The Capsule Parachute Assembly System (CPAS) project has increased efforts to demonstrate the performance of fully integrated parachute systems at both higher dynamic pressures and in the presence of wake fields using a Parachute Compartment Drop Test Vehicle (PCDTV) and a Parachute Test Vehicle (PTV), respectively. Modeling the extraction and separation events has proven challenging and an understanding of the physics is required to reduce the risk of separation malfunctions. The need for extraction and separation modeling is critical to a successful CPAS test campaign. Current PTV-alone simulations, such as Decelerator System Simulation (DSS), require accurate initial conditions (ICs) drawn from a separation model. Automatic Dynamic Analysis of Mechanical Systems (ADAMS), a Commercial off the Shelf (COTS) tool, was employed to provide insight into the multi-body six degree of freedom (DOF) interaction between parachute test hardware and external and internal forces. Components of the model include a composite extraction parachute, primary vehicle (PTV or PCDTV), platform cradle, a release mechanism, aircraft ramp, and a programmer parachute with attach points. Independent aerodynamic forces were applied to the mated test vehicle/platform cradle and the separated test vehicle and platform cradle. The aero coefficients were determined from real time lookup tables which were functions of both angle of attack and sideslip. The atmospheric properties were also determined from a real time lookup table characteristic of the Yuma Proving Grounds (YPG) atmosphere relative to the planned test month.

关键词：气动力；攻角；跌落试验；动态压力

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Chemical reaction kinetic model of hydrogen production from DME partial oxidation by plasma reforming was found.Mole fractions of main products of DME partial oxidation by spark plasma as the function of inlet gas flow rate were calculated at atmospheric pressure and ambient temperature.Comparing the results of calculation and experiment,the model was proved to be correct,The mechanism research was done by the method of sensitivity analysis and rate of production.The reduced mechanism which includes 16 species and 13 radical reactions was done.The calculation results of reduced mechanism and detailed mechanism were close.The result shows that the reduced mechanism can be used in chemical reaction kinetic calculation of hydrogen production from DME partial oxidation by spark plasma reforming.

关键词：机制减少;灵敏度数据;二甲醚（DME）;等离子体

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The Mars Science Laboratory (MSL) Entry, Descent and Landing Instrumentation (MEDLI) hardware was a first-of-its-kind sensor system that gathered temperature and pressure readings on the MSL heatshield during Mars entry on August 6, 2012. MEDLI began as challenging instrumentation problem, and has been a model of collaboration across multiple NASA organizations. After the culmination of almost 6 years of effort, the sensors performed extremely well, collecting data from before atmospheric interface through parachute deploy. This paper will summarize the history of the MEDLI project and hardware development, including key lessons learned that can apply to future instrumentation efforts. MEDLI returned an unprecedented amount of high-quality engineering data from a Mars entry vehicle. We will present the performance of the 3 sensor types: pressure, temperature, and isotherm tracking, as well as the performance of the custom-built sensor support electronics. A key component throughout the MEDLI project has been the ground testing and analysis effort required to understand the returned flight data. Although data analysis is ongoing through 2013, this paper will reveal some of the early findings on the aerothermodynamic environment that MSL encountered at Mars, the response of the heatshield material to that heating environment, and the aerodynamic performance of the entry vehicle. The MEDLI data results promise to challenge our engineering assumptions and revolutionize the way we account for margins in entry vehicle design.

关键词：气动特性;飞船着陆;仪器;隔热

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Volcanic SO2 column amount and injection height retrieved from the Ozone Monitoring Instrument (OMI) with the Extended Iterative Spectral Fitting (EISF) technique are used to initialize a global chemistry transport model (GEOS-Chem) to simulate the atmospheric transport and lifecycle of volcanic SO2 and sulfate aerosol from the 2008 Kasatochi eruption, and to subsequently estimate the direct shortwave, top-of-the-atmosphere radiative forcing of the volcanic sulfate aerosol. Analysis shows that the integrated use of OMI SO2 plume height in GEOS-Chem yields: (a) good agreement of the temporal evolution of 3-D volcanic sulfate distributions between model simulations and satellite observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar with Orthogonal Polarisation (CALIOP), and (b) an e-folding time for volcanic SO2 that is consistent with OMI measurements, reflecting SO2 oxidation in the upper troposphere and stratosphere is reliably represented in the model. However, a consistent (approx. 25) low bias is found in the GEOS-Chem simulated SO2 burden, and is likely due to a high (approx. 20) bias of cloud liquid water amount (as compared to the MODIS cloud product) and the resultant stronger SO2 oxidation in the GEOS meteorological data during the first week after eruption when part of SO2 underwent aqueous-phase oxidation in clouds. Radiative transfer calculations show that the forcing by Kasatochi volcanic sulfate aerosol becomes negligible 6 months after the eruption, but its global average over the first month is -1.3W/sq m, with the majority of the forcing-influenced region located north of 20degN, and with daily peak values up to -2W/sq m on days 16-17. Sensitivity experiments show that every 2 km decrease of SO2 injection height in the GEOS-Chem simulations will result in a approx.25decrease in volcanic sulfate forcing; similar sensitivity but opposite sign also holds for a 0.03 m increase of geometric radius of the volcanic aerosol particles. Both sensitivities highlight the need to characterize the SO2 plume height and aerosol particle size from space. While more research efforts are warranted, this study is among the first to assimilate both satellite-based SO2 plume height and amount into a chemical transport model for an improved simulation of volcanic SO2 and sulfate transport.

关键词：二氧化硫； MODIS（辐射测量）；臭氧；大气环流

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The Geostationary Ocean Color Imager (GOCI) was launched by the Republic of Korea on 27 June 2010 and is the first geostationary ocean color sensor in orbit that provides coastal bio-optical properties (such as chlorophyll concentration, absorption and backscattering coefficients) at unprecedented high spatial and temporal resolution. GOCI has 8 spectral bands covering 2,500 km x 2,500 km (centered 130E, 36N) at 500 m spatial resolution. Unlike polar-orbiting satellites which provide only one or two images of the same geographic area per day, GOCI collects images every hour from 9am to 4pm (eight images per day). This high temporal resolution can lead to improved understanding of short time scale optical and bio-optical variability in the ocean surface. However, retrieving ocean color products accurately can be challenging particularly in turbid coastal waters due to imperfect atmospheric correction. In this study, we process GOCI data through US Naval Research Lab's Automated Processing System (APS) and the standard GOCI Data Processing System (GDPS) distributed by the Korea Ocean Satellite Center (KOSC), and compare the retrieved ocean color products from the two processing systems. We use corresponding Moderate Resolution Imaging Spectroradiometer (MODIS) images as the ground truth to assess the performance of the two processing systems. Since these sensors can retrieve Fluorescence Line Height (FLH) which is less sensitive to atmospheric correction and colored dissolved organic matter (CDOM), we also compare the FLH products from these sensors, in addition to other ocean color products. Furthermore, we demonstrate the use of hourly GOCI images to detect and track features such as sediment plumes and algal blooms in the ocean surface.

关键词：颜色;海洋表面;卫星图像地球轨道;大气校正

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关键词：科学卫星;算法;红外图像;纬度;线性度;海洋表面

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No abstract available.

关键词：气候；湿度；公众健康；大气环流模型；气候模型

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For half a century, CdZnTelCdTe has been investigated for producing radiation detectors. Albeit some success, detector performance and production yield issues remain. Most importantly, the basic science about the factors limiting the detector property and production yield is not understood. The goal of this program is to experimentally and theoretically understand these limiting factors. In addition, techniques will be developed to remove these factors. In this program, 160 CZT crystals have been grown to achieve the program goal. It is discovered that Cd vacancies and Te antisites (Te at Cd sites) are the two major defects that limit the performance of the CZT/CdTe detectors. The introduction of Zn in to the crystals is one way to reduce the density of Te antisites. A process to reduce Cd vacancies has been developed for the growth of CTZ crystals. Zn has been introduced into the crystals to reduce the densities of the Te antisites. Using these approaches, CTZ with Zn contents of 0, 4, 10, 15, and 20have been produced and detectors have been fabricated. The best detectors are produced in CZT grown with 10Zn and 1.5excess Te. The resolution of 57Co 122keV peak is less than 5at room temperature.

关键词：镉锌碲化物;辐射;密度;探测器;电导率;伽玛射线

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On August 5th 2012, The Mars Science Laboratory entry vehicle successfully entered Mars atmosphere and landed the Curiosity rover on its surface. A Kalman filter approach has been implemented to reconstruct the entry, descent, and landing trajectory based on all available data. The data sources considered in the Kalman filtering approach include the inertial measurement unit accelerations and angular rates, the terrain descent sensor, the measured landing site, orbit determination solutions for the initial conditions, and a new set of instrumentation for planetary entry reconstruction consisting of forebody pressure sensors, known as the Mars Entry Atmospheric Data System. These pressure measurements are unique for planetary entry, descent, and landing reconstruction as they enable a reconstruction of the freestream atmospheric conditions without any prior assumptions being made on the vehicle aerodynamics. Moreover, the processing of these pressure measurements in the Kalman filter approach enables the identification of atmospheric winds, which has not been accomplished in past planetary entry reconstructions. This separation of atmosphere and aerodynamics allows for aerodynamic model reconciliation and uncertainty quantification, which directly impacts future missions. This paper describes the mathematical formulation of the Kalman filtering approach, a summary of data sources and preprocessing activities, and results of the reconstruction.

关键词：大气层；降落轨迹；着陆地点；火星大气层；空气动力特性

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The culture, subsistence, and welfare of tropical Pacific Island Nation people are all in some way tied to their proximate fishery resources. Many of these fisheries are already under considerable stress and duress due to human practices such as overfishing, pollution and runoff, habitat destruction and degradation, lack of proper management protocols, and coastal and global population pressures. Other human activities such as fossil fuel use, deforestation and changes in land use and consequent emissions of gases and particulates, such as carbon dioxide, sulfur dioxide, methane, etc., to the atmosphere are contributing to alteration of the global climate by a general overall warming of the planetary atmosphere. The warming of the overlying atmosphere in turn warms the underlying surface ocean. In addition to the surface ocean warming, there is also the problem of ocean acidification owing to absorption of anthropogenic carbon dioxide by the surface waters of the ocean. This input of atmospheric carbon dioxide into the surface ocean reduces the surface water pH, which is detrimental to calcifying organisms such as those that are integral to coral reefs or the planktonic calcareous coccolithophoridae and foraminifera. Climate change and ocean acidification both have the capacity to impact simultaneously all organism trophic levels and so the possible negative ramifications can and should not be underestimated.

关键词：气候变化；海平面；酸化；污染

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