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The energy crisis and environmental concerns have accelerated the development of the active distribution network (ADN) with a high proportion of renewable energy, which poses a challenge to the operation of the power system. Moreover, using active management means to promote the consumption of renewable energy is an important task of ADN. Therefore, as an important operation means, the network reconfiguration is used to enhance the adjustable capacity of the power system at the planning stage. Firstly, a “wind–light–load” uncertain scenario set is constructed to address the uncertainty of wind speed, lighting, and load. On this basis, a robust optimization model for distributed power generation taking into account network reconstruction and in ADN is proposed. In addition, the distributed generator (DG) permeability indicator is introduced in the planning model to improve the ADN ability of absorbing renewable energy. A linearized AC power flow model is utilized to calculate the power flow. Finally, via simulation in an IEEE 33-bus system and IEEE 69-bus system, the influence of network reconfiguration and robustness on distributed generator planning, economy and reliability of ADN is analyzed, and the validity of the model is verified.

To develop the Chinese version of Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) and examine its psychometric properties, we investigated a sample of 689 non-clinical and 309 cli...

The dependence of the low-frequency hysteresis of Pb[Zr0.52Ti0.48]O3 ceramics upon coupled thermomechanical effect was experimentally examined based on the framework of power-law scaling. A new scaling relation was found to account for the observed hysteresis behavior under controlled temperature and mechanical compression while the strength and frequency of the electric field were kept constant. In the newly developed scaling relation, additional power functions of the stress are introduced and coupled with the electrical and thermal terms to describe the observed coupling effect. As a result, the difference in the hysteresis area between the stress-free state and the stressed state depends not only on the electromechanical coupling, but also on a newly introduced thermomechanical coupling term. This new scaling relation was confirmed by the experimental observations.

In the production of stator cores, it is relied upon experienced engineers to make time sensitive decisions on the number of compensation sheets to be added to achieve uniform pressure distribution though out the laminations. However, this method yields inconsistent results as humans are unable to store and analyze large amounts of data. In this paper ANNs have been employed to help the engineers with the decision making process. The ANNs are trained using a hybrid Genetic Algorithm (GA) – Levenberg-Marquardt (LM) to avoid local convergence. When used on testing data sets, the ANNs displayed a high degree of prediction accuracy indicating their ability to simulate the decision making process of these experienced engineers.

Wind resources are considered to be one of the most promising alternative energy sources. It is difficult to achieve the maximum utilization of wind energy by artificial maintenance scheduling, because of poor operating environment, poor site accessibility, and other objective factors such as randomness. According to health of turbines, wind power forecasting results, maintenance resource availability, weather and other factors, how to achieve the minimum maintenance cost and minimum wind power loss of offshore wind farms in the short-term maintenance task optimization scheduling is still a difficult problem facing the industry. This paper presented an optimization model for the scheduling of short term maintenance scheduling in offshore wind field, the optimization model belongs to nonlinear optimization problem with constraints, and uses the Gurobi to solve the optimization problem with the minimum wind field maintenance cost and the minimum wind power loss.

The blend composite materials of bio-ethanol byproduct-Poly(lactic acid) (PLA) were produced by a twin-screw extrusion process. Effects of bio-ethanol byproduct (BEB) contents and different compatibilizers on properties of composite materials were investigated. The research showed that with the increase of contents of bio-ethanol byproduct, the mechanical properties decreased. The mechanical properties of composites were improved by adding the compatibilizers, especially the polypropylene grafted maleic anhydride (PP-MAH). When the PP-MAH content was 2.5%, the mechanical properties of the composite materials were superior to others.

Background: Psoriasis is a cutaneous disorder of multifactorial etiology influenced by both genetic and environmental factors such as infection. Methods: We conducted a genome analysis with 20 microsatellite markers spanning the long arm of chromosome 1 in 36 Chinese families with psoriasis and detected evidence for linkage at 1q21 with a nonparametric linkage score of 1.74, p = 0.03, and 1q32 with one of 1.84, p = 0.03. According to the positional and functional candidate principle, we further investigated the single-nucleotide polymorphisms of the HAX-1 gene (located in 1q21) and IL-20 gene (located in 1q32) in a case-control study including 340 sporadic patients and 199 controls. Results: We determined that the frequency of the G allele of IL-20 –1723C→G (rs1713239) was significantly higher among psoriatic patients (38.5% in cases vs. 31.2% in controls, p = 0.015, odds ratio, OR = 1.39, 95% confidence interval, CI = 1.07–1.80). When we stratified our analysis by psoriasis triggered or exacerbated by infection of the upper respiratory tract, a significant difference was detected (42.4% in stratified cases vs. 31.2% in controls, p = 0.005, OR = 1.63, 95% CI = 1.15–2.30). Conclusion: We assume that triggered or exacerbated by respiratory tract infection, the population with the G allele of IL-20 –1723C→G are predisposed to psoriasis.

In this work the coupled electromechanical behaviors of the overall properties of ferroelectric ceramics have been experimentally studied with different initial poling states and loading frequencies in order to have a better understanding of their domain switching mechanism. The material under investigation is soft PZT-5 ceramic, which shows noticeable nonlinear response upon externally applied load. The experimental results show that the state of initial poling in the specimens can evidently affect the characteristics of the hysteresis loops. The electrical loading frequency dependence of the ferroelectric properties of PZT-5, e.g., coercive field, remnant polarization, etc., has also been investigated through the tests conducted on the carefully designed multi-field testing system. Despite some common features of frequency dependence shared by all three types of initial poling, it is found out that the effects of loading frequency on the change of coercive field and remnant polarization for the specimen poled perpendicular to the switching axis deviate from those of the other two poling states, and this may be attributed to the specific domain switching mechanism for the perpendicularly poled specimen.Copyright © 2012 by ASME