Automatic Detection of Clear-Sky Periods From Irradiance Data

Recent degradation studies have highlighted the importance of considering cloud cover when calculating degradation rates, finding more reliable values when the data are restricted to clear sky periods. Several automated methods of determining clear sky periods have been previously developed, but parameterizing and testing the models has been difficult. In this paper, we use clear sky classifications determined from satellite data to develop an algorithm that determines clear sky periods using only measured irradiance values and modeled clear sky irradiance as inputs. This method is tested on global horizontal irradiance (GHI) data from ground collectors at six sites across the United States and compared against independent satellite-based classifications. First, 30 separate models were optimized on each individual site at GHI data intervals of 1, 5, 10, 15, and 30 min (sampled on the first minute of the interval). The models had an average F0.5 score of 0.949 ± 0.035 on a holdout test set. Next, optimizations were performed by aggregating data from different locations at the same interval, yielding one model per data interval. This paper yielded an average F0.5 of 0.946 ± 0.037. A final, 'universal' optimization that was trained on data from all sites at all intervals provided an F0.5 score of 0.943 ± 0.040. The optimizations all provide improvements on a prior, unoptimized clear sky detection algorithm that produces F0.5 scores that average to 0.903 ± 0.067. Our paper indicates that a single algorithm can accurately classify clear sky periods across locations and data sampling intervals

EQUITABLE DISTRIBUTION OF DRINKING WATER SUPPLY IN MUNICIPAL CORPORATIONS IN THANE DISTRICT

Due to higher urbanization, water demand in six Municipal Corporations of Thane district is continuously increasing. The growth of the population, small and large industries, health and educational institutions, commercial units are the responsible factors. The demand of drinking water is continuously increasing but supply is not matching with increasing demand. Municipal Corporations have not made the provision of drinking water to the growing population on 24*7 basis. The alternative policies of rainwater harvesting, reducing leakages and wastage, more provision of funds for water supply projects, revision of tariff structure and private sector participation in distribution of drinking water supply will yield the better results in terms of growing demand of water supply.water supply, water demand

Multi-infeed HVDC/AC power system modeling and analysis with dynamic phasor application

In this paper, dynamic phasor method has been applied to HVDC transmission system and FACTS device modeling. A hybrid-model simulation algorithm is suggested for transient stability analysis with HVDC transmission system and FACTS devices in dynamic phasor models and other ac system elements in electromechanical models. Computer test results show clearly that the proposed hybrid-model simulation algorithm can be applied for transient stability analysis effectively and accurately. A multi-infeed HVDC/AC (MIDC/AC) system is studied using the suggested hybrid-model transient stability program. The dynamic behaviors of MIDC/AC system under different circumstances are discussed. The characteristics of HVDC system recovery and recovery strategy for MIDC system are considered in the stability analysis. Furthermore, the impacts of advanced FACTS controllers such as STATCOM on system dynamic are studied for enhance system operation security. © 2000 IEEE.published_or_final_versio

Metro Iloilo Development Council: In Pursuit of Managed Urban Growth

This paper aims to present the experience of MIDC in its pursuit for a highly livable region of God-loving and educated people working together for a progressive, self-reliant and sustainable community. It provides the socioeconomic development in Iloilo City, MIDCs core city and delves into urbanization issues and responses of Iloilo City in terms of resource mobilization and allocation, and delivery of basic services. It also gives a background on the creation of MIDC and highlights the experience of MIDC in working together towards the attainment of its vision

Optimal interpolation of satellite and ground data for irradiance nowcasting at city scales

We use a Bayesian method, optimal interpolation, to improve satellite derived irradiance estimates at city-scales using ground sensor data. Optimal interpolation requires error covariances in the satellite estimates and ground data, which define how information from the sensor locations is distributed across a large area. We describe three methods to choose such covariances, including a covariance parameterization that depends on the relative cloudiness between locations. Results are computed with ground data from 22 sensors over a 75×80 km area centered on Tucson, AZ, using two satellite derived irradiance models. The improvements in standard error metrics for both satellite models indicate that our approach is applicable to additional satellite derived irradiance models. We also show that optimal interpolation can nearly eliminate mean bias error and improve the root mean squared error by 50%

Thermodynamic phase diagram and phase competition in BaFe2(As1-xPx)2 studied by thermal expansion

High-resolution thermal-expansion and specific-heat measurements were performed on single crystalline BaFe2(As1-xPx)2 (0 < x < 0.33, x = 1). The observation of clear anomalies allows to establish the thermodynamic phase diagram which features a small coexistence region of SDW and superconductivity with a steep rise of Tc on the underdoped side. Samples that undergo the tetragonal-orthorhombic structural transition are detwinned in situ, and the response of the sample length to the magneto-structural and superconducting transitions is studied for all three crystallographic directions. It is shown that a reduction of the magnetic order by superconductivity is reflected in all lattice parameters. On the overdoped side, superconductivity affects the lattice parameters in much the same way as the SDW on the underdoped side, suggesting an intimate relation between the two types of order. Moreover, the uniaxial pressure derivatives of Tc are calculated using the Ehrenfest relation and are found to be large and anisotropic. A correspondence between substitution and uniaxial pressure is established, i.e., uniaxial pressure along the b-axis (c-axis) corresponds to a decrease (increase) of the P content. By studying the electronic contribution to the thermal expansion we find evidence for a maximum of the electronic density of states at optimal doping

Coexistence of incommensurate magnetism and superconductivity in Fe_{1+y}Se_xTe_{1-x}

We report an investigation into the superconducting and magnetic properties of Fe_{1+y}Se_{x}Te_{1-x} single crystals by magnetic susceptibility, muon spin rotation, and neutron diffraction. We find three regimes of behavior in the phase diagram for 0\leq x\leq 0.5: (i) commensurate magnetic order for x< 0.1, (ii) bulk superconductivity for $x\lesssim 0.1$, and (iii) a range \sim 0.25\leq x\leq 0.45 in which superconductivity coexists with static incommensurate magnetic order. The results are qualitatively consistent with a two-band mean-field model in which itinerant magnetism and extended s-wave superconductivity are competing order parameters.Comment: 4 pages, 4 figure