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This review paper examines the topic of descriptive statistics, which is a study of statistics, deriving from basic mathematics. The paper discusses common descriptive statistics using a combination of numerical examples and graphical demonstrations. The paper introduces the definitions of some basic descriptive statistics and their corresponding formulas. The paper then reviews several research articles published in recent years in which researchers have used descriptive statistics to help analyze housing prices and the relationship between the stock market and trust. This review paper consults tables from other research articles with descriptive statistics and uses specific data to demonstrate how these statistics help researchers draw meaningful conclusions about the subjects of the analysis. The final conclusion is that although descriptive statistics is a simple method of summarizing data, it is fundamental and meaningful in statistical analysis and that can be used as a building block on which further analysis can be based.

Metalens has emerged as an important optical block in free-space optical systems, which shows excellent performance. Even the metalens based on gradient index (GRIN) profiles can be implemented for on-chip beam focusing behavior. However, for most previous schemes, the GRIN metalenses can only achieve on-chip beam focusing behavior in one dimension, which limits their applications in low-loss waveguide interconnecting or fiber-to-chip coupling. In this paper, an on-chip half Maxwell’s fisheye lens based on GRIN profiles with subwavelength features, integrated with silicon waveguides, is experimentally demonstrated. Benefitting from the index distribution and beam focusing characteristics of the half Maxwell’s fisheye lens, an on-chip beam transforming can be achieved for transverse electric (TE) fundamental mode in two waveguides with different heights and widths. The simulated 1 dB bandwidth can reach 1100 nm, which exhibits great prospects in integrated photonic circuits. The measured insertion loss of an on-chip 5.4 μm-length lens is less than 1 dB to connect a 220 nm-height, 8 μm-wide waveguide, and a 60 nm-height, 0.5 μm-wide waveguide in the wavelength range of 1280–1620 nm.

Purpose A common surgical methods for the treatment of coronary heart disease is coronary artery bypass grafting ( CABG ). The most important concern is the graft patency. When restenosis or occlusion occurs on the graft, the blood supply to the downstream will be reduced, and serious myocardial ischemia will occur again. Hemodynamics are the key factors affecting the graft patency. If the hemodynamic results of the graft under different surgical methods can be known before coronary artery bypass grafting, it can help doctors to choose the optimal operation method. Methods In this study, the modeling and simulation method of multi-scaled model of coronary had been designed. The 3D model of the bypass surgery region is constructed by the 3D reconstruction of the patient's medical imaging and the virtual bypass surgery. The individuation lumped parameter model is constructed by the basic physiological information of the patients. Finally, the two models are connected by a special boundary surface coupling algorithm to construct a 0D-3D coupled multi-scaled model that can be used to calculate the hemodynamic environment. Through calculation, the flow waveform, wall shear stress(WSS), oscillating shear index(OSI) and other hemodynamic parameters in the graft under different bypass methods were compared, and the optimal operation method with the best hemodynamic environment was selected. Results The method was used to calculate two clinical cases, and the effectiveness of the method was proved by the comparison of calculated graft flow and real graft flow, and the comparison of hemodynamic environment and graft outcomes after one year. Conclusion This method can realize preoperative evaluation of the hemodynamic environment of the graft under different bypass methods, and then select the optimal operation method for the patients and improve the graft patency after operation.

Aluminum nitride has advantages ranging from a large transparency window to its high thermal and chemical resistance, piezoelectric effect, electro-optic property, and compatibility with the complementary metal-oxide-semiconductor fabrication process. We propose a hybrid aluminum nitride and silicon platform for integrated photonics. Hybrid aluminum nitride–silicon basic photonic devices, including the multimode interferometer, Mach–Zehnder interferometer, and micro-ring resonator, are designed and fabricated. The measured extinction ratio is > 22 dB and the insertion loss is < 1 dB in a wavelength range of 40 nm for the Mach–Zehnder interferometer. The extinction ratio and intrinsic quality factor of the fabricated micro-ring resonator are > 16 dB and 43,300, respectively. The demonstrated hybrid integrated photonic platform is promising for realizing ultralow-power optical switching and electro-optic modulation based on the piezoelectric and electro-optic effects of aluminum nitride thin films.

Background: Different Traditional Chinese medicine (TCM) constitution types have different disease susceptibility and tendency, and TCM constitution identification is of great significance in TCM clinical practice. The TCM constitution identification method based on observation and consultation is subjective, and the objective identification technique opens up a new way to modernize TCM treatment. Our study aimed to build a TCM constitution identification model based on tongue feature data and machine learning algorithms, which provides a new fast and accurate method for TCM constitution identification.Methods: We use TFDA-1 tongue diagnostic instrument to collect standardized tongue images of people with Yang deficiency constitution, Yin deficiency constitution and balanced constitution. and use tongue image analysis software (TDAS) to quantitatively analyze tongue color, tongue texture and tongue coating area. Pearson correlation analysis was used to explore the correlation between tongue characteristics and TCM constitution. Four machine learning algorithms, including SVM, decision tree, random forest, and XGboost were used to build a TCM constitution identification model based on tongue features and evaluate the model's effectiveness.Results: The results show that XGboost has the highest accuracy rate among the four machine learning algorithms and the best performance in model evaluation. Pearson correlation analysis found a specific correlation between TCM constitution and tongue features. Significant correlations existed between the Yang deficiency constitution, Yin deficiency constitution, and the balanced constitution with 16 tongue features. In addition, the model's accuracy for the group 2 containing 16 tongue features was higher than that of the whole feature group (Group 1). XGboost was the most effective in this study for identifying TCM constitution, and the tongue features filtered by correlation analysis led to higher accuracy of TCM constitution identification.Conclusions: Tongue feature information can be an essential reference for TCM constitution identification. Machine learning provides a method for rapid identification of TCM constitution types. The XGboost TCM constitution identification model with good performance gives a new way for clinical " Identifying TCM Constitution by Tongue Image" implementation offers a reference and contributes to the performance of " Preventive Treatment of Disease" of TCM and individualized diagnosis and treatment and health preservation. In addition, Objective identification technology has opened up a new way to modernize TCM diagnosis and treatment.

This paper analyzed the issue of high housing prices in China in view of exotic options using the traditional BSM and improved it while applying it to the current situation in the real estate market. A certain set time frame in the purchase of the options with real estate prices was designed in the implementation of exotic option pricings to ease the speculative pressures caused by high housing prices.

Vascular dementia (VD) is the only type of dementia that can be prevented and treated. Compared to conventional treatment methods, moxibustion therapy is more effective for VD. This study evaluated the effectiveness and safety of moxibustion in the treatment of VD through a meta-analysis, to provide a complete overview to the advantages of traditional Chinese medicine and provide guidance for clinical application.Clinical trials on the therapeutic effects of moxibustion or moxibustion combined with acupuncture on VD were retrieved from the VIP information database, Wanfang, CNKI, PubMed, EMBase, and other resources. The included studies were conducted from January 2000 to October 2020. Among the retrieved studies, the content met the standards upon being collated and extracted, and RevMan5.3 was used for meta-analysis.Thirteen randomized controlled trials (RCTs) were included with 997 patients. The RevMan bias risk assessment revealed that the quality of the studies was generally low. The meta-analysis showed that compared to conventional treatments, moxibution therapy in terms of effective rate, posttreatment Hasegawa Dementia Scale, Mini-Mental State Examination (MMSE), Activity of Daily Living Scale (ADL), Somatostatin (SS), Arginine Vasopressin (AVP), and Syndrome Differentiation Scale of VD were more favorable, and the difference in efficacy was statistically significant. Furthermore, no adverse events were observed in either group. Sensitivity analysis showed strong homogeneity and stable results, whereas funnel plot analysis revealed no significant publication bias.Moxibustion is effective and safe in the treatment of VD, but more high-quality evidence from further studies is required to support this.

The mechanical behaviours of FeCoNiCrCu high entropy alloys (HEAs) were studied via large-scale molecular dynamics (MD) simulations. A rigid indenter was applied in the indentation to investigate the microstructural evolution and mechanical properties of HEAs in terms of indentation force, Young’s modulus, dislocation behaviours, and shear strain distributions. Effects of Cu precipitation on the mechanical properties of HEAs were discussed. The modulus calculated from simulations were inconsistent with experiments. The precipitation of Cu will increase the elastic modulus of the matrix, while the solution of Cu into the matrix can increase the work strengthening rate. The coherent interface of Cu precipitation can contribute to a high work strengthening rate, while the incoherent interface will lead to a lower deformation resistance.

On-chip optical communications are growingly aiming at multimode operation together with mode-division multiplexing to further increase the transmission capacity. Optical switches, which are capable of optical signals switching at the nodes, play a key role in optical networks. We demonstrate a 2 × 2 electro-optic Mach–Zehnder interferometer-based mode- and polarization-selective switch fabricated by standard complementary metal–oxide–semiconductor process. An electro optic tuner based on a PN-doped junction in one of the Mach–Zehnder interferometer arms enables dynamic switching in 11 ns. For all the channels, the overall insertion losses and inter-modal crosstalk values are below 9.03 and –15.86 dB at 1550 nm, respectively.

{(ZrO2)0.92(Y2O3)0.08}1-x(Cr2O3)x solid solution is composed by co-precipitation method and the effects of Cr2O3 content on thermal analysis, crystal structure, microstructure and electrical conductivity are researched. The results discuss the potential for application as a diffusion barrier material at temperatures between 600 and 850 °C to the limiting current oxygen sensors. TG and DSC results show that the main weight loss and heat absorption processes occur below 600 °C and the {(ZrO2)0.92(Y2O3)0.08}1-x(Cr2O3)x solid solution is obtained above 600 °C. XRD analysis shows that the solid solution is fluorite type cubic phase and the solubility of Cr2O3 in (ZrO2)0.92(Y2O3)0.08 is less than 0.10. The SEM-EDS results show that the grain size of the sintered body decreases with increasing Cr2O3 content and distribution of each element is uniform. The conductivity of solid solution decreases first and then increases as Cr2O3 doping content, reaches the maximum value of 4.33 × 10−3 S cm−1 at 850 °C. The doping of Cr2O3 is beneficial to improve the conductivity of the solid solution at low temperature.

A series of (8YSZ)1-x(CeO2)x (0 ≤ x ≤ 0.3) materials are synthesized by co-precipitation. Both crystalline structure and electrical conductivity of material are detected. (8YSZ)1-x(CeO2)x (0 ≤ x ≤ 0.3) belongs to cubic phase and (8YSZ)0.9(CeO2)0.1 is provided with the highest electrical conductivity. Select 8YSZ as solid electrolyte and (8YSZ)0.9(CeO2)0.1 as dense diffusion barrier to prepare an oxygen sensor by Pt paste bonding method. Limiting current plateau of the sensor is observable at 2% oxygen concentration and at 720–900 °C, and logarithm of the limiting current (log IL) plays a linear relationship to 1000/T. Limiting current of the sensor is observable at 850 °C and 2–14% oxygen concentration, which is linearly related to the oxygen concentration. The limiting current of the sensor does not vary significantly in the range of water vapor pressure (p(H2O)) 280.66–2268.63 Pa and in the range of carbon dioxide concentration 0–90%, respectively. The limiting current of the sensor does not decay in the oxygen concentration of 2% at 850 °C during the detection time of 120 h.

{(ZrO2)0.92(Y2O3)0.08}1-x(CuO)x (ZYC) synthesized by the co-precipitation method with different stoichiometry (x=0, 0.1, 0.2 and 0.3) are evaluated through thermogravimetric-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD) and electrical conductivity using an electrochemical workstation and the effects of CuO doping content on the above properties are researched, respectively. The results are discussed in terms of the potential as diffusion barrier material to be applied in diffusion barrier limiting current oxygen sensors application at temperatures from 500 to 850 °C. Results derived from TG-DSC shows that the weight loss of the sample is mainly due to the decomposition of the precursor, forming ZYC above ~600 °C. XRD analysis shows that the ZYC sample is a cubic phase and the CuO doping is benefit to the crystallinity of ZYC. The electrical conductivity results indicate that the total conductivity decreases for ZYC1 but then increases with the increase of CuO doping content and reaches the maximum total conductivity of 2.02 × 10−1 S cm−1 at 850 °C and the activation energy (Ea) is 0.93 eV for ZYC3.