The national benchmarks on islands were mostly established by trigonometric leveling in Korea. This method results in inaccuracy, which is a serious problem in Geoga Grand Bridge construction work that tried to link t...The national benchmarks on islands were mostly established by trigonometric leveling in Korea. This method results in inaccuracy, which is a serious problem in Geoga Grand Bridge construction work that tried to link the mainland and the islands. The Geoga Grand Bridge （Pusan-Geoje fixed link project） was selected as the study area, a huge construction work in Korea that will connect the mainland （Pnsan） and an island （Gecje island）. However, the orthometric heights issued at benchmarks （JINH and GOFJ） were not consistent, because they did not refer to the same zero point, which would make the linking of the sections problematic. This paper introduces the precise local geoidas a vertical datum for the construction area in order to establish a consistent height system. To determine the precise local geoid for the construction area, we firstly developed a precise gravimetric geoid for Korea and its adjoining seas as a whole. This gravimetric geoid was developed by use of all available gravity data, including surface and satellite data on land and on the ocean. The gravimetrie gecid was computed by spherical fast fourier transform with modified Stokes＇ kernels. The remove-restore technique was used to eliminate the terrain effects by use of the RTM reduction and to determine the residual geoid by combining the GGM02S/EGM96 geopotential model, free-air gravity anomalies and high-resolutinn DEM data. Finally, the gravimetric model was fitted to the geoid heights obtained from GPS and tide observations （Ncps/Tiae） by least square coUocatian, to provide the final GPS-consistent local precise geoid model. The post-fit error （std. dev. ） of the final geoid to the NetS/Tide derived from GPS and tide observations was ± 2.2 cm for the construction area. We solved the height inconsistency problem by calculating the orthometric height of the benchmarks and the cnntrol points using the final geoid model. Also, the highly accurate orthometric height was estimated through the GPS/leveling technique by applying the developed local precise geoid. Therefore, the precise local geoid is expected to improve the quality of the construction procedure of the Geoga Grand Bridge.展开更多
Introduction: Study compare spinal anesthesia using hyperbaric bupivacine (0.5% - 0.75%) between fixed dose and height adjusted dose during elective cesarean section. Methods: Hundred parturients who had given their c...Introduction: Study compare spinal anesthesia using hyperbaric bupivacine (0.5% - 0.75%) between fixed dose and height adjusted dose during elective cesarean section. Methods: Hundred parturients who had given their consent and were scheduled for elective cesarean section under spinal anesthesia, were divided into four groups—first group received 0.5% hyperbaric bupivacine fixed dose, the second group received 0.5% hyperbaric bupivacine in a dose adjusted to the height, the third received 0.75% hyperbaric bupivacine fixed dose, the fourth group received 0.75% hyperbaric bupivacine in a dose adjusted to height. The anesthesia onset time, haemodynamic changes, side effects and fetal outcome observed. Results: Spinal block provide excellent surgical anesthesia in all patients. Anesthesia onset time is longer in adjusted than fixed groups, in 0.5% (5 ± 0.816 vs. 3.84 ± 0.746) (P Conclusion: Adjusting dose of hyperbaric bupivacine (0.5% - 0.75%) to patient’s height, decreases the dose of bupivacine in use, it also provide adequate anesthesia for elective cesarean section with decrease the use of vasopressors, the incidence and severity of maternal hypotention also markedly reduced.展开更多
文摘The national benchmarks on islands were mostly established by trigonometric leveling in Korea. This method results in inaccuracy, which is a serious problem in Geoga Grand Bridge construction work that tried to link the mainland and the islands. The Geoga Grand Bridge （Pusan-Geoje fixed link project） was selected as the study area, a huge construction work in Korea that will connect the mainland （Pnsan） and an island （Gecje island）. However, the orthometric heights issued at benchmarks （JINH and GOFJ） were not consistent, because they did not refer to the same zero point, which would make the linking of the sections problematic. This paper introduces the precise local geoidas a vertical datum for the construction area in order to establish a consistent height system. To determine the precise local geoid for the construction area, we firstly developed a precise gravimetric geoid for Korea and its adjoining seas as a whole. This gravimetric geoid was developed by use of all available gravity data, including surface and satellite data on land and on the ocean. The gravimetrie gecid was computed by spherical fast fourier transform with modified Stokes＇ kernels. The remove-restore technique was used to eliminate the terrain effects by use of the RTM reduction and to determine the residual geoid by combining the GGM02S/EGM96 geopotential model, free-air gravity anomalies and high-resolutinn DEM data. Finally, the gravimetric model was fitted to the geoid heights obtained from GPS and tide observations （Ncps/Tiae） by least square coUocatian, to provide the final GPS-consistent local precise geoid model. The post-fit error （std. dev. ） of the final geoid to the NetS/Tide derived from GPS and tide observations was ± 2.2 cm for the construction area. We solved the height inconsistency problem by calculating the orthometric height of the benchmarks and the cnntrol points using the final geoid model. Also, the highly accurate orthometric height was estimated through the GPS/leveling technique by applying the developed local precise geoid. Therefore, the precise local geoid is expected to improve the quality of the construction procedure of the Geoga Grand Bridge.
文摘Introduction: Study compare spinal anesthesia using hyperbaric bupivacine (0.5% - 0.75%) between fixed dose and height adjusted dose during elective cesarean section. Methods: Hundred parturients who had given their consent and were scheduled for elective cesarean section under spinal anesthesia, were divided into four groups—first group received 0.5% hyperbaric bupivacine fixed dose, the second group received 0.5% hyperbaric bupivacine in a dose adjusted to the height, the third received 0.75% hyperbaric bupivacine fixed dose, the fourth group received 0.75% hyperbaric bupivacine in a dose adjusted to height. The anesthesia onset time, haemodynamic changes, side effects and fetal outcome observed. Results: Spinal block provide excellent surgical anesthesia in all patients. Anesthesia onset time is longer in adjusted than fixed groups, in 0.5% (5 ± 0.816 vs. 3.84 ± 0.746) (P Conclusion: Adjusting dose of hyperbaric bupivacine (0.5% - 0.75%) to patient’s height, decreases the dose of bupivacine in use, it also provide adequate anesthesia for elective cesarean section with decrease the use of vasopressors, the incidence and severity of maternal hypotention also markedly reduced.
