2,032 research outputs found
Numerical investigation of particles turbulent dispersion in channel flow
This paper investigates the performance of Reynolds-averaged Navier-Stokes model on dispersion of particles in wall turbulence. A direct numerical simulation of wall-bounded channel flow with particles suspensions was set as a benchmark. The standard k-ω model coupled with two different eddy interaction models was used in Reynolds-averaged Navier-Stokes model and compared to the direct numerical simulation. Detailed comparisons between direct numerical simulation and Reynolds-averaged Navier-Stokes model on particle distribution evolving over time were carried out
Using inductive Energy Participation Ratio for Superconducting Quantum Chip Characterization
We have developed an inductive energy participation ratio (iEPR) method and a
concise procedure for superconducting quantum chip layout simulation and
verification that is increasingly indispensable in large-scale, fault-tolerant
quantum computing. It can be utilized to extract the characteristic parameters
and the bare Hamiltonian of the layout in an efficient way. In theory, iEPR
sheds light on the deep-seated relationship between energy distribution and
representation transformation. As a stirring application, we apply it to a
typical quantum chip layout, obtaining all the crucial characteristic
parameters in one step that would be extremely challenging through the existing
methods. Our work is expected to significantly improve the simulation and
verification techniques and takes an essential step toward quantum electronic
design automation
Pengaruh Penerapan Strategi Concept Mapping terhadap Hasil Belajar Siswa di Sekolah Dasar
This study aimed to analyze the influence of concept mapping strategy towards the learning result students in social science study on the V B grade of SD Negeri 17 Pontianak Kota. This study used an experimental method with Pre-Experimental design form using One-Group Pretest-Posttest Design. The population in this research were 68 students. The samples in this research was V B as a research class. Based on the t-test, the calculation result obtained t test (7,29) > t table (1,699) with significance level α = 5% means a significant influence using concept mapping strategy. The value of effect size (ES) is 0.39 with moderate category. It means that concept mapping strategy give a moderate effect to the learning result students in social science study on the V B grade of SD Negeri 17 Pontianak Kota
Does carbon dioxide pneumoperitoneum enhance wound metastases following laparoscopic abdominal tumor surgery? A meta-analysis of 20 randomized control studies
The mechanisms involved in the development of wound metastasis following laparoscopic abdominal tumor surgery remain unclear. The aim of this study was to accurately assess whether the duration of carbon dioxide pneumoperitoneum (CDP) during laparoscopic abdominal tumor surgery enhances wound metastases. We conducted a systematic review of PubMed, Cochrane Library, and Embase through December 2013 to identify animal experiments comparing wound recurrence between laparoscopic and gasless laparoscopic procedures or open procedures. The outcome of interest was the number of animals with a wound tumor. Meta-regression was used to assess whether heterogeneity was explained by study level covariates (animal model, study size, CDP pressure, duration, and evaluated time). Twenty randomized control studies involving 1,229 animals were included. Wound recurrence was not significant in the laparoscopic surgery (LP) vs. gasless laparoscopic surgery (GLP) subgroups [odds ratio (OR), 2.23; 95 % confidence interval (CI), 0.90–5.55; P = 0.08) or the LP vs. laparotomy (LA) subgroups (OR, 0.97; 95 % CI, 0.31–3.00; P = 0.08). Overall postoperative wound recurrence results were not significantly different between the study groups and controls (OR, 1.47; 95 % CI, 0.74–2.92; P = 0.28). A meta-regression analysis showed that the outcome was not correlated with the covariates (animal model: P = 0.82; evaluated time: P = 0.30; pressure of CDP: P = 0.12; duration time: P = 0.80). Current evidence suggests that CDP does not enhance wound metastases following laparoscopic abdominal tumor surgery. Additional large sample, well-designed, randomized, controlled trials are needed to further confirm whether CDP duration in laparoscopic abdominal tumor surgery significantly enhances wound recurrence
Study of an Energetic-oxidant Co-crystal: Preparation, Characterisation, and Crystallisation Mechanism
An energetic co-crystal consisting of the most promising military explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and the most well-known oxidant applied in propellants ammonium perchlorate has been prepared with a simple solvent evaporation method. Scanning electron microscopy revealed that the morphology of co-crystal differs greatly from each component. The X-ray diffraction spectrum, FTIR, Raman spectra, and differential scanning calorimetry characterisation further prove the formation of the co-crystal. The result of determination of hygroscopic rate indicated the hygroscopicity was effectively reduced. At last, the crystallisation mechanism has been discussed
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