. The didactic modules have a front panel with power and signal connectors and can be configurable for any DC motor type. The three-phase bridge inverter proposed is one of the most popular topologies and is commercially available in power package modules. The control techniques and power drives were designed to satisfy static and dynamic performance of DC machines. Each power section is internally self-protected against misconnections and short-circuits. Isolated output signals of current and voltage measurements are also provided, adding versatility for use either in didactic or research applications. The implementation of such modules allowed experimental confirmation of the expected performance.

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Multilevel power converters have been introduced as the solution for high-power high-voltage switching applications where they have well-known advantages. Recently, full back-to-back connected multilevel neutral point diode clamped converters (NPC converter) have been used inhigh-voltage direct current (HVDC) transmission systems. Bipolar-connected back-to-back NPC converters have advantages in long-distance HVDCtransmission systems over the full back-to-back connection, but greater difficulty to balance the dc capacitor voltage divider on both sending and receiving end NPC converters. This study shows that power flow control and dc capacitor voltage balancing are feasible using fast optimum-predictive-based controllers in HVDC systems using bipolar back-to-back-connected five-level NPC multilevel converters. For both converter sides, the control strategytakes in account active and reactive power, which establishes ac grid currents in both ends, and guarantees the balancing of dc bus capacitor voltages inboth NPC converters. Additionally, the semiconductor switching frequency is minimised to reduce switching losses. The performance and robustness of the new fast predictive control strategy, and its capability to solve the DC capacitor voltage balancing problem of bipolar-connected back-to-back NPCconverters are evaluated.

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Solar photovoltaic systems are an increasing option for electricity production, since they produce electrical energy from a clean renewable energy resource, and over the years, as a result of the research, their efficiency has been increasing. For the interface between the dc photovoltaic solar array and the ac electrical grid is necessary the use of an inverter (dc-ac converter), which should be optimized to extract the maximum power from the photovoltaic solar array. In this paper is presented a solution based on a current-source inverter (CSI) using continuous control set model predictive control (CCS-MPC). All the power circuits and respective control systems are described in detail along the paper and were tested and validated performing computer simulations. The paper shows the simulation results and are drawn several conclusions.

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Schistosomiasis control was impossible without effective tools. Synthetic molluscicides developed in the 1950s spearheaded community level control. Snail eradication proved impossible but repeated mollusciciding to manage natural snail populations could eliminate transmission. Escalating costs, logistical complexity, its labour-intensive nature and possible environmental effects caused some concern. The arrival of safe, effective, single-dose drugs in the 1970s offered an apparently better alternative but experience revealed the need for repeated treatments to minimise reinfection in programmes relying on drugs alone. Combining treatment with mollusciciding was more successful, but broke down if mollusciciding was withdrawn to save money. The provision of sanitation and safe water to prevent transmission is too expensive in poor rural areas where schistosomiasis is endemic; rendering ineffective public health education linked to primary health care. In the tropics, moreover, children (the key group in maintaining transmission) will always play in water. Large scale destruction of natural snail habitats remains impossibly expensive (although proper design could render many new man-made habitats unsuitable for snails). Neither biological control agents nor plant molluscicides have proved satisfactory alternatives to synthetic molluscicides. Biologists can develop effective strategies for using synthetic molluscicides in different epidemiological situations if only, like drugs, their price can be reduced.

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Sustainability has become a focal point of the international agenda. At the heart of its range of distribution in the Gran Chaco Region, the elimination of Triatoma infestans has failed, even in areas subject to intensive professional vector control efforts. Chagas disease control programs traditionally have been composed of two divorced entities: a vector control program in charge of routine field operations (bug detection and insecticide spraying) and a disease control program in charge of screening blood donors, diagnosis, etiologic treatment and providing medical care to chronic patients. The challenge of sustainable suppression of bug infestation and Trypanosoma cruzi transmission can be met through integrated disease management, in which vector control is combined with active case detection and treatment to increase impact, cost-effectiveness and public acceptance in resource-limited settings. Multi-stakeholder involvement may add sustainability and resilience to the surveillance system. Chagas vector control and disease management must remain a regional effort within the frame of sustainable development rather than being viewed exclusively as a matter of health pertinent to the health sector. Sustained and continuous coordination between governments, agencies, control programs, academia and the affected communities is critical.

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Combined audit report on the institutions under the control of the Iowa Department of Human Services including findings and recommendations and average cost per resident/patient information for the five years ended June 30, 2006

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The multiscale finite-volume (MSFV) method is designed to reduce the computational cost of elliptic and parabolic problems with highly heterogeneous anisotropic coefficients. The reduction is achieved by splitting the original global problem into a set of local problems (with approximate local boundary conditions) coupled by a coarse global problem. It has been shown recently that the numerical errors in MSFV results can be reduced systematically with an iterative procedure that provides a conservative velocity field after any iteration step. The iterative MSFV (i-MSFV) method can be obtained with an improved (smoothed) multiscale solution to enhance the localization conditions, with a Krylov subspace method [e.g., the generalized-minimal-residual (GMRES) algorithm] preconditioned by the MSFV system, or with a combination of both. In a multiphase-flow system, a balance between accuracy and computational efficiency should be achieved by finding a minimum number of i-MSFV iterations (on pressure), which is necessary to achieve the desired accuracy in the saturation solution. In this work, we extend the i-MSFV method to sequential implicit simulation of time-dependent problems. To control the error of the coupled saturation/pressure system, we analyze the transport error caused by an approximate velocity field. We then propose an error-control strategy on the basis of the residual of the pressure equation. At the beginning of simulation, the pressure solution is iterated until a specified accuracy is achieved. To minimize the number of iterations in a multiphase-flow problem, the solution at the previous timestep is used to improve the localization assumption at the current timestep. Additional iterations are used only when the residual becomes larger than a specified threshold value. Numerical results show that only a few iterations on average are necessary to improve the MSFV results significantly, even for very challenging problems. Therefore, the proposed adaptive strategy yields efficient and accurate simulation of multiphase flow in heterogeneous porous media.

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The routine maintenance along Iowa's highways and roadways during the summer growing season is a time consuming and costly endeavor. Trimming around guardrail posts and delineator posts is especially costly due to the handwork required. Trimming costs account for approximately 50% of the shoulder mowing costs according to expense figures obtained from the Iowa Department of Transportation (DOT), Office of Maintenance. The FY 2001 statewide trimming costs for the Iowa DOT was approximately $430,000 ($305,000 labor, $125,000 equipment and materials). This product would be required to perform well for 9-21 years, on average, in order to recoup the cost of installation. This includes the durability of the product, but not the cost of repair due to traffic damage, snowplow and wing damage, or damage caused by mowing operations. Maintenance costs associated with vegetation creep over the mats and repair costs would extend the required service life. As a result of resource realignment, the Iowa DOT roadside maintenance policy, for FY 2003 and the future, will be to eliminate trimming around delineator posts unless the reflector is obstructed. This policy change will effectively eliminate the need for weed control mats due to the significant reduction in trimming. The use of the weed control mats could be justified in areas that are dangerous to maintenance workers such as guardrail installations in high traffic areas. Because the delineator posts are further from the edge of the traveled roadway, there is a reduced risk to the maintenance workforce while hand trimming. Because the DuroTrim Vegetation Control Mats appear to have performed adequately in the field trial, they could be considered for use, where safety conditions warrant. That use should be limited, however, due to the considerable initial cost and changes in Iowa DOT roadside maintenance policy. Application should be limited to instances where the use of the DuroTrim Vegetation Control Mats would have a significant impact on the safety of the roadside maintenance workers. The cost savings, due to the elimination of the trimming and mowing alone, is not enough to justify their use in most situations at their current cost. The test sections will continue to be monitored periodically so that approximate service life can be determined.

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[Summary] 2. Roles of quality control in the pharmaceutical and biopharmaceutical industries. - 2.1. Pharmaceutical industry. - 2.2. Biopharmaceutical industry. - 2.3. Policy and regulatory. - 2.3.1. The US Food and Drug Administration (FDA). - 2.3.2. The European Medicine Agency (EMEA). - 2.3.3. The Japanese Ministry of Work, Labor and Welfare (MHLW). - 2.3.4. The Swiss Agency for Therapeutic Products (Swissmedic). - 2.3.5. The International Conference on Harmonization (ICH). - - 3. Types of testing. - 3.1. Microbiological purity tests. - 3.2. Physiochemical tests. - 3.3. Critical to quality steps. - 3.3.1. API starting materials and excipients. - 3.3.2. Intermediates. - 3.3.3. APIs (drug substances) and final drug product. - 3.3.4. Primary and secondary packaging materials fro drug products. - - 4. Manufacturing cost and quality control. - 4.1.1. Pharmaceutical manufacturing cost breakdown. - 4.1.2. Biopharmaceutical manufacturing cost breakdown. - 4.2. Batch failure / rejection / rework / recalls. - - 5. Future trends in the quality control of pharmaceuticals and biopharmaceuticals. - 5.1. Rapid and real time testing. - 5.1.1. Physio-chemicals testing. - 5.1.2. Rapid microbiology methods