scholarly journals MMX geodesy investigations: science requirements and observation strategy

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Koji Matsumoto ◽  
Naru Hirata ◽  
Hitoshi Ikeda ◽  
Toru Kouyama ◽  
Hiroki Senshu ◽  
...  
Keyword(s):  
Mass Distribution ◽  
Early Stage ◽  
Satellite Orbit ◽  
Rotation Parameter ◽  
Moments Of Inertia ◽  
Operational Strategies ◽  
Origin And Evolution ◽  
Observation Strategy ◽  
Landing Sites ◽  
Imaging Strategy

AbstractIn order to investigate the origin of Phobos and Deimos, the Japanese Martian Moons eXploration (MMX) mission is scheduled for launch in 2024. MMX will make comprehensive remote-sensing measurements of both moons and return regolith samples from Phobos to Earth. Geodetic measurements of gravity, shape, and rotation parameter of a body provides constraints on its internal structure reflecting its origin and evolution. Moments of inertia are important parameters to constrain the internal mass distribution, but they have not been well determined for the Martian moons yet. We discuss the mission requirements related to the moments of inertia to detect a potential heterogeneity of the mass distribution inside Phobos. We introduce mission instruments and operational strategies to meet the mission requirements. We present a preliminary imaging strategy from a quasi-satellite orbit for a base shape model that is expected to be created at the early stage of the mission. Geodetic products including ephemeris, gravity field, rotation parameter of Phobos, and spacecraft orbit are of importance not only for the geodetic study, but also for interpreting data from various mission instruments and selecting possible landing sites. Graphical Abstract

Controlling metalimnetic bloom of Planktothrix rubescens by a novel water withdrawal strategy: a modelling study

2021 ◽  
Author(s):  
Chenxi Mi ◽  
Marieke Frassl ◽  
David Hamilton ◽  
Tom Shatwell ◽  
Xiangzhen Kong ◽  
...  
Keyword(s):  
Early Stage ◽  
Management Strategies ◽  
Water Withdrawal ◽  
Light Extinction ◽  
Quality Model ◽  
Operational Strategies ◽  
Planktothrix Rubescens ◽  
Flushing Rate ◽  
Toxic Species ◽  
Lakes And Reservoirs

<p>Aggregations of cyanobacteria in lakes and reservoirs are commonly associated with surface blooms, but may also occur in the metalimnion as subsurface or deep chlorophyll maxima. Metalimnetic cyanobacteria blooms are of great concern when potentially toxic species, such as Planktothrix rubescens (P. rubescens), are involved. Apparently, metalimnetic blooms of P. rubescens have increased in frequency and severity in recent years so there is a strong need to establish the external factors controlling its growth. We hypothesized that P. rubescens blooms in reservoirs can be managed by modifying the water withdrawal strategy and altering the light climate experienced by the algae. We tested our hypothesis in Rappbode Reservoir by establishing a series of withdrawal and light scenarios based on a calibrated water quality model (CE-QUAL-W2). Our scenarios demonstrated that metalimnetic water withdrawal reduced P. rubescens biomass in the reservoir. According to the simulation results we defined an optimal withdrawal volume to control P. rubescens blooms in the reservoir as approximately 10 million m<sup>3</sup> during its blooming period. The numerical results also indicated that P. rubescens growth can be most effectively suppressed if the metalimnetic withdrawal is applied in the early stage of its rapid growth (i.e. before the occurrence of blooms). Additionally, the results showed that P. rubescens biomass gradually decreased with increasing light extinction and nearly disappeared when the extinction coefficient exceeded 0.55 m<sup>-1</sup>.  Our results indicated that close linkages among in situ measurements, model simulations, empirical growth rate and flushing rate calculations could inform management strategies to minimise the harmful impacts of P. rubescens in water supplies. Such a strategy could be used in reservoir operational strategies as an adaptation way to offset the rise in P. rubescens populations that has been linked to climate change.</p>

scholarly journals Synthesis of geochemical techniques to identify the origin and multistage evolution of saline water in a complex geothermal system

2019 ◽  
Vol 98 ◽  
pp. 08005 ◽  
Author(s):  
Yinlei Hao ◽  
Zhonghe Pang ◽  
Tianming Huang ◽  
Yanlong Kong ◽  
Jiao Tian ◽  
...  
Keyword(s):  
Early Stage ◽  
Saline Water ◽  
Eastern China ◽  
Sulfide Oxidation ◽  
Geothermal Water ◽  
Shallow Aquifer ◽  
Geothermal System ◽  
Geothermal Systems ◽  
Origin And Evolution ◽  
A Minor

Elucidating brine origin and evolution is a fundamental but not easy task especially for coastal geothermal systems with possible marine constituents and multistage evolution, as subsequently physical, chemical and biological alteration processes may mask the original and early-stage signatures. Here chemical and isotopic characteristics of water (D and 18O) and dissolved constituents (13C, 14C, 11B and 87Sr/86Sr) have been utilized to investigate the source and multistage evolution of the Jimo coastal geothermal system in eastern China, with dramatic differences of geochemical characteristics observed within a 0.2 km2 area. Results show that geothermal water is derived from paleo-meteoric water and has undergone a 3-stages evolution that involves: (1) Dissolution of marine halite and potash salts in the deep reservoir; (2) Water-rock reactions especially cation exchange produces a Cl-Na-Ca type water as deep geothermal water upwells along the fault zone; (3) A minor (<0.3%) addition of fossil seawater to the shallow aquifer that produces Cl-Na type waters in the west, whereas sulfide oxidation and dissolution of aluminosilicate and carbonates in the east produces Cl-Na-Ca type waters. The methodology utilized in this study offers a means of examining other similar complex geochemical systems having a multistage evolution.

National Champions, Reforms, and Industrial Policy in China

2020 ◽  
pp. 715-748
Author(s):  
Chen Li ◽  
Muyang Chen
Keyword(s):  
Industrial Policy ◽  
Early Stage ◽  
Business Groups ◽  
Central State ◽  
Origin And Evolution ◽  
Large State ◽  
Business System ◽  
National Champions ◽  
The Government ◽  
Current Governance

China’s economic reforms since the late 1970s have been characterized by a combination of market-oriented transition and persistent practices of statist industrial policy. A key dimension of China’s industrial policy is to transform and consolidate the backbone of its large state-owned enterprises sector into a group of globally competitive big businesses. The rise of China’s ‘national champions’, defined here as the giant central state-controlled corporations, business groups, and financial institutions in the ‘commanding heights’ sectors, has reshaped the landscape of China’s business system. This chapter reviews the origin and evolution of China’s national champions industrial policy. It examines how the Chinese state has restructured the core assets and enterprise units from the socialist command economy into a set of large state-controlled corporations and business groups viable in a predominantly market-oriented environment. This process has been driven by continuous organizational learning and capability building at both the government and enterprise levels. The current governance regime of China’s national champions can be characterized as a networked hierarchy that interweaves multiple mechanisms of institutional bridging and reciprocal control. Despite their remarkable size and growth, China’s national champions are still at an early stage of developing their international competitiveness.

scholarly journals Design of telescopic nadir imager for geomorphology (TENGOO) and observation of surface reflectance by optical chromatic imager (OROCHI) for the Martian Moons Exploration (MMX)

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Shingo Kameda ◽  
Masanobu Ozaki ◽  
Keigo Enya ◽  
Ryota Fuse ◽  
Toru Kouyama ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Satellite Orbit ◽  
Surface Reflectance ◽  
Wide Angle ◽  
Material Distribution ◽  
Scientific Objective ◽  
Spectral Mapping ◽  
Landing Sites ◽  
Geomorphological Features ◽  
Filter Wheel

AbstractThe JAXA’s Martian Moons Exploration (MMX) mission is planned to reveal the origin of Phobos and Deimos. It will remotely observe both moons and return a sample from Phobos. The nominal instruments include the TElescopic Nadir imager for GeOmOrphology (TENGOO) and Optical RadiOmeter composed of CHromatic Imagers (OROCHI). The scientific objective of TENGOO is to obtain the geomorphological features of Phobos and Deimos. The spatial resolution of TENGOO is 0.3 m at an altitude of 25 km in the quasi-satellite orbit. The scientific objective of OROCHI is to obtain material distribution using spectral mapping. OROCHI possesses seven wide-angle bandpass imagers without a filter wheel and one monochromatic imager dedicated to the observation during the landing phase. Using these two instruments, we plan to select landing sites and obtain information that supports the analysis of return samples. Graphical Abstract

scholarly journals Design of Telescopic Nadir Imager for Geomorphology (TENGOO) and Observation of Surface Reflectance by Optical Chromatic Imager (OROCHI) for the Martian Moons Exploration (MMX)

2021 ◽  
Author(s):  
Shingo Kameda ◽  
Masanobu Ozaki ◽  
Keigo Enya ◽  
Ryota Fuse ◽  
Toru Kouyama ◽  
...  
Keyword(s):  
Satellite Orbit ◽  
Surface Reflectance ◽  
Wide Angle ◽  
Material Distribution ◽  
Scientific Objective ◽  
Spectral Mapping ◽  
Sample Return ◽  
Landing Sites ◽  
Geomorphological Features ◽  
Filter Wheel

Abstract The JAXA’s Martian Moons Exploration (MMX) mission is planned to reveal the origin of Phobos and Deimos. Both moons will be observed by remote sensing. Sample return from Phobos will be performed. The nominal instruments were selected, including the telescopic nadir imager for geomorphology (TENGOO) and optical radiometer composed of chromatic imagers (OROCHI). The scientific objective of TENGOO is to obtain the geomorphological features of Phobos and Deimos. The spatial resolution of TENGOO is 0.3 m at an altitude of 25 km in the quasi-satellite orbit. The scientific objective of OROCHI is to obtain material distribution using spectral mapping. OROCHI is composed of seven wide-angle bandpass imagers without a filter wheel and one monochromatic imager dedicated to the observation during the landing phase. Using these two instruments, we plan to select landing sites and obtain information that supports the analysis of return samples.

scholarly journals In vivo three-dimensional evaluation of tumour hypoxia in nasopharyngeal carcinomas using FMT-CT and MSOT

2019 ◽  
Vol 47 (5) ◽  
pp. 1027-1038
Author(s):  
Wenhui Huang ◽  
Kun Wang ◽  
Yu An ◽  
Hui Meng ◽  
Yuan Gao ◽  
...  
Keyword(s):  
High Resolution ◽  
Early Stage ◽  
Three Dimensional ◽  
High Sensitivity ◽  
Immunohistochemical Analysis ◽  
Molecular Probe ◽  
Imaging Method ◽  
Tumour Hypoxia ◽  
Imaging Strategy

Abstract Purpose Accurate evaluation of hypoxia is particularly important in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. The aim of this study was to propose a novel imaging strategy for quantitative three-dimensional (3D) evaluation of hypoxia in a small animal model of NPC. Methods A carbonic anhydrase IX (CAIX)-specific molecular probe (CAIX-800) was developed for imaging of hypoxia. Mouse models of subcutaneous, orthotopic, and spontaneous lymph node metastasis from NPC (5 mice per group) were established to assess the imaging strategy. A multi-modality imaging method that consisted of a hybrid combination of fluorescence molecular tomography-computed tomography (FMT-CT) and multispectral optoacoustic tomography (MSOT) was used for 3D quantitative evaluation of tumour hypoxia. Magnetic resonance imaging, histological examination, and immunohistochemical analysis were used as references for comparison and validation. Results In the early stage of NPC (2 weeks after implantation), FMT-CT enabled precise 3D localisation of the hypoxia biomarker with high sensitivity. At the advanced stage (6 weeks after implantation), MSOT allowed multispectral analysis of the biomarker and haemoglobin molecules with high resolution. The combination of high sensitivity and high resolution from FMT-CT and MSOT could not only detect hypoxia in small-sized NPCs but also visualise the heterogeneity of hypoxia in 3D. Conclusions Integration of FMT-CT and MSOT could allow comprehensive and quantifiable evaluation of hypoxia in NPC. These findings may potentially benefit patients with NPC undergoing radiotherapy in the future.

Mass distribution and moments of inertia in the outer shells of the Earth

Terra Nova ◽  
2012 ◽  
Vol 25 (1) ◽  
pp. 38-47
Author(s):  
Michele Caputo ◽  
Riccardo Caputo
Keyword(s):  
Mass Distribution ◽  
Moments Of Inertia ◽  
The Earth

Trading Places

2011 ◽  
Vol 35 (4) ◽  
pp. 543-570 ◽  
Author(s):  
Mathew J. Novak ◽  
Jason A. Gilliland
Keyword(s):  
Early Stage ◽  
Business Strategies ◽  
Retail Sector ◽  
Historical Gis ◽  
Origin And Evolution ◽  
The People ◽  
Modern Cities ◽  
High Degree ◽  
The Relationship ◽  
The City

The economies of modern cities are dependent on an advanced retail system; so too are the people who inhabit them. The origin and evolution of retailing in London, Canada, was studied using a historical geographic information system (GIS) to document the relationship between a city and its retail sector. Visualization and spatial-statistical techniques afforded by the historical GIS were implemented to study change over time. The locations of retailers and the types of the goods they sold were examined for four periods in the city’s early history: 1844, 1863, 1881, and 1916. The distances traveled to shop were also calculated for a variety of goods. The results indicate that the retail system was ingrained in the development of the city, showing marked locational patterns and a high degree of rationality in the shopkeepers' business strategies. Mapping the retail landscape in each era using historical GIS allowed for the examination of the relationship between retail and residential development in the growing city. While the downtown area remained the primary retail district for the city, considerable retail expansion also occurred at the urban periphery during this early stage of the city's development.

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