scholarly journals MISSION PROFILE AND DESIGN CHALLENGES FOR MARS LANDING EXPLORATION

Author(s):  
J. Dong ◽  
Z. Sun ◽  
W. Rao ◽  
Y. Jia ◽  
L. Meng ◽  
...  

An orbiter and a descent module will be delivered to Mars in the Chinese first Mars exploration mission. The descent module is composed of a landing platform and a rover. The module will be released into the atmosphere by the orbiter and make a controlled landing on Martian surface. After landing, the rover will egress from the platform to start its science mission. The rover payloads mainly include the subsurface radar, terrain camera, multispectral camera, magnetometer, anemometer to achieve the scientific investigation of the terrain, soil characteristics, material composition, magnetic field, atmosphere, etc. The landing process is divided into three phases (entry phase, parachute descent phase and powered descent phase), which are full of risks. There exit lots of indefinite parameters and design constrain to affect the selection of the landing sites and phase switch (mortaring the parachute, separating the heat shield and cutting off the parachute). A number of new technologies (disk-gap-band parachute, guidance and navigation, etc.) need to be developed. Mars and Earth have gravity and atmosphere conditions that are significantly different from one another. Meaningful environmental conditions cannot be recreated terrestrially on earth. A full-scale flight validation on earth is difficult. Therefore the end-to-end simulation and some critical subsystem test must be considered instead. The challenges above and the corresponding design solutions are introduced in this paper, which can provide reference for the Mars exploration mission.

Author(s):  
M. P. Golombek ◽  
J. A. Grant ◽  
T. J. Parker ◽  
D. M. Kass ◽  
J. A. Crisp ◽  
...  

2010 ◽  
Vol 6 (1) ◽  
pp. 15
Author(s):  
James P Earls ◽  
Jonathon A Leipsic ◽  
◽  

Recent reports have raised general awareness that cardiac computed tomography (CT) has the potential for relatively high effective radiation doses. While the actual amount of risk this poses to the patient is controversial, the increasing concern has led to a great deal of research on new CT techniques capable of imaging the heart at substantially lower radiation doses than was available only a few years ago. Methods of dose reduction include optimised selection of user-defined parameters, such as tube current and voltage, as well as use of new technologies, such as prospective triggering and iterative reconstruction. These techniques have each been shown to lead to substantial reduction in radiation dose without loss of diagnostic accuracy. This article will review the most frequently used and widely available methods for radiation dose reduction in cardiac CT and give practical advice on their use and limitations.


2015 ◽  
Vol 10 (1) ◽  
pp. 5-25 ◽  
Author(s):  
Jack L. Winstead ◽  
Mitchell R. Wenger

ABSTRACT This study investigates whether AIS instructors' selection of topics adequately prepares graduates for the expectations of employers seeking candidates who can adapt to the pace of technological change. As businesses adopt new technologies, stakeholders of the accounting profession must periodically reassess educational needs in the area of accounting information systems (AIS). Because AIS is a field that encompasses a wide variety of conceptual and skill-based topics, the selection of course topics can result in a “gap” between what academics and CPA firms expect from new accountants. Given the variety of topic areas, do academics and CPAs agree on which ones to emphasize, or what levels of proficiency are appropriate for each topic? In this study, academics and accountants, primarily in public practice, completed identical surveys regarding desired levels of proficiencies. The results suggest agreement on desired levels of proficiency regarding computer operation and use of accounting software to complete basic tasks and create reports, while suggesting differences of opinion in six other areas (understanding business cycles in an electronic environment, understanding data-sharing technologies, using XBRL, comprehending business needs and how technology could solve problems, understanding e-commerce, and the basics of safeguarding electronic accounting records). Participants concluded by offering observations about the strengths and weaknesses of newly employed accountants.


2021 ◽  
Vol 217 (6) ◽  
Author(s):  
Wei Yan ◽  
Jianjun Liu ◽  
Xin Ren ◽  
Chunlai Li ◽  
Qiang Fu ◽  
...  

AbstractHigh-resolution optical cameras have always been important scientific payloads in Mars exploration missions, which can obtain detailed images of Martian surface for the study of geomorphology, topography and geological structure. At present, there are still many challenges for Mars high-resolution images in terms of global coverage, stereo coverage (especially for colour images), and data processing methods. High Resolution Imaging Camera (HiRIC) is a high-quality, multi-mode, multi-functional, multi-spectral remote sensing camera that is suitable for the deep space developed for China’s first Mars Exploration Mission (Tianwen-1), which was successfully launched in July 2020. Here we design special experiments based on the in-orbit detection conditions of Tianwen-1 mission to comprehensively verify the detection capability and the performance of HiRIC, from the aspects of image motion compensation effect, focusing effect, image compression quality, and data preprocessing accuracy. The results showed that the performance status of HiRIC meets the requirements of obtaining high resolution images on the Martian surface. Furthermore, proposals for HiRIC in-orbit imaging strategy and data processing are discussed to ensure the acquisition of high-quality HiRIC images, which is expected to serve as a powerful complementation to the current Mars high-resolution images.


2017 ◽  
Vol 107 (03) ◽  
pp. 124-128
Author(s):  
L. Merkel ◽  
J, Starz ◽  
C. Schultz ◽  
S. Braunreuther ◽  
G. Prof. Reinhart

Digitale Assistenzsysteme in der Produktion helfen, zunehmend komplex werdende Arbeitsaufgaben zu beherrschen. Dafür entstehen im Zuge der Digitalisierung der Produktion forschungsseitig zahlreiche neue Möglichkeiten individueller Werkerunterstützung. Das hier vorgestellte entwickelte Modell gestattet eine detaillierte Beschreibung der Fähigkeiten und Technologien von Komponenten eines Assistenzsystems. Durch einen Abgleich von spezifischen Anforderungen eines Anwendungsfalls mit den Fähigkeiten des Assistenzsystems soll die Auswahl eines geeigneten Assistenzsystems ermöglicht werden.   Digital assistance systems help to master tasks with growing complexity in production. Currently, a lot of research aims at developing new technologies for individual worker support. This paper presents a model for a detailed description of capabilities and technologies used for components in assistance systems. By matching a given task’s requirements with the capabilities of an assistance system, the selection of the best fitting assistance system can be achieved.


2021 ◽  

The use of big data is becoming increasingly important across the tourism sector and the value chain. With this publication, UNWTO intends to provide a baseline research on using big data by tourism and culture stakeholders, in order to improve the competitiveness of cultural tourism and reinforce its sustainability. The study sets the basis to connect tourism, culture and new technologies for mutual benefits, while calling for a reflection on the ethical implications for policymakers, businesses and end-users. The selection of case studies illustrates the most frequent case-scenarios of the use of big data in cultural tourism within destinations, compiled during the research. As the new technologies are facing ever-evolving scenarios, their use will be harnessed by the tourism sector in its endeavour to innovate and provide new cultural experiences.


2018 ◽  
Vol 32 (1) ◽  
Author(s):  
Bharat S. Parekh ◽  
Chin-Yih Ou ◽  
Peter N. Fonjungo ◽  
Mireille B. Kalou ◽  
Erin Rottinghaus ◽  
...  

SUMMARYHIV diagnostics have played a central role in the remarkable progress in identifying, staging, initiating, and monitoring infected individuals on life-saving antiretroviral therapy. They are also useful in surveillance and outbreak responses, allowing for assessment of disease burden and identification of vulnerable populations and transmission “hot spots,” thus enabling planning, appropriate interventions, and allocation of appropriate funding. HIV diagnostics are critical in achieving epidemic control and require a hybrid of conventional laboratory-based diagnostic tests and new technologies, including point-of-care (POC) testing, to expand coverage, increase access, and positively impact patient management. In this review, we provide (i) a historical perspective on the evolution of HIV diagnostics (serologic and molecular) and their interplay with WHO normative guidelines, (ii) a description of the role of conventional and POC testing within the tiered laboratory diagnostic network, (iii) information on the evaluations and selection of appropriate diagnostics, (iv) a description of the quality management systems needed to ensure reliability of testing, and (v) strategies to increase access while reducing the time to return results to patients. Maintaining the central role of HIV diagnostics in programs requires periodic monitoring and optimization with quality assurance in order to inform adjustments or alignment to achieve epidemic control.


Nafta-Gaz ◽  
2021 ◽  
Vol 77 (3) ◽  
pp. 208-214
Author(s):  
Michał Pajda ◽  
◽  
Wojciech Mazela ◽  

The aim of the work was to present the issue of eco-efficiency, based on the PN-EN ISO 14045:2012 standard in relation to the production of fatty acid methyl esters (FAME). The ecoefficiency analysis takes into account economic and environmental aspects in the improvement of products and processes / technologies. Eco-efficiency considers the product and technology throughout the life cycle, from the construction phase, through use to decommissioning. The impact on the natural environment is assessed on the basis of: consumption of energy, materials, dust and gas emissions, waste and sewage. Total costs include: production costs, raw material costs, costs during the use phase including maintenance, repair and operating costs, product disposal or recycling. The eco-efficiency analysis is helpful in making decisions regarding the selection of a new product or designing a new technology, and enables the selection of the variant that is the most economical and has the least possible impact on the natural environment. These issues are particularly important in the case of biofuels. The rapid growth of their production and the European Union’s policy, which aims to increase the share of energy from renewable sources, cause concerns of many experts regarding the threats related to the production of biofuels, both for the environment and food security. In particular, efforts are made to minimize the amount of waste and residues by implementing the idea of a circular economy. This approach promotes the development of new technologies that are more environmentally friendly. Due to the regulations set out in the RED and RED II Directives, there is a chance that the biofuels will have a less negative impact on the environment. This results from the obligation to certify compliance with the sustainability criteria, which is carried out by voluntary systems recognized by the European Commission, such as the KZR INiG System.


2021 ◽  
Vol 70 (09) ◽  
pp. 7-13
Author(s):  
Şahlar Mahmud oğlu Babayev ◽  
◽  
Camaləddin Ələkbər oğlu Məmmədov ◽  
Səfiyyə İbrahim qızı Məhərrəmova ◽  
◽  
...  

The article is devoted to the development of technologies for the production of quality sowing material, which is the main problem of cotton growing, which has a greater share in the agricultural sector, which is the basis of the economy of the republic. For this purpose, a new technology for the production of sowing material was developed as a result of the selection of biologically mature yarns during the combined sorting of fibrous cotton yarns, as well as processing of these yarns by the proposed method, and two positive decisions were made by the Intellectual Property Agency. In addition to the mentioned advantages of the proposed technology, the use of low-percentage starch solution, as well as absorbents with high absorption capacity (zeolite or bentonite) in the country to improve the quality of sowing material in the production of sowing material as a result of processing raw materials. indicates that it has indicators. Key words: fiber, cotton, yarn, combined, sorting, sowing material, production, technology


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