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The manned Mars exploration mission is an important application for the future use of heavy launch vehicle. With largger scale and more system, its launch site planning design and construction are difficult. Launch vehicle overall design, launch site planning design and test launch mode are considered as a whole of feedback iteration. For the huge system engineering of manned Mars exploration, the design of the launch site is mainly affected by the mission scale, launch vehicle overall design and test launch mode. Analysis of factors such as mission scale and window cycle, more than two heavy launch vehicle launch pads are needed for the manned Mars exploration mission. Therefore, it is necessary to consider the multi-pad construction. According to the preliminary genera parameters of heavy launch vehicle and the climate characteristics of Wenchang launch site, analysis the test launch mode that suitable for China’s heavy launch vehicle. And then, the horizontal planning and the vertical plannig method are suggestted for heavy launch vehicle launch site. Thereby achieving technically feasible, safe reliable and cost controllable purposes. Provid ideas and methods for China’s future large-scale space mission launch site planning.

A total of 23 polybrominated diphenyl ether (PBDE) congeners were measured in soil samples collected in areas with no known point source [urban/rural/background (U/R/B) sites] and in areas with known point source [brominated flame retardant (BFR)-related industrial sites (F sites) and e-waste recycling sites (E sites)] across five Asian countries. The highest PBDE concentrations were found in BFR-related industrial and e-waste recycling sites. The concentrations of PBDEs in U/R/B sites decreased in the following order: urban > rural > background sites. Total PBDE concentrations were dominated by BDE-209, while BDE-17, -85, -138, -191, -204, and -205 were the least abundant compounds. In both urban sites and rural sites, the mean concentrations of total PBDEs (∑23BDEs) in soils decreased in the following order: Japan > China > South Korea > India > Vietnam. The concentrations of PBDEs in soils were comparable with those reported in other studies. Among the three commercial PBDE mixtures, relatively large c...

With the development of network and information technology, it is highly desirable to create 3D geoscience applications in the network environment. However, construction of web-based 3D terrain model is one of the foundation works of 3D geoscience applications in the network environment. This paper presents a new method of constructing large-scale 3D terrain model based on Extensible 3D (X3D). In this way, we first use Geospatial components of X3D to build 3D terrain model by using DEM as the data source, then we publish the 3D terrain model to the internet with a architecture of Brower/Server and plug-in technology. To promote the display performance of large-scale 3D terrain model, We presents an approach that using the Level of Detail (LOD) technology to simplify the 3D terrain model. The application results show that the method this paper presented has advantage of easy to integrate with other network system, thereby easy to realize data sharing and interoperation; the method also has virtues of fast display speed, high ability of interaction. It’s an effective method for constructing large-scale 3D terrain model in network environment.

Land subsidence in urban area is becoming a severe geological hazard disturbing the urban construction and development. Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique has demonstrated a good capability of monitoring the large scale land deformation. High resolution and short wave radar data can help to improve the precision of deformation detection based on PSInSAR. In this paper, 15 scenes of TerraSAR-X SAR data are used to derive the estimation of the subsidence rate in the Wuqing district, Tianjin city in China. The combination of TIN and nearest-connection method (NCM) are first used to establish the differential network model. The results show that high resolution TX image can dramatically increase the valid PSs and improve investigation reliability, especially in linear man-made constructs.

The study focus on the process of metal electroplating on copper substrate to assemble LED chips and molding PET-copper foil to implement a flexible module with LED chips. The process can be divided into two parts,-assembling process and molding process. The LEDs are integrated on copper foil which can deal with the heat dissipation problem effectively. The metal electroplating on copper circuitry can achieve a soldered bonding to LED chips. The flexible layers of polyethylene terephthalate (PET)-copper foil are formed by two approaches-hot lamination and transfer molding. The thickness of PET-copper foil is an important parameter to the thermal design. A finite model is developed to study the effects of heat dissipation at different thickness of PET-copper foils. The results show that the flexible have a good thermal property with the thickness of PET-copper foil from 450um to 650um. Finally, a flexible model is simulated at temperature distribution with 5× 5 LEDs.

STUDY DESIGN Observational cross-sectional study. OBJECTIVE To perform a psychometric evaluation of Simplified Chinese versions of back pain beliefs questionnaires for use in health care professionals living in mainland China. SUMMARY OF BACKGROUND DATA Back pain beliefs are of importance in the development of chronic low back pain (LBP) and disability. Different types of beliefs exist with regard to LBP and these include inevitable consequences of LBP and fear-avoidance beliefs. LBP beliefs held by health care providers are also known to influence their patients' pain beliefs and can contribute to the development of chronic LBP and disability. At present, validated questionnaires such as the Back Beliefs Questionnaire, Health Care Providers' Pain and Impairment Relationship Scale, and Fear-Avoidance Beliefs Questionnaire are commonly used to investigate back pain beliefs held by health care professionals working in western countries. There are no published nor validated Simplified Chinese versions to allow investigation of back pain beliefs in health care professionals living in mainland China. METHODS The English versions of the earlier mentioned questionnaires were translated and culturally adapted into Simplified Chinese using the double-back-translation method. A psychometric evaluation of the translated questionnaires was conducted on 65 health care professionals (rehabilitation medicine specialists, osteopaths, and nurses), with and without LBP, practicing in Shanghai, China. The questionnaires were completed twice within 7- to 10-day period. RESULTS The Back Beliefs Questionnaire, Health Care Providers' Pain and Impairment Relationship Scale, and Fear-Avoidance Beliefs Questionnaire (work and physical subscales) had acceptable internal consistency (Cronbach α range: 0.70-0.87) and construct validity (r = 0.40-0.49, P < 0.05), good reproducibility (Intraclass correlation coefficients, ICC(2,1) range: 0.85-0.93) and an absence of any floor or ceiling effects. CONCLUSION This study showed that the Simplified Chinese versions of back pain beliefs questionnaires are valid and reliable. Therefore, these questionnaires can be used in research involving Chinese health care professionals living in mainland China.