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Electrical energy consumption if reduced during peak hours can result in the deferment of generation, transmission and distribution capacity addition. The postponement of capacity addition, or “avoided cost” is of promising value to electric utilities who can redirect financial resources for other purposes due to these offset costs. The reduction in energy consumption is achievable through smart grid implementation. Therefore, the utilities need to investigate whether upgrading their grid system to make it smarter is economically justifiable or not. Electricity companies have used the smart grid maturity model to assess their rating/ranking in different domains. The paper provides a framework for establishing future strategies and work plans as they pertain to smart grid implementations. The objective of this paper is to evaluate the demand-side management (DSM), energy efficiency measures and distributed generation benefits of smart grid in Oman. The developed scenarios include grid enhancement, customer contribution to the grid and both of these options simultaneously. The scenarios are analyzed for peak reduction and their benefits are calculated in terms of avoided cost of generation, transmission, distribution, and environmental costs. [ABSTRACT FROM AUTHOR]

Purpose: Reirradiation has been proposed as an effective modality for recurrent central nervous system (CNS) malignancies in adults. We evaluated the toxicity and outcomes of CNS reirradiation in pediatric patients.Methods and Materials: The data from pediatric patients <21 years of age at the initial diagnosis who developed a recurrent CNS malignancy that received repeat radiation therapy (RT) across 5 facilities in an international pediatric research consortium were retrospectively reviewed.Results: Sixty-seven pediatric patients underwent CNS reirradiation. The primary diagnoses included medulloblastoma/primitive neuroectodermal tumor (n=20; 30%), ependymoma (n=19; 28%), germ cell tumor (n=8; 12%), high-grade glioma (n=9; 13%), low-grade glioma (n=5; 7%), and other (n=6; 9%). The median age at the first course of RT was 8.5 years (range 0.5-19.5) and was 12.3 years (range 3.3-30.2) at reirradiation. The median interval between RT courses was 2.0 years (range 0.3-16.5). The median radiation dose and fractionation in equivalent 2-Gy fractions was 63.7 Gy (range 27.6-74.8) for initial RT and 53.1 Gy (range 18.6-70.1) for repeat RT. The relapse location was infield in 52 patients (78%) and surrounding the initial RT field in 15 patients (22%). Thirty-seven patients (58%) underwent gross or subtotal resection at recurrence. The techniques used for reirradiation were intensity modulated RT (n=46), 3-dimensional conformal RT (n=9), stereotactic radiosurgery (n=4; 12-13 Gy × 1 or 5 Gy × 5), protons (n=4), combined modality (n=3), 2-dimensional RT (n=1), and brachytherapy (n=1). Radiation necrosis was detected in 2 patients after the first RT course and 1 additional patient after reirradiation. Six patients (9%) developed secondary neoplasms after initial RT (1 hematologic, 5 intracranial). One patient developed a secondary neoplasm identified shortly after repeat RT. The median overall survival after completion of repeat RT was 12.8 months for the entire cohort and 20.5 and 8.4 months for patients with recurrent ependymoma and medulloblastoma after reirradiation, respectively.Conclusions: CNS reirradiation in pediatric patients could be a reasonable treatment option, with moderate survival noted after repeat RT. However, prospective data characterizing the rates of local control and toxicity are needed. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a methodology and the results of a study carried out to evaluate the long-term load management benefits of smart grid in terms of avoided cost of generation, transmission and distribution in Sultanate of Oman. The avoided transmission and distribution (T&D) capacity cost is calculated indirectly using the concept of asset distribution in a power system. The savings in transmission and distribution losses and environmental benefits are also estimated. These benefits are then compared with an estimated cost of upgrading the grid to make it smarter. The results have shown that the long-term load management benefits of smart grid could outweigh the cost of upgrading the grid to make it smarter. [Copyright &y& Elsevier]

Abstract: With increased demand for thin gage flat metals, control of strip flatness or shape in cold rolling processes has become very important. To improve the flatness quality of cold rolled metal strip and sheet, this work provides a rapid method to predict the transient strains (or stresses) occurring during the rewinding of flat-rolled steels having problematic asymmetric strip thickness profile (or wedge). Flatness control systems, used to monitor and correct the distribution of stress across the width of rolled sheet, are unable to distinguish between stresses induced during rolling, and those caused when rewinding strip containing asymmetric thickness profile. The winding stresses, unless large enough to plastically deform the strip, vanish upon unwinding during subsequent operations such as stamping. Therefore, to help avoid strip flatness defects in thin strip containing wedge, a method is developed to separate the winding stress contribution from the overall stresses that are measured indirectly by flatness control systems. A fourth-order polynomial Airy function is developed to rapidly predict the in-plane stresses based on mandrel wrap number and spatial location on the strip. The Airy function is obtained by applying two-dimensional finite element analysis to study the transient in-plane stresses during rewinding at various numbers of mandrel wraps for a strip containing wedge profile. Three-dimensional finite element analysis is first employed, however, to show justification to a simplified two-dimensional problem described by the plane-stress Airy function. The two-dimensional finite element analysis provides insight as to how the in-plane stresses evolve, and allows determination of coefficients for the Airy function based upon model geometry and displacement boundary conditions. This approach differs from other methods that employ Fourier series to solve the biharmonic equations for an assumed two-dimensional problem. Finally, filtering of the winding stresses from flatness control system input signals is also discussed based on data taken from a rolling mill different to that used for model development. [Copyright &y& Elsevier]

Abstract: Given Algerian’s abundant solar, wind resources, biomass, geothermal, etc. represent a potential market for renewable energy technologies. This article presents a review and the use of renewable energy situation in Algeria. The analysis of the present renewable energy situation and future objective are also discussed. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a study that estimated the DSM energy saving and load management potential in commercial and government/institutional sectors in Oman (central grid area) and evaluated its impact on generation capacity and energy savings. The end-use (lighting and air-conditioning) energy consumption data have been collected in two major segments of the commercial sector for simplicity and to save time and money. Another unique aspect of the study is the inclusion of the energy savings, in transmission and distribution (T&D) losses that are estimated by using generation expansion planning approach. The study has found that DSM is financially beneficial from customers’ point of view as the discounted payback period of investment in efficient lighting and air-conditioning is between 4 and 12 years of the surveyed sample. From the utility point of view the capacity saving at the horizon year is between 372 and 596MW and the overall energy saving for the whole planning horizon is about 29–44TWh. The total avoided cost in generation and capacity saving is somewhere between 416 and 597 million dollars. [Copyright &y& Elsevier]

Abstract: This paper presents a method to provide electrical connection to a 2D capacitive micromachined ultrasonic transducer (CMUT) array. The interconnects are processed after the CMUTs are fabricated on the front side of a silicon wafer. Connections to array elements are made from the back side of the substrate via highly conductive silicon pillars that result from a deep reactive ion etching (DRIE) process. Flip-chip bonding is used to integrate the CMUT array with an integrated circuit (IC) that comprises the front-end circuits for the transducer and provides mechanical support for the trench-isolated array elements. Design, fabrication process and characterization results are presented. The advantages when compared to other through-wafer interconnect techniques are discussed. [Copyright &y& Elsevier]

Abstract: The materno-fetal interface has for long been considered as an immune privileged biological site and thus understanding the mechanisms underlying fetal survival have been the focus of intense research. In adults, survivin and Stat-3 proteins are involved in tolerance as well as the induction of apoptosis. However, the role of these molecules in pregnancy and development has not been addressed. We have evaluated the expression of survivin and Stat-3 in allogeneic mouse models of low abortions (CBA/J×Balb/c), abortion prone (CBA/J×DBA/2J) and stress-triggered abortions from DBA/2J-mated CBA/J mice. We show that survivin is over-expressed in abortion-prone mating on gestation day 7.5. This effect was also found in stress-exposed mice, whereas expression was low in normal pregnancy mice. The phosphorylated Stat-3 (p-Stat-3) was down regulated in high abortion mating compared with low abortion mating, CBA/J×Balb/c. The level of apoptosis was similar in the three groups studied. Our results suggest that high expression of survivin and low expression of p-Stat-3 are involved in pregnancy loss in mice. [Copyright &y& Elsevier]

Abstract: The electricity tariffs in Oman are subsidized and are based on a cost accounting approach and do not reflect the true cost incurred in generating, transmitting and distributing a kilowatt-hour of electricity at the consumer end. This paper presents the electricity tariff based on the estimation of long-run marginal cost at generation, 33kV, and 415 voltage level for Ministry of Housing, Electricity & Water (MHEW) interconnected power system of Oman. The result shows that at the generation level a marginal kW costs US$ 75per year and a marginal kWh costs 2.07¢/kWh. These costs increase as we move downstream from generation to consumer end. The average cost of electricity at the consumer end connected at 415V is 6.52¢/kWh or 25.17Bz/kWh. [Copyright &y& Elsevier]

This paper reports the results of a local integrated resource planning (LIRP) study conducted for the Philippines. Based on the investment plans for serving loads at distribution feeders our key finding is that distributed resources (DR) are cost effective alternatives to supply capacity expansion for Cagayan Electric Power and Light Co. (CEPALCO), an investor-owned power distribution utility company operating in the Southern Philippines. The total cost savings for the selected feeder on which LIRP was performed are about 19 million Pesos (about half a million US dollars, 1998) over a 10-year period. [Copyright &y& Elsevier]

Abstract: Structural, electronic and optical properties of Ca x Cd1− x O (0⩽ x ⩽1) in rocksalt phase are calculated using full potential linearized augmented plane wave (FP-LAPW) method. The results show that the bandgap as well as structural and optical properties of the compound varies with the Ca concentration. The substitution of Cd by Ca, larger than 25%, transforms the ternary oxide from semi-metallic into indirect bandgap semiconductor. The bandgap increases with the increase in calcium while the bulk moduli decreases. The density of states shows that maximum contribution to the valence and conduction bands are due to the Cd-4d, O-2p, Ca-3p and Ca-3d states. Optical properties in the incident photon energy range 0–30eV reveal that the real part of the complex dielectric constant decreases with the increase in the Ca concentration. [Copyright &y& Elsevier]

Purpose Respiratory syncytial virus infection (RSVI) in lung transplant recipients (LTRs) has been associated with bronchiolitis obliterans syndrome (BOS) development and progression, but data have been derived from small studies. Methods This is a retrospective study of RSVI in LTRs at Duke University from Jan 2013 - May 2017. Decrement in FEV1 was determined by comparison of the FEV1 at 90 days post-RSVI to pre-RSVI baseline. Results Of 114 LTRs with RSVI, 15 had preexisting BOS and 99 did not have preexisting BOS. Those with preexisting BOS had a longer duration from transplant surgery to RSVI, more concomitant respiratory bacterial pathogens and less acute cellular rejection (ACR) within 90 days preceding RSVI compared to those without. Within 1-year of RSVI, 7/15 (46.7%) patients with preexisting BOS had BOS progression and 25/99 (25.3%) patients developed new BOS. In patients with documented FEV1 measured pre- and post-RSVI, 6/12 (50%) with preexisting BOS and 23/90 (25.5%) without preexisting BOS had FEV1 decline ≥ 5%. Kaplan-Meier analysis showed patients with decline in FEV1 ≥ 5% at 90 days post-RSVI had a higher 1-year mortality (p=0.003). Conclusion Our experience supports an increase in BOS development post-RSVI. While BOS progression post-RSVI was common in patients with pre-existing BOS, rates of progression were not greater than those described for the natural history of BOS post-lung transplant. FEV1 decline ≥ 5% at 90 days post-RSVI was associated with higher mortality regardless of BOS status prior to RSVI. [ABSTRACT FROM AUTHOR]