For the two newly launched satellites(PRN number 27 and 28) of the future global BeiDou navigation satellite system(BDS-3), there is no available broadcast ephemeris data and other initial orbit information, but the i...For the two newly launched satellites(PRN number 27 and 28) of the future global BeiDou navigation satellite system(BDS-3), there is no available broadcast ephemeris data and other initial orbit information, but the initial orbit is the fundamental of the comprehensive analysis of the satellites and their signals. Precise orbit determination(POD) also requires determination of a priori initial value with a certain precision in order to avoid problems such as filter divergence during POD. Compared with the Newton iteration method, which relies on the initial value, this study utilizes the Bancroft algorithm to directly solve the nonlinear equations with the advantage of numerical stability. The initial orbits of these two satellites are calculated based on new code signals, and their results are analyzed and discussed. The experimental results show that, with the exception of very few epochs, when the new code signal is utilized, the median and robust variance factor of the observed residuals computed using pseudo-range observations and the solved initial orbits are less than 4 and 2 m, respectively. It also shows that this solution can be used for rapid initial orbit recovery after maneuvers of the new BeiDou satellites.展开更多
With the development of socialism market economy, the former Bar Code ForCommodity Management Measures (being called Old Measures for short hereafter) issued by the NationalBureau of Quality and Technical Supervision ...With the development of socialism market economy, the former Bar Code ForCommodity Management Measures (being called Old Measures for short hereafter) issued by the NationalBureau of Quality and Technical Supervision can not adapt to the requirement of managing for barcode for commodity. Therefore, for the purpose of standardize bar code for commodity managementstandard, ensuring its quality, speeding up the application of it in electronic business andcirculating field and accelerating the course of being a well informed country, a new Bar Code ForCommodity Management Measures (New Measures for short) has been issued by the General Administratorof Quality Supervision, Inspection and Quarantine of P.R. China (AQSIQ) on May 30th, 2005, and putinto force in October, 2005. At the same time, the Old Measures issued on July 3rd, 1998 has beenabolished.展开更多
The present paper seeks to shed light on the main factors lying behind the non-implementation of Article 20 of the New Moroccan Family Law reformed in 2004 which is concerned with legal minimum age of marriage for bot...The present paper seeks to shed light on the main factors lying behind the non-implementation of Article 20 of the New Moroccan Family Law reformed in 2004 which is concerned with legal minimum age of marriage for both sexes, 18 years old for both. This study aims at investigating why the number of marriages of young girls continue to increase despite the establishment of the Law. The author takes the region of Fez as a case in point to explore this social behavior in Moroccan society. A qualitative approach has been adopted by interviewing 10 persons including Family Affairs Judges, lawyers and University Professors of Islamic studies at the University of Fez. Added to this, the technique of observation has equally been utilized to have everyday life concrete experiences of young girls ＂marriages＂. It has been argued that a unilateral approach to this social phenomenon cannot succeed to understand the complex nature of this bad social habit that is still predominant among rural areas and marginalized urban districts. A rather global approach taking into account the economic, socio-cultural, and legal dimension of the issue under investigation proves to be much more adequate to explore the intricate nature of this problems in which a number of diverse variables interact. The paper ends up with a conclusion and a number of recommendations on how to reduce this social act.展开更多
The sUdeway design is the key in the design of the disc vibrating feeder. However, no reliable theoretical guidance has come into existence, which greatly restricted the application of CAD（ Computer-aided design）. I...The sUdeway design is the key in the design of the disc vibrating feeder. However, no reliable theoretical guidance has come into existence, which greatly restricted the application of CAD（ Computer-aided design）. In order to feed the application of CAD technology, we must make improvements to the existing coding method. Based on the similarity principle of Group Technology and existing coding system, a new coding method applicable to slide- way design is brought forward. The existing coding system could get optimized by means of analysing and studying the influence imposed by the parts＇ shape and posture features. More detailed information about the parts could be supplied by the new coding system, which makes the design simpler, more convenient and more accurate with the subjoin of the initial and targeted codes.展开更多
基金supported by the Collaborative Precision Positioning Project funded by the Ministry of Science and Technology of China (No.2016YFB0501900)China Natural Science Funds (No.41231064,41674022,41574015)
文摘For the two newly launched satellites(PRN number 27 and 28) of the future global BeiDou navigation satellite system(BDS-3), there is no available broadcast ephemeris data and other initial orbit information, but the initial orbit is the fundamental of the comprehensive analysis of the satellites and their signals. Precise orbit determination(POD) also requires determination of a priori initial value with a certain precision in order to avoid problems such as filter divergence during POD. Compared with the Newton iteration method, which relies on the initial value, this study utilizes the Bancroft algorithm to directly solve the nonlinear equations with the advantage of numerical stability. The initial orbits of these two satellites are calculated based on new code signals, and their results are analyzed and discussed. The experimental results show that, with the exception of very few epochs, when the new code signal is utilized, the median and robust variance factor of the observed residuals computed using pseudo-range observations and the solved initial orbits are less than 4 and 2 m, respectively. It also shows that this solution can be used for rapid initial orbit recovery after maneuvers of the new BeiDou satellites.
文摘With the development of socialism market economy, the former Bar Code ForCommodity Management Measures (being called Old Measures for short hereafter) issued by the NationalBureau of Quality and Technical Supervision can not adapt to the requirement of managing for barcode for commodity. Therefore, for the purpose of standardize bar code for commodity managementstandard, ensuring its quality, speeding up the application of it in electronic business andcirculating field and accelerating the course of being a well informed country, a new Bar Code ForCommodity Management Measures (New Measures for short) has been issued by the General Administratorof Quality Supervision, Inspection and Quarantine of P.R. China (AQSIQ) on May 30th, 2005, and putinto force in October, 2005. At the same time, the Old Measures issued on July 3rd, 1998 has beenabolished.
文摘The present paper seeks to shed light on the main factors lying behind the non-implementation of Article 20 of the New Moroccan Family Law reformed in 2004 which is concerned with legal minimum age of marriage for both sexes, 18 years old for both. This study aims at investigating why the number of marriages of young girls continue to increase despite the establishment of the Law. The author takes the region of Fez as a case in point to explore this social behavior in Moroccan society. A qualitative approach has been adopted by interviewing 10 persons including Family Affairs Judges, lawyers and University Professors of Islamic studies at the University of Fez. Added to this, the technique of observation has equally been utilized to have everyday life concrete experiences of young girls ＂marriages＂. It has been argued that a unilateral approach to this social phenomenon cannot succeed to understand the complex nature of this bad social habit that is still predominant among rural areas and marginalized urban districts. A rather global approach taking into account the economic, socio-cultural, and legal dimension of the issue under investigation proves to be much more adequate to explore the intricate nature of this problems in which a number of diverse variables interact. The paper ends up with a conclusion and a number of recommendations on how to reduce this social act.
文摘The sUdeway design is the key in the design of the disc vibrating feeder. However, no reliable theoretical guidance has come into existence, which greatly restricted the application of CAD（ Computer-aided design）. In order to feed the application of CAD technology, we must make improvements to the existing coding method. Based on the similarity principle of Group Technology and existing coding system, a new coding method applicable to slide- way design is brought forward. The existing coding system could get optimized by means of analysing and studying the influence imposed by the parts＇ shape and posture features. More detailed information about the parts could be supplied by the new coding system, which makes the design simpler, more convenient and more accurate with the subjoin of the initial and targeted codes.
