Pseudo-offset migration （POM） is a new method for prestack time migration of converted waves that improves on equivalent-offset migration （EOM）. The mapping of POM is different than EOM but the purpose of the two ...Pseudo-offset migration （POM） is a new method for prestack time migration of converted waves that improves on equivalent-offset migration （EOM）. The mapping of POM is different than EOM but the purpose of the two methods is to map the input samples to the common conversion scatter point （CCSP） gathers. This paper introduces the principles of the two migration methods and model parameter sensitivity tests for both POM and EOM. At large offset-to-depth ratios the hyperbolic approximation, the three-term approximation and the double square root （DSR） equation are used to NMO-correct the mapped POM gathers to obtain more accurate migration velocities. These equations were derived and calculated by small pseudo offset. POM is then used to image complex structure and prestack time migration.展开更多
An English-Chinese Dictionary （ 咭唎国译语, Ying Ji Li Guo Yi Yii） and A Portuguese-Chinese Dictionary （播时都噶礼雅话, Bo Lti Duo Ga Li Ya Hua） are reckoned as the coUative dictionaries compiled by the Office of ...An English-Chinese Dictionary （ 咭唎国译语, Ying Ji Li Guo Yi Yii） and A Portuguese-Chinese Dictionary （播时都噶礼雅话, Bo Lti Duo Ga Li Ya Hua） are reckoned as the coUative dictionaries compiled by the Office of Interpreters and Translators （会同四译馆, Hui Tong Si Yi Guan） in Qianlong time （1748）, Qing dynasty. There is only one original manuscript of these books gathered and preserved by the Palace Museum. In the present paper, we intent to introduce the significant value and detailed information of these two official collative dictionaries from social background, process of compilation, and stylistic basis of the book. Meanwhile, we will primarily work out the phonetic principles between Canton dialect and foreign languages also indicate the dialect characteristics after clarifying the faults and errors. The present paper may supply with a rudimentary knowing and resource to the realm of ＂Canton English＂ and ＂Canton Portuguese＂, even to the social status and Chinese dialect in Canton area for certain period. Detailed and specific research, especially for A Portuguese-Chinese Dictionary, still lies for future discovery.展开更多
In mountainous area, gravity survey external corrections, including terrain and Bouguer corrections, are the prerequisites for gravity data processing and interpretation. This paper presents a suite of techniques for ...In mountainous area, gravity survey external corrections, including terrain and Bouguer corrections, are the prerequisites for gravity data processing and interpretation. This paper presents a suite of techniques for spherical terrain and slab corrections for a finite spherical shell based on the analysis of conventional external corrections and deduces an equation for spherical terrain correction. The processing of gravity data acquired in the ZJJ area, South China shows that this technique significantly improves the accuracy of terrain corrections, and the quality of the data reaches or approaches the data acquired on plains.展开更多
An in situ calibration system is a versatile exploration instrument for electrochemical sensors investigating the biochemical properties of the marine environment. The purpose of this paper is to describe the design o...An in situ calibration system is a versatile exploration instrument for electrochemical sensors investigating the biochemical properties of the marine environment. The purpose of this paper is to describe the design of an auto-calibrating system for electrochemical (pH) sensors, which permits two-point in situ calibration, suitable for long-term measurement in deep sea aqueous environments. Holding multiple sensors, the instrument is designed to perform long-term measurements and in situ calibrations at abyssal depth (up to 4000 m). The instrument is composed of a compact fluid control system which is pressure-equilibrated and designed for deep-sea operation. In situ calibration capability plays a key role in the quality and reproducibility of the data. This paper focuses on methods for extending the lifetime of the instrument, considering the fluidics design, mechanical design, and low-power consumption of the electronics controller. The instrument can last 46 d under normal operating conditions, fulfilling the need for long-term operation. Data concerning pH measured during the KNOX18RR cruise (Mid-Atlantic Ridge, July-August, 2008) illustrate the desirable properties of the instrument. Combined with different electrodes (pH, H2, H2S, etc.), it should be of great utility for the study of deep ocean environments, including water column and diffuse-flow hydrothermal fluids.展开更多
基金This work is sponsored by the Nation's Key Scientific & Technologic Projects (2003 BA613-09).
文摘Pseudo-offset migration （POM） is a new method for prestack time migration of converted waves that improves on equivalent-offset migration （EOM）. The mapping of POM is different than EOM but the purpose of the two methods is to map the input samples to the common conversion scatter point （CCSP） gathers. This paper introduces the principles of the two migration methods and model parameter sensitivity tests for both POM and EOM. At large offset-to-depth ratios the hyperbolic approximation, the three-term approximation and the double square root （DSR） equation are used to NMO-correct the mapped POM gathers to obtain more accurate migration velocities. These equations were derived and calculated by small pseudo offset. POM is then used to image complex structure and prestack time migration.
文摘An English-Chinese Dictionary （ 咭唎国译语, Ying Ji Li Guo Yi Yii） and A Portuguese-Chinese Dictionary （播时都噶礼雅话, Bo Lti Duo Ga Li Ya Hua） are reckoned as the coUative dictionaries compiled by the Office of Interpreters and Translators （会同四译馆, Hui Tong Si Yi Guan） in Qianlong time （1748）, Qing dynasty. There is only one original manuscript of these books gathered and preserved by the Palace Museum. In the present paper, we intent to introduce the significant value and detailed information of these two official collative dictionaries from social background, process of compilation, and stylistic basis of the book. Meanwhile, we will primarily work out the phonetic principles between Canton dialect and foreign languages also indicate the dialect characteristics after clarifying the faults and errors. The present paper may supply with a rudimentary knowing and resource to the realm of ＂Canton English＂ and ＂Canton Portuguese＂, even to the social status and Chinese dialect in Canton area for certain period. Detailed and specific research, especially for A Portuguese-Chinese Dictionary, still lies for future discovery.
文摘In mountainous area, gravity survey external corrections, including terrain and Bouguer corrections, are the prerequisites for gravity data processing and interpretation. This paper presents a suite of techniques for spherical terrain and slab corrections for a finite spherical shell based on the analysis of conventional external corrections and deduces an equation for spherical terrain correction. The processing of gravity data acquired in the ZJJ area, South China shows that this technique significantly improves the accuracy of terrain corrections, and the quality of the data reaches or approaches the data acquired on plains.
基金Project supported by National Natural Science Foundation of China (No. 40637037)the National High-Tech Research and Development Program (863) of China (No. 2007AA091901)+1 种基金the National Science Foundation of U.S. (No. 0525907)the China Scholarship Council (No. 2009632124)
文摘An in situ calibration system is a versatile exploration instrument for electrochemical sensors investigating the biochemical properties of the marine environment. The purpose of this paper is to describe the design of an auto-calibrating system for electrochemical (pH) sensors, which permits two-point in situ calibration, suitable for long-term measurement in deep sea aqueous environments. Holding multiple sensors, the instrument is designed to perform long-term measurements and in situ calibrations at abyssal depth (up to 4000 m). The instrument is composed of a compact fluid control system which is pressure-equilibrated and designed for deep-sea operation. In situ calibration capability plays a key role in the quality and reproducibility of the data. This paper focuses on methods for extending the lifetime of the instrument, considering the fluidics design, mechanical design, and low-power consumption of the electronics controller. The instrument can last 46 d under normal operating conditions, fulfilling the need for long-term operation. Data concerning pH measured during the KNOX18RR cruise (Mid-Atlantic Ridge, July-August, 2008) illustrate the desirable properties of the instrument. Combined with different electrodes (pH, H2, H2S, etc.), it should be of great utility for the study of deep ocean environments, including water column and diffuse-flow hydrothermal fluids.
