Effects of Surveying Methods between GNSS and Direct Leveling on Elevation Values over Long Distance in Mountainous Area

• KUBODERA TAKAHIKO

  Faculty of Science and Engineering, Toyo University

• OKAZAWA HIROMU

  Faculty of Regional Environment Science, Tokyo University of Agriculture

• HOSOKAWA YOSHIHARU

  Emeritus Professor, University of Miyazaki

• KAWANA FUTOSHI

  Faculty of Regional Environment Science, Tokyo University of Agriculture

• MATSUO EIJI

  Faculty of Engineering, Kyushu Sangyo University

• MIHARA MACHITO

  Faculty of Regional Environment Science, Tokyo University of Agriculture

Abstract

Water use facilities such as irrigation and drainage channels, water gate, hydraulic drop etc. are constructed to make water supply to paddy field and upland field. In a planning of irrigation project, it is necessary to obtain elevation value with accuracy and efficiency around project site. In generally, elevation values are obtained by the direct leveling survey with specific instruments, e.g. digital or auto level, a couple of staffs and turning plates. The direct leveling survey also needs several benchmarks, which are points of reference with high accuracy location information including latitude, longitude and elevation. There is, however, a serious problem that survey work of the direct leveling survey must begin at several benchmarks. In the case of survey work in mountainous area, surveyors must carry out the direct leveling survey over several very-long routes, because there are few benchmarks. On the other hand, in the Global Navigation Satellite System (GNSS) surveying, elevation values can be obtained indirectly by observing carrier phase from multi positioning satellites such as GPS, GLONASS since 2011. This study started to install the new benchmark on a 920 m high mountain, about 5 km away from some known benchmarks in Karuizawa Town, Nagano Prefecture. After surveying the new benchmark by the GNSS and the direct leveling, we compared its elevation values. Furthermore, a streamlined survey process, the influence on most probable value and standard deviation by the difference of using satellite, “GPS-only” and “GPS and GLONASS” were investigated in the GNSS surveying. As the results, our tests found that dramatically streamlined survey process, “GPS-only” can obtain an elevation value that is consistent with the value from the direct leveling survey. Therefore, the GNSS surveying is useful to obtain accurate elevation values over long distance like very long channels.

Journal

• International Journal of Environmental and Rural Development

  International Journal of Environmental and Rural Development 7 (1), 62-69, 2016

  Institute of Environmental Rehabilitation and Conservation, Research Center

Keywords

• GPS
• GLONASS
• rigorous network adjustment
• observation duration

Details

• CRID: 1390282752370677248
• NII Article ID: 130007747576
• DOI: 10.32115/ijerd.7.1_62
• ISSN: 24333700
• ISSN: 2185159X
• Text Lang: ja
• Data Source:
  • JaLC
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed