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The Visible Infrared Imaging Radiometer Suite (VIIRS) instruments on-board the Suomi National Polar-orbiting Partnership (S-NPP) and Joint Polar Satellite System (JPSS) spacecrafts 1 and 2 provides calibrated sensor data record (SDR) reflectance, radiance, and brightness temperatures for use in environment data record (EDR) products. The SDRs and EDRs are used in weather forecasting models, weather imagery and climate applications such as ocean color, sea surface temperature and active fires. The VIIRS has 22 bands covering a spectral range 0.4–12.4 µm with resolutions of 375 m and 750 m for imaging and moderate bands respectively on four focal planes. The bands are stratified into three different types based on the source of energy sensed by the bands. The reflective solar bands (RSBs) detect sunlight reflected from the Earth, thermal emissive bands (TEBs) sense emitted energy from the Earth and the day/night band (DNB) detects both solar and lunar reflected energy from the Earth. The SDR calibration uses a combination of pre-launch testing and the solar diffuser (SD), on-board calibrator blackbody (OBCBB) and space view (SV) on-orbit calibrator sources. The pre-launch testing transfers the National Institute of Standards and Technology (NIST) traceable calibration to the SD, for the RSB, and the OBCBB, for the TEB. Post-launch, the on-board calibrators track the changes in instrument response and adjust the SDR product as necessary to maintain the calibration. This paper will discuss the pre-launch radiometric calibration portion of the SDR calibration for the RSBs that includes the dynamic range, detector noise, calibration coefficients and radiometric uncertainties for JPSS-2 VIIRS.

The Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP) has successfully operated on-orbit for nearly ten years since its launch in October 2011, continuously making global observations and improving studies of changes in the Earth’s climate and environment. VIIRS has 22 spectral bands, among which 14 are reflective solar bands (RSBs) covering a spectral range from 0.41 to 2.25 μm. The SNPP VIIRS RSBs are primarily calibrated by the onboard solar diffuser (SD), with its on-orbit degradation tracked by an onboard SD stability monitor (SDSM). The near-monthly scheduled lunar observations, together with the sensor responses over stable ground targets, have contributed to the sensor’s mission-long on-orbit calibration and characterization. Numerous improvements have been made in the RSB calibration methodology since SNPP VIIRS was launched, and the RSB calibration has reached a mature stage after almost ten years of on-orbit operation. SNPP is a joint NASA/NOAA mission and there are two teams, the NASA VIIRS Calibration Support Team (VCST) and the NOAA VIIRS Sensor Data Record Team, which are dedicated to SNPP VIIRS on-orbit calibration. In this paper, we focus on the calibration performed by the NASA VCST. The SNPP VIIRS RSB calibration methodologies used to produce the calibration coefficient look up tables for the latest NASA Level 1B Collection 2 products are reviewed and the calibration improvements incorporated in this collection are described. Recent calibration changes include the removal of image striping caused by non-uniform degradation of the SD, improvements to the method for combining lunar and SD data, mitigation of the effects due a recent anomaly in the SD measurements, estimation of the SD degradation beyond 935 nm, and fitting strategy improvements for look-up table delivery. Overall, the SNPP VIIRS RSBs have performed well since its launch and continue to meet design specifications.

The willingness of public authority to delegate social and environmental regulation to the private sector has varied from sector to sector, but has often led to the establishment of ‘voluntary’ standards and certifications on sustainability. Many of these have taken the form of ‘stewardship councils’ and ‘sustainability roundtables’ and have been designed around a set of institutional features seeking to establish legitimacy, fend off possible criticism, and ‘sell’ certifications to potential users. The concept of ‘roundtabling’ emphasizes the fitting a variety of commodity-specific sustainability situations into a form that not only ‘hears more voices’ (as in ‘ multi -stakeholder’), but also portrays to give them equal standing at the table of negotiations ( round table), thus raising higher expectations on accountability, transparency and inclusiveness. In this article, I examine to what extent these expectations are being met through the comparative case study of two sustainability certifications in the biofuel industry – in the context of a wider set of experiences in the agro-food and forestry sectors. I show that ‘roundtabling’ entails an ever more complex web of governance systems and procedures to meet ‘good practice’ in standard setting and management. This is opening space for competing initiatives that are less democratic, quicker, and more aligned with industry interests to establish substantial presence in the market for sustainability certifications. These tend to more easily discriminate on the basis of size (against small players) and geography (against actors in the South). The article concludes with a reflection on what can be done, through appropriate regulation, to address this situation.

A &ldquo, nadir-only&rdquo, framework of the radiometric intercomparison of multispectral sensors using simultaneous nadir overpasses (SNOs) is examined at the 1-km regimes and below using four polar-orbiting multispectral sensors: the twin MODerate-resolution Imaging Spectroradiometer (MODIS) in the Terra and Aqua satellites, the Visible Imaging Infrared Radiometer Suite (VIIRS) in the Suomi National Polar-orbiting Partnership (SNPP) satellite, and the Ocean and Land Colour Instrument (OLCI) in the Sentinel-3A satellite. The study is carried out in the context of isolating the on-orbit calibration of the reflective solar bands (RSBs) under the &ldquo, restriction. With a homogeneity-ranked, sample size constrained procedure designed to minimize scene-based variability and noise, the overall approach successfully stabilizes the radiometric ratio and tightens the precision of each SNO-generated comparison event. Improvements to the multiyear comparison time series are demonstrated for different conditions of area size, sample size, and other refinements. The time series demonstrate the capability at 1% precision or better under general conditions but can attain as low as 0.2% in best cases. Solar zenith angle is examined not to be important in the &ldquo, framework, but the spectral mismatch between two bands can give rise to significant yearly modulation in the comparison time series. A broad-scaled scene-based variability of ~2%, the &ldquo, scaling phenomenon&rdquo, is shown to have pervasive presence in both northern and the southern polar regions to impact inter-RSB comparison. Finally, this paper highlights the multi-instrument cross-comparisons that are certain to take on a more important role in the coming era of high-performing multispectral instruments.

Este trabalho teve como objetivo propor uma metodologia para determinar o tempo de aeração no RSB necessário para oxidação da matéria orgânica facilmente biodegradável. A metodologia proposta consiste em aplicar o conceito de equações de diferenças não-lineares nos dados de taxa de consumo de oxigênio (TCO). Os dados experimentais utilizados no trabalho foram obtidos num RSB em escala de bancada. As médias do tempo para oxidação da matéria orgânica facilmente biodegradável foram 0,83, 0,83, 1,17 e 1,54 horas para as idades do lodo de 30, 20, 10 e 5 dias, respectivamente. Estes valores se mostraram semelhantes aos valores recomendados na literatura de lodos ativados. A metodologia ora proposta é de fácil aplicação aos dados de TCO e proporciona uma contribuição na busca de minimizar os custos operacionais do RSB. The purpose of this study was to propose a method to determine the aeration time needed in the SBR for oxidation of easily biodegradable organic matter. The method proposed consists of applying the concept of equations of non-linear differences to the data of oxygen utilization rate (OUR) The experimental data used in the study were obtained from a bench scale SBR. The mean times required for oxidation of easily degradable organic matter were 0.83, 0.83, 1.17 and 1.54 hours for sludges aged 30, 20, 10 and 5 days, respectively. These values were similar to the values recommended in the literature on activated sludges. The method proposed here is easy to apply to the OUR data and provides a contribution in seeking to minimize the operating costs of the SBR.

This paper presents the Robotics Service Bus (RSB), a new message-oriented, event-driven middleware based on a logically unified bus with hierarchical structure. Major goals for the development of RSB were openness and scalability in order to integrate diverse components in the context of robotics and intelligent systems. This includes the ability to operate on embedded platforms as well as desktop computers, reduction of framework lock-in, and the integration with other middlewares. We describe the design of the RSB middleware and explain how it meets requirements which lead to a scalable and open middleware concept. These requirements are based on several application scenarios which are used to verify the applicability of RSB. Furthermore, we relate RSB to other middlewares in the robotics domain.