Wind energy planning: Development and application of a site selection method for wind energy conversion systems (WECS)

The use of wind energy by means of its conversion to electricity involves a number of constrains such as economic, environmental, technical, legal, social and institutional requirements. Planning for wind energy should solve these issues in the planning process by encouraging opportunities and discouraging constraints associated with the use of wind energy. The opportunities and constraints significant at the regional level (i.e. approximately 10,000 km²) were identified, and a systematic method was developed to select sites for large WECS by incorporating the identified factors. These factors include: wind resource, proximity to load centres, proximity to tie-in points, and exclusive land-use areas. The developed method was applied to the western Massachusetts region, and the first results of the study have been acquired.     

Design of a memory‐based prefilter supplementing a robust PID control system

For systems with uncertainties, lots of PID parameter tuning methods have been proposed from the view point of the robust stability theory. However, the control performance becomes conservative using robust PID controllers. In this paper, a new two‐degree‐of‐freedom (2DOF) controller, which can improve the tracking properties, is proposed for nonlinear systems. According to the proposed method, the prefilter is designed as the PD compensator whose control parameters are tuned by the idea of a memory‐based modeling (MBM) method. Since the MBM method is a type of local modeling methods for nonlinear systems, PD parameters can be tuned adequately in an online manner corresponding to nonlinear properties. Finally, the effectiveness of the newly proposed control scheme is numerically evaluated on a simulation example. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

Improved fracture toughness and fatigue life of carbon fiber reinforced epoxy composite due to incorporation of rubber nanoparticles

In this study, core–shell rubber (CSR) nanoparticles with approximate particle size of 35 nm were used as a modifier for the epoxy polymer. The effects of various CSR contents in the epoxy matrix on mode I interlaminar fracture toughness, tensile strength, and fatigue life of the carbon fabric reinforced epoxy (CF/EP) composites were investigated. The experimental results showed that the mode I interlaminar fracture toughness at crack initiation and propagation significantly improved by 71.21 and 58.47 %, respectively, when 8.0 wt% CSR was dispersed in the epoxy matrix. The fatigue life of the modified CF/EP composites at all of CSR contents dramatically increased 75–100 times longer than that of the unmodified CF/EP composites at high cycle fatigue while tensile strength slightly increased by about 10 %. Field emission scanning electron microcopy (FESEM) observations of the fracture surfaces were conducted to explain failure mechanisms of CSR addition to the CF/EP composites. The evidences of the rubber nanoparticle debonding, plastic void growth, and microshear banding were credited for delaying the onset of matrix crack, and reducing the crack growth rate, as a result, attributed to increase in the mechanical properties of the CF/EP composites.     

Changes in high K+-evoked serotonin release and serotonin 2A/2C receptor binding in the frontal cortex of rats with thioacetamide-induced hepatic encephalopathy

Protein import into the nucleus is generally considered to involve specific nuclear localization signals (NLS) though it is becoming increasingly clear that efficient and well controlled import of proteins which lack a canonical NLS also occurs in cells. Human immunodeficiency virus type 1 (HIV-1) Vpr is one such protein which does not have an identifiable canonical NLS and yet efficiently localizes to the nuclear compartment. Here, we use confocal microscopy to demonstrate that mutations in the putative central hydrophobic helix of Vpr result in the retention of the protein in highly localized ring-like structures around the nuclear periphery with striking impairment in their ability to enter the nuclear interior. By characterizing other biological activities associated with this protein, such as its ability to incorporate into budding virions and its ability to arrest cells in G2, we show that this helical domain is specific for the nuclear translocation of the protein with very little effect on these other functions. Interestingly, however, perturbation of this helical motif also perturbs the protein's ability to augment viral replication in primary human macrophages indicating that the integrity of this secondary structure is essential for optimal infection in these non-dividing cells.     

Effective Dissolution of Platinum by Using Chloride Salts in Recovery Process

Platinum (Pt) is typically recovered by employing dissolution processes in aqueous solutions; however, these processes require a long processing time and considerable quantities of acids with strong oxidants owing to the high chemical stability of Pt. In order to develop an efficient dissolution process, we studied chlorination treatments for Pt prior to dissolution. Chlorination was carried out at 673?K to 873?K (400?°C to 600?°C) using copper(II) chloride (CuCl₂) as a chlorine source. While pure Pt was insoluble in hydrochloric acid (HCl(aq)), the entire Pt component of the treated sample dissolved in HCl(aq) under certain conditions. Therefore, the proposed method can be used as a new, environmental friendly Pt recovery process.     

Quantitative risk assessment of noroviruses in drinking water based on qualitative data in Japan

Noroviruses are one of the major causes of viral gastroenteritis in Japan. A quantitative risk assessment was conducted to evaluate the health risk caused by this virus in drinking water. A Monte Carlo analysis was used to calculate both the probability of infection and the disease burden using disability-adjusted life years (DALYs). The concentration of noroviruses in tap water was estimated based on qualitative data and a most probable number (MPN) method with an assumed Poisson lognormal distribution. This numerical method was evaluated using two sets of available count data of Cryptosporidium: that collected from a river and that found in tap water in Japan. The dose-response relationships for noroviruses were estimated using assumed ID50 (10 or 100). The annual risk was higher than the US-EPA acceptable level (10(-4) [infection/ person-year]) but around the WHO level (10(-6) [DALYs/ person-year]). As suggested by others, since microbial concentrations are generally lognormally distributed, the arithmetic mean was directly related to the annual risk, suggesting that the arithmetic mean is more useful in representing the degree of microbial contamination than the geometric mean.     

Tomakomai Large Scale Crude Oil Fire Experiments

This paper summarizes the results of large-scale crude oil fire experiments conducted in Tomakomai, Japan, in 1998 to obtain information that could be applied to the development of firefighting strategies for, and the design of, huge petroleum storages. Arabian light-equivalent crude oil was burned in pans 5-, 10-, and 20-m in diameter. Most of the experiments were performed under favorable conditions. Measured data include external radiation, infrared image of the flame, flame temperature, gas concentration inside the flame, and other burning characteristics. The height of the strongest radiant emittance was H/D=0.1 to 0.2, where D=pan diameter and H=height from the initial fuel surface, and a kind of fireball appeared occasionally at the intermittant flame zone. Emitted smoke particles were sampled on the ground and observed with a scanning electron micrograph, and the distribution of the diameters of primary smoke particles was examined. The average diameter of primary smoke particles is 53.0 (±10.5)nm. The dependence of burning characteristics and flame structure on pan diameter is discussed. The flame height of the 20-m diameter pan fire is 1.9 (±0.3) D. The burning rate increases as the pan diameters increase, but the radiative fraction decreases as pan diameter increases.