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Background After being completely promoted for less than seven years, China's contracted family doctor service work still faces a number of development problems. The primary obstacle impeding the work of contracted family doctor service is an inadequate guarantee mechanism. There is an urgent need for scientific and reasonable policies on contracted family doctor service to guarantee the effective development of the work. Objective To quantitatively analyze the textual content of China's contracted family doctor service policies, to explore the focus and shortcomings of the existing policies, and to provide the basis and reference for the development and optimization of the subsequent contracted family doctor service policies. Methods Policy texts were collected by visiting the official websites of the China government and the National Health Commission of the People's Republic of China on 2023-01-10, and 15 policy texts on contracted family doctor service from 2015—2022 were selected to construct a three-dimensional analytical framework of policy tools-stakeholders-policy strength, to categorize, code, and analyze the policy documents. Results Supply-based, demand-based, and environment-based tools accounted for 30.5% (69/226), 19.0% (43/226), and 50.5% (114/226) of the policy tool dimension. Family doctors, contractors, non-contractors, primary medical and health care institutions, hospitals (secondary and above), and the government accounted for 29.2% (123/422), 14.7% (62/422), 9.2% (39/422), 21.3% (90/422), 13.3% (56/422), and 12.3% (52/422) of the stakeholder dimension. The average strength of China's contracted family doctor service policies was 2.2 points. In the cross-dimension of policy tools-stakeholders, the distribution of stakeholders in supply-based and environment-based tools was relatively poor. There were some sub-tools that were absent from the policy tools. In the cross-dimension of policy tools-policy strength, environment-oriented policy instruments were used more often as policy strength increased. In the cross-dimension of stakeholders-policy strength, there were large differences of the policy strength matching scores among various stakeholders. Family doctors had the highest score (311 points) with non-contractors the lowest score (90 points) . Conclusion From the perspective of policy tools, policy tools should be allocated rationally, with the weight of use continuously adjusted, the internal structure optimized, and the rationality of the distribution of policy tools among stakeholders improved. From the stakeholder's perspective, all stakeholders should be taken into account, their respective positions need to be clarified, and the demand of the non-contractors should be emphasized. From the perspective of policy strength, the policy supervision and management capacity ought to be strengthened to continuously improve the implementation of the policy of contracted family doctor service.

【Objective】 Uniformity coefficient is an important parameter in design and operation of sprinkler irrigation. Based on CU and DU, this paper proposed a methods to evaluate whole and local water distribution to help improve design of sprinkler systems and the rational configuration of operating parameters. 【Method】 We propose a uniformity coefficient DUl and DUh based on by defying positive and negative skewed distribution. Water distribution of the Nelson D3000 nozzle was measured and calculated, and the ability of DUl, DUh, CU and DU for evaluating water distribution, sensitivity to deficient or excessive irrigation, and uniformity under different nozzle-spacing and working pressure were compared and evaluated. 【Result】 When the irrigation occurs at 1.5R combined spacing, only DUh shows poor uniformity, where the positive deviation is concentrated in a small region. The sensitivity of CU and DUh was 11.15% and 9.32%, respectively. DUl and DUh were more sensitive to small area deficit irrigation, with sensitivity being 4.69% and 5.70%, respectively. The combined distance has significant influence on DUl, DUh, CU and DU. With the increase in working pressure, DUl and DUh showed significant differences, and the differences were more significant than CU and DU, with the F value being 0.123 and 0.399. DUl, DUh are more accurate. Based on CU level classification standard, the division standard of horizontal classification evaluation index with the dynamic change of uniformity coefficient DUl and DUh with positive and negative deviation distribution is constructed. Assuming an equal distribution of positive and negative deviations, the pass criteria for DUl and DUh are 70% and 130%, respectively. 【Conclusion】 DUl and DUh based on deviation distribution are superior to CU and DU for accurately evaluating water distribution uniformity and optimizing sprinkler configuration.

BackgroundThe use of controlled X-ray sources instead of 137Cs radioactive sources in density logging has become a new trend. The intensity of the X-ray source is substantially influenced by the high voltage on the target substrate, and the density measurement uncertainty can be maintained at 0.01 g·cm-3 when the high voltage is 350 kV.PurposeThis study aims to analyze the parameters of the shielding material and thickness suitable for the 350 kV high-voltage X-ray density logging instrument.MethodsThe Monte Carlo method was used to analyze the energy spectrum and counting rate of X-rays passing through different materials and thicknesses. By comparing the correlation between the 0~0.15 MeV and 0.15~0.35 MeV energy windows, the reasons for the difference between the X-ray attenuation and detector count rate in different energy windows were determined. In addition, combined with the actual instrument model construction of the four-detector X-ray density logging instrument, the influence of the three parts of particles on the detector was primarily considered. The placement mode and optimal thickness of each part of the shield for detectors were analyzed and designed using Monte Carlo N-particle (MCNP) simulation.ResultsThe simulation results show that the attenuation of X-rays in high- and low-energy windows increases with increase of atomic number and thickness of shielding materials. When tungsten nickel iron alloy is selected as the shielding material for the four-detector X-ray density logging instrument model, the suitable thickness of the shield between the base and the near-source detector is 1.75 cm. Meanwhile, to maintain the high voltage of X-ray generator at 350 kV, a shield layer with a thickness of 0.2 cm is placed between each detector, and a shield layer with a thickness of 0.35 cm is added to the back of the detector.ConclusionsThis study provides the design theory and key parameters for shielding materials and structures in the development of X-ray density logging tool.

【Objective】 Refractive sprinkler spray head mobile irrigation is a widely used irrigation system. In this paper, we proposed a model to calculate its water distribution and hydraulic characteristics for helping optimize its operating parameters and configuration. 【Method】 We used the sprinkler intensity equivalent stretching method and constructed a mobile sprinkler water distribution model based on the primary orthogonal polynomial fitting. The model was then applied to the R3000, S3000 and O3000 rotary refractive sprinkler head systems to analyze their water distribution under working pressure ranging from 50 to 150 kPa, moving speed from 20 to 45 m/h, sprinkler spacing from 1.2 to 8.4 m. 【Result】 ① The water depth of all three systems decreased with the increase in sprinkler distance. Compared with a fixed system, the three mobile systems increased spraying uniformity by 2.36% to 11.17%. ② With the increase in working pressure, the effective spraying radius of the R3000, S3000 and O3000 systems gradually increased, while their spraying uniformity increasing first followed by a fall. The average water depth and distribution uniformity of the mobile systems decreased with the increase in moving speed, albeit the change was small ranging from 0.59% to 1.38% for the three systems. With the increase in sprinkler distance, the average water depth and the spraying uniformity decreased in a fluctuating way. ③ Considering the influence of working pressure and sprinkler spacing, the R3000, S3000 and O3000 gave the highest spraying uniformity when the working pressure/distance was 150 kPa/3.6 m, 150 kPa/2.4 m and 130 kPa/3.6 m, respectively. 【Conclusion】 The equivalent stretching method reduces the number of fittings in model construction and improves modelling accuracy. Increasing working pressure or reducing sprinkler spacing can improve spraying uniformity.