Planting the Landscape

A landscape is an investment of time and money that can be a beautiful, functional, and satisfying living space. Gardeners and landscape managers implementing integrated pest management strategies through good judgment in plant selection, site preparation, and planting practices will reduce insect, disease, and wildlife damage and will help ensure the growth and longevity of the investment. Proper plant selection, site preparation, and planting practices are aspectsof integrated pest management. Continued integration of correct cultural practices is important through proper mulching, watering, fertilizing, and other management practices to reducepests

Lidar technology measurements and technology: Report of panel

Lidar is ready to make an important contribution to tropospheric chemistry research with a variety of spaceborne measurements that complement the measurements from passive instruments. Lidar can now be considered for near-term and far-term space missions dealing with a number of scientifically important issues in tropospheric chemistry. The evolution in the lidar missions from space are addressed and details of these missions are given. The laser availability for space missions based upon the technical data is assessed

A novel satellite mission concept for upper air water vapour, aerosol and cloud observations using integrated path differential absorption LiDAR limb sounding

We propose a new satellite mission to deliver high quality measurements of upper air water vapour. The concept centres around a LiDAR in limb sounding by occultation geometry, designed to operate as a very long path system for differential absorption measurements. We present a preliminary performance analysis with a system sized to send 75 mJ pulses at 25 Hz at four wavelengths close to 935 nm, to up to 5 microsatellites in a counter-rotating orbit, carrying retroreflectors characterized by a reflected beam divergence of roughly twice the emitted laser beam divergence of 15 µrad. This provides water vapour profiles with a vertical sampling of 110 m; preliminary calculations suggest that the system could detect concentrations of less than 5 ppm. A secondary payload of a fairly conventional medium resolution multispectral radiometer allows wide-swath cloud and aerosol imaging. The total weight and power of the system are estimated at 3 tons and 2,700 W respectively. This novel concept presents significant challenges, including the performance of the lasers in space, the tracking between the main spacecraft and the retroreflectors, the refractive effects of turbulence, and the design of the telescopes to achieve a high signal-to-noise ratio for the high precision measurements. The mission concept was conceived at the Alpbach Summer School 2010

Microstructure and wear behaviour of powder and suspension hybrid Al2O3–YSZ coatings

Suspension based plasma sprayed coatings can yield superior microstructural and tribological properties compared to conventional powder based plasma sprayed coatings. This study investigates a new hybrid method, using simultaneous spraying from powder and suspension, to produce composite coatings using alumina and yttria stabilised zirconia (YSZ), with potentially excellent wear and thermal properties. Dry sliding wear showed the alumina suspension-YSZ suspension coating yielded half the specific wear rate of the alumina powder-YSZ suspension, explained by preferential gamma alumina formation and increased porosity in the latter. Both YSZ-containing samples showed superior toughness and wear rate than simple alumina powder and suspension coatings

Detection of Greenhouse Gas Precursors from Diesel Engines Using Electrochemical and Photoacoustic Sensors

Atmospheric pollution is one of the worst threats to modern society. The consequences derived from different forms of atmospheric pollution vary from the local to the global scale, with deep impacts on climate, environment and human health. Several gaseous pollutants, even when present in trace concentrations, play a fundamental role in important processes that occur in atmosphere. Phenomena such as global warming, photochemical smog formation, acid rain and the depletion of the stratospheric ozone layer are strongly related to the increased concentration of certain gaseous species in the atmosphere. The transport sector significantly produces atmospheric pollution, mainly when diesel oil is used as fuel. Therefore, new methodologies based on selective and sensitive gas detection schemes must be developed in order to detect and monitor pollutant gases from this source. In this work, CO2 Laser Photoacoustic Spectroscopy was used to evaluate ethylene emissions and electrochemical analyzers were used to evaluate the emissions of CO, NOx and SO2 from the exhaust of diesel powered vehicles (rural diesel with 5% of biodiesel, in this paper called only diesel) at different engine rotation speeds. Concentrations in the range 6 to 45 ppmV for ethylene, 109 to 1,231 ppmV for carbon monoxide, 75 to 868 ppmV for nitrogen oxides and 3 to 354 ppmV for sulfur dioxide were obtained. The results indicate that the detection techniques used were sufficiently selective and sensitive to detect the gaseous species mentioned above in the ppmV range

Himawari-8 enabled real-time distributed PVsimulations for distribution networks

High resolution, next generation satellites such as Himawari-8 show great promise for the provision of accurate estimations of Behind-the-Meter (BtM) solar PV power production. This paper presents a methodology that produces real-time PV power estimates as derived from Himawari-8 satellite imagery, validating them against seven Australian radiation monitoring sites and 78 small-scale BtM solar PV sites in Canberra, Australia. We report an MBE of -7 W m-2 and RMSE of 55 W m-2 for global horizontal radiation values (Gh) and an MBE of 0.04 W/Wp and RMSE of 0.15 W/Wp for estimated actuals at the PV sites. As a capstone, we apply this satellite based radiation modeling tool to a distribution network level distributed PV simulation in a single case-study using 15,500 PV sites. This work was completed in collaboration with industry partner, Solcast

A tuning routine to correct systematic influences in reference PV systems' power outputs

Power output measurements from PV systems are subject to a wide variety of systematic external and internal influences, such as shading, soiling, degradation, module and inverter quality issues and other system-level losses. All of these influences upon PV power measurements make the use of PV power output datasets for higher-level analysis problematic, particularly in their use as reference PV systems for estimating the power of a regional portfolio. To address these issues, we present a three-step method. Firstly, a parameterisation and quality control of power measurements is performed, which also corrects for consistent inefficiencies by a loss factor LF. Secondly, the detection of systematic de-ratings affecting PV system power output differently for each time step of the day (predominantly due to shading) together with the implementation of a subsequent “re-rating” of the power output measurements in a process referred to as tuning. The pivotal element of this approach is a 30-day running 90th percentile of the clear-sky index for photovoltaics kpv and the computation of a daily de-rating profile. Lastly, high kpv related variance in the early morning and evening is detected and filtered. Whilst these three methods are independent of each other, we suggest applying them in combination following the same order as in our paper. Cross-validations of these methods demonstrate significant improvements to the PV power measurement profiles, particularly in their use as reference PV systems for upscaling approaches. The RMSE falls from 0.174 to 0.09 W/Wp, rRMSE from 46.5% to 21.9%, MAPE from 47.9% to 20.8% and the correlation r increases from 0.767 to 0.919. Hence, we report overall improvements to RMSE, rRMSE, MAPE and r by 48%, 53%, 57% and 20%, respectively

Comparing the capability of low- and high-resolution LiDAR data with application to solar resource assessment, roof type classification and shading analysis

LiDAR (Light Detection and Ranging) data have recently gained popularity for use in solar resource assessment and solar photovoltaics (PV) suitability studies in the built environment due to robustness at identifying building orientation, roof tilt and shading. There is a disparity in the geographic coverage of low- and high-resolution LiDAR data (LL and LH, respectively) between rural and urban locations, as the cost of the latter is often not justified for rural areas where high PV penetrations often pose the greatest impact on the electricity distribution network. There is a need for a comparison of the different resolutions to assess capability of LL. In this study, we evaluated and improved upon a previously reported methodology that derives roof types from a LiDAR-derived, low-resolution Digital Surface Model (DSM) with a co-classing routine. Key improvements to the methodology include: co-classing routine adapted for raw LiDAR data, applicability to differing building type distribution in study area, building height and symmetry considerations, a vector-based shading analysis of building surfaces and the addition of solar resource assessment capability. Based on the performance of different LiDAR resolutions within the developed model, a comparison between LL (0.5–1 pts/m2) and LH (6–8 pts/m2) LiDAR data was applied; LH can confidently be used to evaluate the applicability of LL, due to its significantly higher point density and therefore accuracy. We find that the co-classing methodology works satisfactory for LL for all types of building distributions. Roof-type identification errors from incorrect co-classing were rare (<1%) with LL. Co-classing buildings using LL improves accuracy of roof-type identification in areas with homogeneous distribution of buildings, here from 78% to 86% in accuracy. Contrastingly, co-classing accuracy using LH is marginally reduced for all building distributions from 94.8% to 94.4%. We adapt the Hay and Davies solar transposition model to include shading. The shading analysis demonstrates similarity of results between LL and LH. We find that the proposed methodology can confidently be used for solar resource assessments on buildings when only LiDAR data of low-resolution (<1 pts/m2) is available

US-INDIA TECHNICAL COLLABORATION TO PROMOTE REGIONAL STABILITY.

Two US-India documents were signed in 2000 that provided new impetus for scientific and technical cooperation between the two countries. The first document is the US-India Science and Technology Agreement, which is aimed at 'promoting scientific and technological cooperation between the people of their two countries.' The second is the US-India Joint Statement on Energy and Environment, which states 'the United States and India believe that energy and environment could be one of the most important areas of cooperation between the two countries.' In addition to the work already underway as part of these two agreements, the US Department of Energy (DOE) has established a US-India Science and Technology Initiative to utilize the expertise of DOE national laboratories to conduct activities that support US policy objectives in South Asia. PNNL and LANL are working with US government agencies to identify appropriate non-sensitive, non-nuclear areas for US-Indian technical collaboration. The objectives of such collaboration are to address visible national and international problems, build trust between the United States and India, and contribute to regional stability in South Asia. This paper describes the approach for this engagement, the Indian scientific organization and infrastructure, potential areas for collaboration, and current status of the initiative