Planning, operation, and design of market-based virtual power plant considering uncertainty

The power systems of today seem inseparable from clean energy sources such as wind turbines (WTs) and photovoltaics (PVs). However, due to their uncertain nature, operational challenges are expected when WT and PV energy is added to the electricity network. It is necessary to introduce new technologies to compensate for the intermittent nature of renewable energy sources (RESs). Therefore, rationally implementing a demand response (DR) program with energy storage systems (ESSs) in a virtual power plant (VPP) environment is recommended as a way forward to minimize the volatile nature of RESs and improve power system reliability. Our proposed approach aims to maximize social welfare (SW) (i.e., maximization of consumer benefits while minimizing energy costs). Our method assesses the impact of the DR program on SW maximization. Two scenarios are examined, one with and one without a DR program. Stochastic programming theory is used to address the optimization problem. The uncertain behavior of WTs, PVs, and load demand is modeled using a scenario-based approach. The correctness of the proposed approach is demonstrated on a 16-bus UK generic distribution system. Our results show that SW and active power dispatch capacity of WT, PV, and ESS are fairly increased using the proposed approach. View Full-Tex

A review on hyperthermia via nanoparticle-mediated therapy

Hyperthermia treatment, generated by magnetic nanoparticles (MNPs) is promising since it is tumour-focused, minimally invasive and uniform. The most unique feature of magnetic nanoparticles is their reaction to and manipulation by a magnetic force which is responsible for enabling their potential as heating mediators for cancer therapy. With magnetic nanoparticle hyperthermia, a tumour is preferentially loaded with systemically administered nanoparticles with high-absorption cross section for transduction of an extrinsic energy source to heat. To maximize the energy deposited in the tumour while limiting the exposure in healthy tissues, the heating is achieved by exposing the region of tissue containing magnetic nanoparticles to an alternating magnetic field. The magnetic nanoparticles dissipate heat from relaxation losses thereby heating localized tissue above normal physiological ranges. Besides thermal efficiency, the biocompatibility of magnetite nanoparticles assists in their deployment as efficient drug carriers for targeted therapeutic regimes. In the present article we provide a state-of-the-art review focused on progress in nanoparticle induced hyperthermia treatments which have several potential advantages over both global and local hyperthermia treatments achieved without nanoparticles. Green bio-nanotechnology has attracted substantial attention and has demonstrable abilities to improve cancer therapy. Furthermore we have listed the challenges associated with this treatment along with future opportunities in this field which it is envisaged will be of interest to biomedical engineers, bio-materials scientists, medical researchers and pharmacological research groups

Reformation of corporate governance in Malaysia : do changes in audit and accountability practices increase institutional performance?

Following a sequence of financial crises around the world, a series of corporate governance codes were issued concerning best practice with regard to corporate governance reformation. Central to these codes was the aim of the government to create investor confidence, to raise the standard, drive corporate governance reforms and use as a benchmark monitoring and implementing as corporate governance practices and policies at the corporate company level. The Malaysian government is committed to ensure that corporate companies demonstrate a track record of good governance in order to attract and retain long-term investors. Therefore, after seven years, the first Malaysian Code on Corporate governance (MCCG) was introduced in 2000, while the revised MCCG was introduced in 2007. The amendments of MCCG 2000 involved the components of audit committees and board of directors. It was aimed to improve the quality of audit committees and board of director’s functions among Publicly Listed Companies (PLCs) in promoting accountability and high levels of protection for the investor. This article aims to examine the effect of the Malaysian Code on Corporate governance on audit and accountability practices by comparing practices prior to, and after the implementation of the Code. Furthermore, the relationship between changes in audit and accountability practices and institutional performance in terms of corporate governance reformation is also examined

2-Azido-1-(4-methyl­phen­yl)ethanone

In the mol­ecule of the title compound, C9H9N3O, the angle formed by the least-squares line through the azide group with the normal to the plane of the benzene plane ring is 46.62 (16)°. The crystal structure features C—H⋯O hydrogen bonds, which link the mol­ecules into zigzag chains running parallel to [010]

The response of sugarcane (Saccharum officinarum L) genotypes to callus induction, regeneration and different concentrations of the selective agent (geneticin -418)

Two commercial cultivars (CPF-245 and CPF-237) and three advanced lines (CSSG-668, S-2003US633, S-2003US114) of sugarcane (Saccharum officinarium) grown in Punjab, Pakistan were evaluated for their potential to induce callus, embryogenic callus and regeneration. Cultivar CSSG-668 was found to be the best genotype yielding maximum embryogenic callus and regeneration whereas cultivar CPF- 245 exhibited lowest callus induction frequency. Five different concentrations (0, 20, 40, 60, and 80mg/L) of the selective agent (geneticin-418) were used to optimize selection conditions with nontransformed embryogenic calli. The geneticin concentration 60 mg/L was found to be the optimal dose to select the embryogenic calli of genotypes CSSG-668, CPF-245 and S-2003US63, while 35 mg/L geneticin was found to be the best concentration for S-2003US-114. Similarly, 60 mg/L geneticin was optimum dose to select regenerated plantlets of the cultivars CSSG-668 and CPF-245 while it was 40, 25 mg/L for the cultivars S-2003US-114 and S-2003US-633, respectively. It is concluded from the present study that geneticin concentration in the range of 25 to 60 mg/L can be effectively used for the selection of transformed embryogenic calli and regenerants of different sugarcane cultivars.Keywords: Callus induction, embryogenic callus, regeneration, Saccharum officinarum L., selection, geneticin

2-Azido-1-(4-nitro­phen­yl)ethanone

In the title compound, C8H6N4O3, the ketone [C—C(=O)—C] and nitro groups are tilted with respect to the benzene ring by 18.92 (6) and 24.11 (15)°, respectively. In the crystal, mol­ecules are linked into inter­woven chains running parallel to the [100] direction by C—H⋯N hydrogen bonds and weak π–π stacking inter­actions, with centroid–centroid separations of 3.897 (3) Å

Diffusion and mixing in gravity-driven dense granular flows

We study the transport properties of particles draining from a silo using imaging and direct particle tracking. The particle displacements show a universal transition from super-diffusion to normal diffusion, as a function of the distance fallen, independent of the flow speed. In the super-diffusive (but sub-ballistic) regime, which occurs before a particle falls through its diameter, the displacements have fat-tailed and anisotropic distributions. In the diffusive regime, we observe very slow cage breaking and Peclet numbers of order 100, contrary to the only previous microscopic model (based on diffusing voids). Overall, our experiments show that diffusion and mixing are dominated by geometry, consistent with fluctuating contact networks but not thermal collisions, as in normal fluids

Prirodna hrana acipenser persicus gajenog u ribnjačkim jezerima

A study on live food in Acipenser persicus rearing ponds was carried out In four rearing ponds; two in the Shahid Beheshti hatchery and two ponds in the Yousefpour hatchery. Samples were collected from three points in each pond on a weekly basis. Samples were collected using plankton nets (mesh size 50 µm), Ruthner sampler and Ekman grab. Zooplankton and benthic samples were fixed in 4 % formalin solution for later analysis. Zooplankton species identified in water samples collected at all four ponds belonged mainly to two phyla; Arthropoda and Rotifera. Total abundance of zooplankton species was estimated 87576 individuals L-1 in the Yousefpour hatchery and 136626 individuals L-1 in the Shahid Beheshti hatchery. Insect larvae, oligochaeta worms and mollusks were found in the sediment samples collected from the Yousefpour hatchery while sediment samples collected from the Shahid Beheshti hatchery contained only insect larvae and oligochaeta worms. The total abundance of benthic organisms was 0.343 g m-2 in the Yousefpour hatchery and 1.28 g m-2 in the Shahid Beheshti hatchery. Condition factor in fishes ranged from 0.29-0.54 in the Yousefpour hatchery and from 0.30-0.47 in the Shahid Beheshti hatchery