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Increasing the number of satellites in a global navigation satellite system (GNSS) improves the positioning accuracy and increases availability. However, it reduces the positioning accuracy improvement rate and increases the calculation loads, which can cause battery usage problems in mobile devices using a GNSS. An appropriate satellite selection method is required. One current method entails the use of ideal satellite placement with respect to the minimum geometric dilution of precision (GDOP). In this study, the described ideal satellite placement with the minimum GDOP were divided in terms of the horizontal dilution of precision (HDOP) and vertical dilution of precision (VDOP). HDOP and VDOP were mathematically derived and analyzed. The derived formula was verified using simulations. The analysis was performed with actual dual GNSS satellite data. The satellites adjacent to the ideal placement were selected and the DOP was calculated. Simply selecting satellites closest to the ideal placement afforded large values for HDOP and VDOP. This issue was addressed using a satellite changing algorithm considering the dual GNSS, resulting in reduced values of the HDOP and VDOP.

At present, Global Navigation Satellite System (GNSS) satellites operate in medium Earth orbits (MEOs), geostationary orbits (GEOs), or inclined geosynchronous orbits (IGSOs). The QZSS consists of GEO and IGSO satellites. When we considering the QZSS skyplot in Japan and its surrounding areas, there are no satellites in the northern sky. This results in a geometric placement imbalance, and thereby, causes position errors. The fundamental method to solve this problem is to position a satellite in the vacant northern area. Therefore, in this research, the addition of navigation satellites with a highinclination, high-eccentricity orbit (a new type of orbit) is proposed. The vacant northern area can be filled effectively by adding a satellite using this orbit. Three satellites with this orbit were added to the QZSS in a simulation. Thereby, satellites were positioned effectively in the vacant northern area of the skyplot for Tokyo and Seoul. In addition, the improvement in performance was verified quantitatively through Horizontal Dilution of Precision (HDOP) and Vertical Dilution of Precision (VDOP). Accordingly, the addition of a satellite with a high-inclination, high-eccentricity orbit to the QZSS would enable more accurate positioning in Japan and its surrounding areas. [ABSTRACT FROM AUTHOR]

Background: In high income countries struggling with escalating health care costs and persistent lack of equity, there is growing interest in searching for innovative solutions developed outside national borders, particularly in low- and middle-income countries (LMICs). Engaging with global ideas to apply them to local health equity challenges is becoming increasingly recognized as an approach to shift the health equity landscape in the United States (US) in a significant way. No single name or set of practices yet defines the process of identifying LMIC interventions for adaptation; implementing interventions in high-income countries (HIC) settings; or evaluating the implementation of such projects. Objectives: This paper presents a review of the literature describing the practice of adapting global ideas for use in the US, particularly in the area of health equity. Specifically, the authors sought to examine; (i) the literature that advocates for, or describes, adaption of health-related innovations from LMICs to HICs, both generally and for health equity specifically, and (ii) implementation practices, strategies, and evidence-based outcomes in this field, generally and in the area of health equity specifically. The authors also propose terminology and a definition to describe the practice. Methods: The literature search included two main concepts: global learning and health equity (using these and related terms). The search consisted of text-words and database-specific terminology (e.g., MeSH, Emtree) using PubMed, Embase (Elsevier), CINAHL (Ebsco), and Scopus in March 2021. The authors also contacted relevant experts to identify grey literature. Identified sources were categorized according to theme to facilitate analysis. In addition, five key interviews with experts engaged with global ideas to promote health equity in the United States were conducted to develop additional data. Results: The literature review yielded over ninety (n = 92) sources relating to the adaptation of global ideas from low resource to higher resource settings to promote health equity (and related concepts). Identified sources range from those providing general commentaries about the value of seeking health-related innovations outside the US border to sources describing global projects implemented in the US, most without implementation or outcome measures. Other identified sources provide frameworks or guidance to help identify and/or implement global ideas in the US, and some describe the role of the World Health Organization and other international consortia in promoting a global approach to solving domestic health equity and related challenges. Conclusions: The literature review demonstrates that there are resources and commentary describing potential benefits of identifying and adapting novel global ideas to address health equity in the US, but there is a dearth of implementation and evaluation data. Terminology is required to define and frame the field. Additional research, particularly in the area of implementation science and evidence-based frameworks to support the practice of what we define as ‘global learning’ for health equity, is necessary to advance the practice.

Background: In India, most physicians pursue a specialist's degree resulting in a dearth of general practitioners (GPs). To provide primary care across populations and support universal healthcare coverage (UHC), there is a need to develop a core educational foundation for generalists and family medicine in undergraduate and post-graduate training. Methodology: A cross-sectional survey was conducted as a part of a medical educational needs assessment (ENA) with a focus on family medicine. Respondents included practicing physicians, residents and medical students in Himachal Pradesh, Delhi and Tamil Nadu. Descriptive and bi-variate data analysis (Pearson's Chi square, independent t-tests and analysis of variance [ANOVA]) was performed to summarise data and determine significant differences between demographic groups of respondents. Results: Three hundred and sixty-one surveys were completed. From which, 80.7% (284) of respondents felt that family medicine would be beneficial/very beneficial to the Indian health system. Respondents were split over whether family medicine programmes should be integrated within the existing bachelor of medicine and bachelor of surgery (MBBS) programmes (149/42.5%) or created as a separate post-graduate level specialty (131/37.3%). Overall, 84.2% (292) and 85.4% (294) agreed/strongly agreed that family medicine would benefit specialists and decrease the health disparities. Challenges include lack of information about family medicine and patients' use of specialists for primary healthcare needs. Conclusions: There was a positive response to expanding education for generalists and development of family medicine as a specialty in India. Mechanisms to support policies and programmes need to be further explored to ensure successful implementation across the country. Interest in skills-based courses can be an opportunity to provide GP and family medicine training while broader system-level changes are considered.