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The thermal variation of long-distance heat transfer oil pipeline directly determines the gathering and transportation heat consumption. Accurate calculation of temperature variation along the route is the key to energy conservation and consumption reduction. In this paper, a mathematical model of thermal calculation for steady-state operation is established for different buried modes of long-distance transport pipelines, and the calculation method of soil temperature field and total heat transfer coefficient is given. The numerical solution is carried out by using the finite difference method. The test loop of gathering and transport operation was set up, and the steady-state operation test was carried out to verify the correctness of the model and the solution method.

The objective of this study was to examine the association between patient satisfaction with community health service (CHS) and self-management behaviors in patients with type 2 diabetes mellitus (T2DM). In all, 1691 patients with T2DM from 8 community health centers in 5 provinces in China participated in the present study. The dependent variables included 4 measures of self-management behaviors: regular self-monitoring of blood glucose (SMBG), prescribed medication adherence, recommended dietary changes, and regular exercise. The independent variable was patient satisfaction with CHS. Multivariable logistic regression models were performed to examine the association between patient satisfaction with CHS and self-management behaviors. The mean satisfaction score in the participants was 3.14 (out of a maximum of 5). After adjusting for covariates including demographic factors, health status, health knowledge, and socioeconomic status (SES), diabetic patients with high CHS satisfaction had better medication adherence (odds ratio [OR] 1.25, 95% confidence interval [CI] 1.02–1.55), increased exercise management (OR 1.19, 95% CI 1.06–1.35), and more SMBG (OR 1.16, 95% CI 1.03–1.32); all these associations varied across SES groups. The association between satisfaction and medication adherence was significant among participants younger than 65 years with lower education (OR 2.15, 95% CI 1.37–3.37), income (OR 1.62, 95% CI 1.13–2.32), and lower-status occupations (OR 1.69, 95% CI 1.16–2.47). Among participants younger than 65 years and had lower education attainment, the association between satisfaction and diet management was observed. There were positive associations between satisfaction and regular exercise among subgroups of participants younger than 65 years, except for lower education group. A significant association between satisfaction and SMBG among participants ≥65 years old, who also had lower SES and higher-status occupations, was also observed. The study findings suggested that T2DM patient satisfaction with CHS was moderate. High satisfaction with CHS indicated better medication adherence, exercise management, and SMBG, and these associations varied by SES.

Numerical simulations for penetration into C35 concrete by 27 kinds of shaped charges with different cone angles, different liner thicknesses at different stand-offs were performed based on AUTODYN-2D software in this paper. Titanium alloy with a density of 6.0g/cm3 was chosen as liner material. The formations of shaped charge jets (SCJs) were studied and the influence rules of liner thickness, cone angle and stand-off on penetration depth and borehole diameter of SCJs were analyzed. Predecessors’ theoretical research achievements were discussed. Results show that large liner thickness is unsuitable for small cone angle, which results in poor penetration efficiency. SCJ formed by larger cone angle and proper liner thickness is not very sensitive to stand-off distance, which has better penetration depth as well as borehole diameter. The penetration depth increases and crater diameter decreases along with the increasing of stand-off distance. These results show a great engineering significance.