Development of manufacturability constraints for press forming of sheet metal components

http://www.worldcat.org/oclc/2869757

Incorporating voltage security into the planning, operation and monitoring of restructured electric energy markets

As open access market principles are applied to power systems, significant changes are happening in their planning, operation and control. In the emerging marketplace, systems are operating under higher loading conditions as markets focus greater attention to operating costs than stability and security margins. Since operating stability is a basic requirement for any power system, there is need for newer tools to ensure stability and security margins being strictly enforced in the competitive marketplace. This dissertation investigates issues associated with incorporating voltage security into the unbundled operating environment of electricity markets. It includes addressing voltage security in the monitoring, operational and planning horizons of restructured power system. This dissertation presents a new decomposition procedure to estimate voltage security usage by transactions. The procedure follows physical law and uses an index that can be monitored knowing the state of the system. The expression derived is based on composite market coordination models that have both PoolCo and OpCo transactions, in a shared stressed transmission grid. Our procedure is able to equitably distinguish the impacts of individual transactions on voltage stability, at load buses, in a simple and fast manner. This dissertation formulates a new voltage stability constrained optimal power flow (VSCOPF) using a simple voltage security index. In modern planning, composite power system reliability analysis that encompasses both adequacy and security issues is being developed. We have illustrated the applicability of our VSCOPF into composite reliability analysis. This dissertation also delves into the various applications of voltage security index. Increasingly, FACT devices are being used in restructured markets to mitigate a variety of operational problems. Their control effects on voltage security would be demonstrated using our VSCOPF procedure. Further, this dissertation investigates the application of steady state voltage stability index to detect potential dynamic voltage collapse. Finally, this dissertation examines developments in representation, standardization, communication and exchange of power system data. Power system data is the key input to all analytical engines for system operation, monitoring and control. Data exchange and dissemination could impact voltage security evaluation and therefore needs to be critically examined

A Toolbox for Tuberculosis Diagnosis: An Indian Multicentric Study (2006-2008): Microbiological Results

BACKGROUND: The aim of this multicentric prospective study in India was to assess the value of several microbiological tools that contribute to the diagnosis of tuberculosis (TB) according to HIV status. METHODS: Standard microbiological tools on individual specimens were analyzed. RESULTS: Among the 807 patients with active TB, 131 were HIV-infected, 316 HIV-uninfected and 360 had HIV-unknown status. Among the 980 non-active TB subjects, 559 were at low risk and 421 were at high risk of M. tuberculosis (Mtb) exposure. Sensitivity of smear microscopy (SM) was significantly lower in HIV-infected (42.2%) than HIV-uninfected (75.9%) (p = 0.0001) and HIV-unknown pulmonary TB patients (61.4%) (p = 0.004). Specificity was 94.5% in non-TB patients and 100% in health care workers (HCW) and healthy family contacts. Automated liquid culture has significantly higher diagnostic performances than solid culture, measured by sensitivity (74.7% vs. 55.9%) (p = 0.0001) and shorter median time to detection (TTD) (12.0 vs. 34.0 days) (p = 0.0001). Specificity was 100% in HCW and cured-TB patients, but was lower in non-TB patients (89%) due to isolation of Mycobacteria other than tuberculosis (MOTT). TTD by both methods was related to AFB score. Contamination rate was low (1.4%). AccuProbe hybridization technique detected Mtb in almost all culture-positive specimens, but MOTT were found in 4.7% with a significantly higher frequency in HIV-infected (15%) than HIV-uninfected TB patients (0.5%) (p = 0.0007). Pre-test classification significantly increased the diagnostic value of all microbiological tests in pulmonary TB patients (p<0.0001) but to a lesser degree in extrapulmonary TB patients. CONCLUSIONS: Conventional microbiological tools led to results similar to those already described in India special features for HIV-infected TB patients included lower detection by SM and culture. New microbiological assays, such as the automated liquid culture system, showed increased accuracy and speed of detection

Distributor pricing approaches enabled in Smart Grid to differentiate delivery service quality

Industry practitioners who advocate retail competition and Demand-side Participation now look for approaches to link both initiatives through distributor pricing. As distributors incrementally convert more traditional assets into Smart Grid assets, they also need to consider different pricing approaches to recover the investment costs and meet the regulatory business requirements. Small electricity consumers need incentives to take part in these initiatives but their delivery service quality should also be closely guarded. Hence this paper addresses the above needs as a whole and investigates a set of distributor pricing approaches with Smart Grid technologies. Pricing of network and non-network based solutions should follow the incremental basis, such as the long run average incremental cost (LRAIC). The benefit of deferring network investment is calculated and should be passed to consumers as peak pricing rebate. A concept of reliability premium (RP) based on load point reliability index is proposed, through which customers can express their preference of service quality and adjust their network tariff payment accordingly. A service delivery model is also proposed to utilize the savings from wholesale market trading to compensate for the downgraded service when loads are controlled. The IEEE 123-node distribution test feeder and the IEEE distribution system for RBTS Bus No. 2 are simulated, and solved using General Algebraic Modeling System (GAMS) to demonstrate the proposed distributor pricing approaches in Smart Grid

Differential response of silkworm, Bombyx mori L. to phytoecdysteroid depending on the time of administration

The differential response of silkworm, Bombyx mori   L. to phytoecdysteroid when administered at different ages of 5th instar was studied on a popular Chinese silkworm hybrid, Xinhang x Keming reared on the 'Hu Sang 197' variety of mulberry leaves. Phytoecdysteroid, a chlolest -7 ene- 6- one- carbon skeleton (C27) from a plant source, Radyx achyranthes   was administered to 5th instar silkworm per os at a rate of 2 μm per larva to different batches of silkworm at 48 h, 72 h and at the onset of cocoon spinning when a few larvae were ripe. The larval duration, larval mounting duration, cocoon characters and reeling traits were influenced by phytoecdysteroid. The intensity of influence was dependent on the time of application. The larvae treated at 48 h improved almost all economic traits significantly with a marginal increase in larval duration. In the larvae treated at 72 h, the economic traits were adversely affected but the larval duration was shortened by about 24 hours. In the larvae treated at the onset of cocoon spinning, the mounting duration was substantially reduced without much affect on the cocoon traits which would be a big benefit in commercial sericulture. The physiological significance of varied response of silkworm to phytoecdysteroid administration is discussed. @JASE

Voltage stability constrained load curtailment procedure to evaluate power system reliability measures

Abstract--This paper reports a method to evaluate composite power system reliability indices incorporating the voltage stability margin criteria. To compute the load curtailment evaluation, an optimal power flow (OPF) computation algorithm, considering the steady state voltage stability margin constraint is developed. A steady state voltage stability indicator is first discussed for its applicability as a suitable indicator for representing stability margin from the collapse point. The load curtailment formulation is then evolved and described into the OPF’s objective function. A criterion based on the voltage stability indicator is then incorporated as an additional constraint into the OPF. A numerical example has been used to illustrate the effect of the algorithm on the composite system reliability evaluation. The Expected Energy Not Served (EENS) and down time is computed, both analytically and by the Monte Carlo Simulation

Incorporating TCSC into the Voltage Stability Constrained OPF Formulation

Abstract--This paper investigates the effect of Thyristor Controlled Series Capacitor (TCSC) on the voltage stability constrained Optimal Power Flow (OPF) formulation where the objective function is to minimize power system load curtailment. Incorporating TCSC affects the topology and hence the power flow distribution. Some numerical cases are presented to discuss the effects of TCSC that is expected when it is incorporated into the load curtailment formulation. The test result reflects the impacts TCSC has in reducing load curtailment during a line congestion situation. The paper also discusses the applicability of the approach in security based reliability studies for systems having control components lik