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China's first Mars exploration mission, named Tianwen-1, landed on Mars on 15 May 2021. The Mars Surface Composition Detector (MarSCoDe) payload onboard the Zhurong rover applied the laser-induced breakdown spectroscopy (LIBS) technique to acquire chemical compositions of Martian rocks and soils. The quantitative interpretation of MarSCoDe-LIBS spectra needs to establish a LIBS spectral database that requires plenty of terrestrial geological standards. In this work, we selected 316 terrestrial standards including igneous rocks, sedimentary rocks, metamorphic rocks, and ores, whose chemical compositions, rock types, and chemical weathering characteristics were comparable to those of Martian materials from previous orbital and in situ detections. These rocks were crushed, ground, and sieved into powders less than <38 μm and pressed into pellets to minimize heterogeneity at the scale of laser spot. The chemical compositions of these standards were independently measured by X-ray fluorescence (XRF). Subsequently, the LIBS spectra of MAL standards were acquired using an established LIBS system at Shandong University (SDU-LIBS). In order to evaluate the performance of these standards in LIBS spectral interpretation, we established multivariate models using partial least squares (PLS) and least absolute shrinkage and selection (LASSO) algorithms to predict the abundance of major elements based on SDU-LIBS spectra. The root mean squared error (RMSE) values of these models are comparable to those of the published models for MarSCoDe, ChemCam, and SuperCam, suggesting these PLS and LASSO models work well. From our research, we can conclude that these 316 MAL targets are good candidates to acquire geochemistry information based on the LIBS technique. These targets could be regarded as geological standards to build a LIBS database using a prototype of MarSCoDe in the near future, which is critical to obtain accurate chemical compositions of Martian rocks and soils based on MarSCoDe-LIBS spectral data. [ABSTRACT FROM AUTHOR]

As a typical augmentation satellite system for centimeter-level positioning, PPP (Precise Point Positioning) service based on PPP-B2b signal of China's new generation BeiDou system (BDS-3) was released for Asia-Pacific area on July, 2020. This paper first introduces the recovery theory of PPP-B2b SSR (State Space Representation) messages and then implements a real-time PPP-B2b precise positioning terminal to decode and obtain the PPP-B2b SSR orbit, clock, and biases. On those bases, the coverage, signal-in-space, and positioning performance of PPP-B2b SSR are evaluated. The results show that PPP-B2b SSR of BDS-3 can cover the most area of 50°E-180°E, 30°S-70°N and improve signal-in-space accuracy significantly. The improvement rate on BDS clock offset can reach 77%, which far exceeds average 40% improvement on BDS orbit, while it is opposite for GPS with 80% improvement rate on orbit and 61% on clock offset. Average SISRE (signal-in-space range error) of PPP-B2b SSR is better than 10 cm. The 95% positioning results show that centimeter- to decimeter-level positioning can be achieved after a few minutes of convergence based on PPP-B2b SSR, which satisfies the BDS open service performance standard. Comparing to BDS PPP based on PPP-B2b SSR, BDS + GPS PPP can promote convergence significantly with average 40% improvement rate for 95% epochs and can further improve positioning accuracy with 30%-35% improvement rate in horizontal and 10%–15% in vertical direction. [ABSTRACT FROM AUTHOR]

Abstract: In sub-tropical city of Hong Kong where summer is hot and humid, the usage of outdoor spaces is often hindered due to thermal discomfort. In order to improve the thermal comfort of the outdoor environment and to make urban outdoor spaces delightful places for people to use and enjoy, better understanding of the thermal perception of people is needed. This paper presents the results of an outdoor thermal comfort study conducted in Hong Kong. The findings of the study reveal that air temperature, wind speed and solar radiation intensity are influential factors in determining the thermal sensation of people outdoor. Based on our analysis, the neutral physiological equivalent temperature (PET) in summer in Hong Kong is around 28°C. Under shaded condition, a wind speed of 0.9–1.3m/s is needed for a person in light clothing to achieve neutral thermal sensation in an urban environment. This understanding can contribute towards establishing wind performance standards for thermal comfort in hot and humid tropical and sub-tropical cities. [Copyright &y& Elsevier]

Purpose -- The purpose of this paper is to develop and test a model that identifies the impact of organizational justice on work performance. The model examined the mediating role played by organizational commitment and leader-member exchange (LMX) in linking organizational justice and work performance. Design/methodology/approach -- The data were collected from 793 completed questionnaires sampling employees from industries across the People's Republic of China. The questionnaire included scales to measure organizational justice, organizational commitment, LMX, and work performance. The measurement of constructs and the hypothesized relationships among variables were assessed by the use of structural equation modeling. The Baron and Kenny approach was used to test the mediating effects. Findings -- First, the relationship of organizational justice to work performance was mostly indirect, mediated by organizational commitment and LMX. Second, among the three kinds of organizational justice, interactional justice was the best predictor of performance. Lastly, organizational commitment accounted for more of the variance than LMX did in the mediating mechanism. Research limitations/implications -- The model developed in this article provides important insights in the study of the relationship between organizational justice and work performance. Future research needs to examine the model using a cross-national sample. Originality/value -- The link between organizational justice and work performance was mostly mediated by organizational commitment and LMX. [ABSTRACT FROM AUTHOR]

Background: China has had no effective and systematic information system to provide guidance for strengthening PHC (Primary Health Care) or account to citizens on progress. We report on the development of the China results-based Logic Model for Community Health Facilities and Stations (CHS) and a set of relevant PHC indicators intended to measure CHS priorities. Methods: We adapted the PHC Results Based Logic Model developed in Canada and current work conducted in the community health system in China to create the China CHS Logic Model framework. We used a staged approach by first constructing the framework and indicators and then validating their content through an interactive process involving policy analysis, critical review of relevant literature and multiple stakeholder consultation. Results: The China CHS Logic Model includes inputs, activities, outputs and outcomes with a total of 287 detailed performance indicators. In these indicators, 31 indicators measure inputs, 64 measure activities, 105 measure outputs, and 87 measure immediate (n = 65), intermediate (n = 15), or final (n = 7) outcomes. Conclusion: A Logic Model framework can be useful in planning, implementation, analysis and evaluation of PHC at a system and service level. The development and content validation of the China CHS Logic Model and subsequent indicators provides a means for stronger accountability and a clearer sense of overall direction and purpose needed to renew and strengthen the PHC system in China. Moreover, this work will be useful in moving towards developing a PHC information system and performance measurement across districts in urban China, and guiding the pursuit of quality in PHC. [ABSTRACT FROM AUTHOR]

Abstract: The current study examines how employees’ perceptions of empowerment impact the quality of the organization–employee relationship. Based on the on-line survey of 223 employees from a variety of companies in China, both dimensions of employee empowerment—feelings of competence and feelings of control—serve as positive predictors for organization–employee relationship. However, employees’ feelings of control wield more weight in the prediction than do feelings of competence. [Copyright &y& Elsevier]

In analyses of urban environments, city-level sustainability assessments standards have received a lot of attention. Many countries, particularly in the developed world, have developed the standards to measure the performance of neighborhoods, districts, and cities in achieving sustainable development goals. In this study, four standards from China and the United States were selected and analyzed within the scope of green and sustainable development. China's new Assessment Standard for Green Eco-districts (ASGE) targets to support China's New-type Urbanization Plan from the conceptual stage to the concrete implementation. LEED® rating systems are one of the important references for the development of ASGE. By comparing ASGE with the advanced standards it draws from, this study aimed to evaluate ASGE's work in adapting to China's national conditions; pointing out the strengths and weaknesses and proposing improvements. The study results indicate that the rating systems of ASGE are in line with China's national conditions, and that some non-technical indicators are forward-looking, but that there is still room for improvement in terms of implementation paths, weight assignment, number of indicators, and index system. Based on these explorations, this study provides suggestions for aspects of principles and methods that could be used for the construction of similar standards in developing countries. [ABSTRACT FROM AUTHOR]

• Variable speed units provide cost-effective solution to improve efficiency. • Fixed speed units are not economically competitive at higher efficiency ratings. • New standard brings accumulative CO 2 reductions of 12.8% between 2019 and 2050. • Accumulative bill saving is 2620 billion RMB between 2019 and 2050. • Continuous revision of the new standard could more than double the overall impact. China is the world's largest consumer of room air conditioners, and it contributes about a quarter of global space cooling CO 2 emissions. We model the costs and benefits of recently proposed new room air conditioner minimum energy performance standards (MEPS) in China. Our results suggest that newly proposed MEPS brings accumulative CO 2 emissions reductions of 12.8% between 2019 and 2050, and accumulative bill saving of 2620 billion RMB to China's consumers. The benefits of the proposed MEPS decrease with longer MEPS revision intervals and increase with shorter intervals—indicating that the intervals should be balanced to maximize benefits while accommodating constraints due to air conditioner manufacturer design cycles. We also model potential nationwide benefits from higher MEPS. Across two increasingly aggressive MEPS scenarios, China's room air conditioner electricity consumption and CO 2 emissions in 2050 are both reduced by 15–53% compared to the proposed MEPS. The highest-efficiency scenario (reaching MEPS of annual performance factor 5.4 in 2025) provides the largest long-term national benefits. These results could inform development of a Chinese regulatory regime that effectively updates room air conditioner MEPS. Because China is the world's largest manufacturer of room air conditioners, the economic, energy, and emissions benefits resulting from higher Chinese MEPS could also have a global reach. [ABSTRACT FROM AUTHOR]