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Global Navigation Satellite System (GNSS) network analysis benefits from precise point positioning with undifferenced (UD) or double differenced (DD) integer ambiguity resolution (IAR). Position time series with UD-IAR and a practical DD-IAR are compared for a mixture network consisting of 57 global and 82 regional stations with 4-year observations. The sparse global stations are more affected by different IAR methods than the regional stations of Crustal Movement Observation Network of China (CMONOC). The most significant differences between UD-IAR and the practical DD-IAR are observed in velocity estimations, with averages of 0.15 and 0.30 mm/yr for the horizontal and vertical components, respectively. UD-IAR can achieve smaller root mean square at 70–83 % of the daily solutions than the practical DD-IAR for global stations. Nevertheless, moderate differences of frame parameters and annual variations are introduced by different IAR methods. The IAR is also proved to be one of the potential origins for Global Positioning System (GPS) draconitic signals and white noise at high frequency. [ABSTRACT FROM AUTHOR]

Background: The manifestations of Polycystic Ovary Syndrome (PCOS), including acne, hirsutism, obesity, uncertain fertility, etc., can make women anxious, worried, or even depressed with their appearance and body. However, little relevant research has been conducted in the Chinese context. This mixed-method study aimed to understand how women with PCOS in China perceive their bodies and to examine the association between body image and depression.Methods: First, 101 PCOS patients participated in a survey using the Body Surveillance subscale of the Objectified Body Consciousness Scale, the Short-form Mishel Uncertainty in Illness Scale, the Appearance Anxiety Scale, and the Beck Depression Inventory-II, which measured participants' self-objectification, illness ambiguity, appearance anxiety, and depression, respectively. Second, fifteen women joined face-to-face semi-structured in-depth interviews, investigating their illness ambiguity, objectified experience, and behaviors to pursue beauty.Results: Results indicated a high level of self-objectification, illness ambiguity, appearance anxiety, and depression among women with PCOS in China and supported the significant associations among the outcomes. Qualitative findings presented a body image of the precarious body, indiscernible identity, and distraught mind.Limitations: A convenient sampling method was used. The generalization of the study results needs further validation. Future longitudinal studies are necessary to clarify the causal relationships among outcomes.Conclusions: This study presented women's body image with PCOS and found the negative impact of body image on their depression levels. This study was of both theoretical and practical significance. Appropriate mind-body therapies were suggested for them. [ABSTRACT FROM AUTHOR]

Obtaining reliable GNSS uncalibrated phase delay (UPD) or integer clock products is the key to achieving ambiguity-fixed solutions for real-time (RT) precise point positioning (PPP) users. However, due to the influence of RT orbit errors, the quality of UPD/integer clock products estimated with a globally distributed GNSS network is difficult to ensure, thereby affecting the ambiguity resolution (AR) performance of RT-PPP. In this contribution, by fully utilising the consistency of orbital errors in regional GNSS network coverage areas, a method is proposed for estimating regional integer clock products to compensate for RT orbit errors. Based on Centre National d'Études Spatiales (CNES) RT precise products, the regional GPS/BDS integer clock was estimated with a CORS network in the west of China. Results showed that the difference between the estimated regional and CNES global integer clock/bias products was generally less than 5 cm for GPS, whereas clock differences of greater than 10 cm were observed for BDS due to the large RT orbit error. Compared with PPP using global integer clock/bias products, the AR performance of PPP using the regional integer clock was obviously improved for four rover stations. For single GPS, the horizontal and vertical accuracies of ambiguity-fixed PPP solutions were improved by 56.2% and 45.3% on average, respectively, whereas improvements of 67.5% and 50.5% in the horizontal and vertical directions, respectively, were observed for the combined GPS/BDS situation. Based on a regional integer clock, the RMS error of a kinematic ambiguity-fixed PPP solution in the horizontal direction could reach 0.5 cm. In terms of initialisation time, the average time to first fix (TTFF) in combined GPS/BDS PPP was shortened from 18.2 min to 12.7 min. In view of the high AR performance realised with the use of regional integer clocks, this method can be applied to scenarios that require high positioning accuracy, such as deformation monitoring. [ABSTRACT FROM AUTHOR]

The quality and availability of Uncalibrated Phase Delay (UPD) solutions are crucial to the Precise Point Positioning (PPP) service, and the long-term temporal variability and its contributing factors should be better understood. In this paper, we comprehensively investigate the long-term time-varying characteristics of each UPD product respectively generated by a global and regional network and their interoperable application in PPP-AR (ambiguity resolution), the sampling of the WL and NL UPDs are daily and 30 s, respectively. Firstly, in terms of our 30 day Wide-Lane (WL) UPD products of 31 satellites, the Standard Deviation (STD) of each satellite WL UPDs ranges from 0.04 to 0.06 cycles, indicating that the long-term prediction accuracy of satellite WL UPD is sufficient for fixing Wide-Lane ambiguities. Secondly, when a satellite in eclipsing the discontinulity may corrupt the determination of Narrow-Lane (NL) UPD in form of offset, as a result of lacking or poor satellite attitude dynamic modeling. When the influence of discontinuity is removed, the STD of our estimated satellite NL UPDs is less than 0.05 cycles. Thirdly, the STD of our estimated receiver WL UPDs is mainly below 0.2 cycles, which implies that its stability is one order poorer that of the satellite. In addition, if they are used for stations in and around the network covered region, the stability of the UPD products from the CMONOC (Crustal Movement Observation Network of China) is better than that from a global network, benefit from the fact that all the CMONOC stations are equipped with the same receiver type. Finally, the PPP-AR results show that a rate of 82.9% for stations with a WL-ambiguity-fixed rate of over 90% while 69.5% for stations with an NL-ambiguity-fixed rate of over 80% can be achieved when using UPD from the global network, which is worse than that of using UPD from the CMONOC (85.7% for stations with a WL-ambiguity-fixed rate of over 90% while 75% for stations with an NL-ambiguity-fixed rate of over 80%). The results of the experiment on the UPD interoperable application in PPP show that the global network UPD products can provide a fast AR at any single station, and the convergence time is well below 25 min. Particularly, when the location of a station is in and around the regional network, our results show that the PPP results obtained using regional UPDs enable the consistent use of global UPDs. When the location of a station is far away from the regional network, using the regional UPDs can not achieve PPP-AR. Finally, the WL UPDs of the previous day is used for forecasting to estimate the NL UPDs, the stability analysis results of NL UPDs solution and positioning results are demonstrate the validity of forecasted UPD products. [ABSTRACT FROM AUTHOR]

We report data from the first incentivized artefactual field experiment conducted in China to understand whether Chinese migrants differ from non-migrants in terms of preferences regarding risk and uncertainty in various contexts. We find that, compared to non-migrants, migrants are significantly more likely to enter competitions when they expect competitive entries from others; however, migrants are not different from non-migrants in risk and ambiguity preferences where strategic uncertainty is absent. Our results suggest that migration may be driven more by a stronger belief in one’s chance of succeeding in an uncertain competitive environment than by differences risk attitudes related to state uncertainty. [ABSTRACT FROM AUTHOR]

Yongren Lolo (as well as a portion of related Tibeto-Burman languages) exhibits a type of DOM in a wide range of clause types strictly based on ambiguity. Devices such as morphological case-marking and word order fixations are taken out of the toolbox only if the assignment of semantic roles is not implied by the semantics of the predicate and its arguments. ADDOM-languages (Ambiguity-Driven Differential Object Marking languages) such as Yongren Lolo resist any rigid alignment pattern of semantic roles. Earlier attempts by linguists to sketch Lolo-style syntax in terms of the grammatical relations of primary object and ‘anti-ergative’ marking are shown to fail for various reasons. The characteristic feature of ADDOM-languages seems to be their ability to strike a special deal between two conflicting constraints that operate at a deeper level of syntactic organization: Economy and Markedness. Based on the interplay of these constraints, I define a wide range of theoretic ADDOM-structures and position Yongren Lolo within this typology. [Copyright &y& Elsevier]