Constitutive modeling of viscoelastic-viscoplastic behavior of short fiber reinforced polymers coupled with anisotropic damage and moisture effects

In this paper, a combined viscoelasticity-viscoplasticity model, coupled with anisotropic damage and moisture effects, is developed for short fiber reinforced polymers (SFRPs) with different fiber contents and subjected to a variety of strain rates. In our model, a rate-dependent yield surface for the matrix phase is employed to identify initial yielding of the material. When an SFRP is loaded at small deformation before yielding, its viscoelastic behavior can be described using the generalized Maxwell model, while when plasticity occurs, a scalar internal state variable (ISV) is used to capture the hardening behavior caused by the polymeric constituent of the composite. The material degradation due to the moisture absorption of the composite is modeled by employing another type of ISV with different evolution equations. The complicated damage state of the SFRPs is captured by a second rank tensor, which is further decomposed to model the subscale damage mechanisms of micro-voids/cracks nucleation, growth and coalescence. It is concluded that the proposed constitutive model can be used to accurately describe complicated behaviors of SFRPs because the results predicted from the model are in good agreement with the experimental data.

Evaluation of the Application Effect of Short Video Combined with BOPPPS Teaching Mode in Clinical Anesthesia Teaching

Objective:To study the application effect of short video combined with BOPPPS teaching mode in clinical anesthesia practice.Method:48 students assigned to clinical anesthesia in digestive endoscopy of Shanxi Bethune Hospital from July 1,2022 to April 1,2023 were selected as research objects.They were randomly divided into the control group(PowerPoint presentation teaching group)and the observation group(short video combined with BOPPPS teaching group),with 24 students in each group.After the internship,the students’theoretical and technical scores were tested,the effects of the two teaching modes were compared,and the students’satisfaction was investigated.Results:The test scores of students in the observation group were significantly better than those in the control group(P<0.05).The short video combined with BOPPPS teaching mode can significantly improve students’learning interest,operation skills,and memory(P<0.05).The students’satisfaction in the observation group was higher than that in the control group(P<0.05).Conclusion:In clinical practice,the application of short video combined with BOPPPS teaching mode has achieved great effect,which is worth further promotion and research.

SHORT－TIME EFFECTS OF BRONCHIAL ARTERY INFUSION WITH CHEMICAL DRUGS FOR LUNG CANCER

Bronchial artery infusion(BAI)with chemical agents was performed in 41 patients with lung carcinoma up to 61times,included 33 cases(51 times)primary lung carcinoma(PLC)and 8cases(10 times)lung metastatic carcinoma (LMC). Short-time effects were valuable in 31 cases with PLC and 7 cases with LMC.Complete remission(CR)plus partial rimission(PR)ocurred in 14 cases(45.16%)among 31 patients with PLC and 1 case(14.28%)among 14 patients with LMC(P<0 .01).CR plus PR was 10cases(52.63%)among 19 patients with central type cancer (CTC)and 4 cases (33.33%) among 12 patients with perprephal type cancer(PTC) of PLC(P<0.05). CR plus PR in 15 squamous carcinomas(SC),6 adenocarcinomas (AC)2 small cell undifferentiated carcinomas(SCLC)and 8 histologically unclassfied carcinomas(HUC)were 8(53.33%),1(50%),and 3(37.5%), respectively.The rate of CR plus PR in squamous carcinoma was higher than that in adenocarcinoma and histologically unclassified carcinoma(P<0.05).There was no remarkable difference in CR plus PR among stage Ⅱ-Ⅲand Ⅳpatients with PLC, CAP and FMP protocol treatment.This study also investigated and analysed the side effects of 41 patients by BAI treatment.

Clinical Observation on the Improved Short-Term Effects of Anti-Tumor Purified Chinese Medicine Injection Ai-Jing for 138 Cases with Malignant Tumors

The subjects of this study were to observe the improved short-term effects of anti-tumor purified Chinese medicine injection Ai-Jing for 138 cases with malignant tumors. This was a multi-center clinical study, and a total of 138 patients included 96 males and 42 females, with the age from 60 to 76 years. Ai-Jing has obtained the Chinese invention patent since 2008 (ZL991-03528.3). A novel technique acupoint injection method was adopted. Except for lung cancer, patients with other malignant tumors were injected once every other day, 2 ml each time. A course of treatment needs 6 Ai-Jing injections, lung cancer patients need 10 - 20 Ai-Jing injections. At the same time, patients were treated with traditional medicine decoction. Due to the limited number of cases, cure rate, recovery rate and remission rate were calculated as a whole, respectively 18.12%, 44.20% and 32.15%. All the invalid patients were lung cancer, accounting for 16.67% of the patients treated with lung cancer, and the total treatment inefficiency was 6.52%. Conclusion: Chinese Medicine Injection Ai-Jing extracts the effective components of anti-cancer and tumorigenesis, and has the effects of anti-cancer and tumorigenesis, anti-inflam-matory and analgesic, and repairing body damage, with small toxic and side effects and low cost.

GeSi Source/Drain Structure for Suppression of Short Channel Effect in SOI p-MOSFET's

GeSi source/drain structure is purposefully adopted in SOI p MOSFET's to suppress the short channel effect (SCE).The impact of GeSi material (as source only,drain only or both source and drain) on the threshold voltage rolling off and DIBL effect is thoroughly investigated,as well as the influence of the Ge concentration and silicon film thickness.The Ge concentration should be carefully chosen as a tradeoff between the driving current and SCE improvement.The detailed physics is explained.

Temperature Effects on the Electrical Performance of Large Area Multicrystalline Silicon Solar Cells Using the Current Shunt Measuring Technique

The temperature effects on the electrical performance of a large area multicrystalline silicon solar cell with back-contact technology have been studied in a desert area under ambient conditions using the current shunt measuring technique. Therefore, most of the problems encountered with traditional measuring techniques are avoided. The temperature dependency of the current shunt from 5oC up to 50oC has been investigated. Its temperature coefficient proves to be negligible which means that the temperature dependency of the solar cell is completely independent of the current shunt. The solar module installed in a tilted position at the optimum angle of the location, has been tested in two different seasons (winter and summer). The obtained solar cell short circuit current, open circuit voltage and output power are correlated with the measured incident radiation in both seasons and all results are discussed.

NUMERICAL STUDY OF SHORT TERM EFFECT OF SST ANOMALIES

Using a 5-layer P- o mixed coordinates primitive equations model, a process of heavy rain is simulated that occurred over the middle-and lower-reaches of the Changjiang River on July 1- 2, 1991 and numerical experiments are done of the effects of sea surface temperature (SST) anomalies over different waters on the precipitation. The result has shown that the appearance of SST anomaly is followed in a short term (2 or 3 days) by. A change in the pattern of circulation as well as in precipitation to some extent.

Skin Effect of Reversely Switched Dynistor in Short Pulse Discharge Application

The skin effect in the reversely switched dynistor （RSD） devices is investigated in this paper. Based on the plasma bipolar drift model of the RSD, the current density distributions on the chip are simulated with considering the skin effect. The results indicate that the current density on the border can be several hundred to a thousand A/cm2 higher than that in the center of the chip. The skin effect becomes more prominent as the voltage increases and the inductance decreases in the main circuit. The phenomenon that most of a certain group of chips break over on the border has proved the existence of the skin effect.

The Impact of Meteorological Factors on the Short-term Cumulative Effect of Air Particulate in Tianjin

In order to reveal the rapid increase mechanism of particulate concentration in short time,a notion of short-term cumulative effect of air particulate is defined as the significant increase of pollutant concentration in a short time under the condition of breeze,stable weather and constant emission caused by human being's activities. Subsequently,an index of short-term cumulative effect is established with air diffusive equation,and then the macro-scale meteorological situation and micro-scale factors of forming the short-term cumulative effect are discussed with the observation data. The macro-scale meteorological variables contain upper-level weather situations and surface weather situations. The micro-scale factors mainly include the boundary-layer height and boundary-layer stability. The analyses show that boundary-layer factors and weather variables have a significant influence on the short-term cumulative effect. The notion of short-term cumulative effect will play an important role in interpreting the severe pollution weather.

Laboratory Research on Effective Test Area of Short-Crested Waves Generated by Two-Sided Segmented Wavemakers

The size and shape of the effective test area are crucial to consider when short-crested waves are created by segmented wavemakers. The range of the effective test area of short-crested waves simulated by two-sided segmented wavemakers is analyzed in this paper. The experimental investigation on the wave field distribution of short-crested waves generated by two-sided segmented wavemakers is conducted by using an array of wave gauges. Wave spectra and directional spreading function are analyzed and the results show that when the main direction is at a certain angle with the normal line of wave generators, the wave field of 3D short-crested waves generated by two-sided segmented wavemakers has good spatial uniformity within the model test area. The effective test area can provide good wave environments for seakeeping model tests of various ocean engineering structures in the deep ocean engineering basin.

Generation of time-dependent ultra-short optical pulse trains in the presence of self-steepening effect

Starting from the extended nonlinear Schrodinger equation in which the self-steepening effect is included, the evolution and the splitting processes of continuous optical wave whose amplitude is perturbed into time related ultra-short optical pulse trains in an optical fibre are numerically simulated by adopting the split-step Fourier algorithm. The results show that the self-steepening effect can cause the characteristic of the pulse trains to vary with time, which is different from the self-steepening-free case where the generated pulse trains consist of single pulses which are identical in width, intensity, and interval, namely when pulses move a certain distance, they turn into the pulse trains within a certain time range. Moreover, each single pulse may split into several sub-pulses. And as time goes on, the number of the sub-pulses will decrease gradually and the pulse width and the pulse intensity will change too. With the increase of the self-steepening parameter, the distance needed to generate time-dependent pulse trains will shorten. In addition, for a large self-steepening parameter and at the distance where more sub-pulses appear, the corresponding frequency spectra of pulse trains are also wider.

A Study of the Bullwhip Effect for Short Life Cycle Products in Supply Chain Management

Shorter product life cycles present new dressed in supply chain literature. This research challenges to managing production and logistics not adequately adaddresses issues pertaining to the management of supply chains in a short life cycle environment. In this paper, we study the short life cycle environment; then we develop the ventory policy of the indirect manufacturer by explicitly using his demand us an output of the retailer＇s optimal inoptimal ordering policy. Finally, we also provide causes of the bullwhip effect in the context of short life cycle products.

Distributed Generation Effects on Large-Scale Distribution Networks

This paper examines the results of the distributed generation penetration in large-scale medium-voltage power distribution networks. The network examined as a study case consists of twenty one lines fed by three power substations. The injected power comes mainly from photovoltaic units. Specifically, the influences of distributed generation on the network branch currents, losses and voltage profile as well as on the short-circuit level at the medium voltage busbars of the infeeding substations are examined according to international and national standards. The arising problems are explored and technical solutions are proposed. This paper is a pilot application as general conclusions concerning the extended distributed generation penetration in real power distribution networks are set out.

创新要素集聚对农业绿色技术进步空间溢出效应分析

基于2010—2020年中国31个省份的面板数据,采用空间杜宾模型实证分析创新要素集聚对农业绿色技术进步的空间溢出效应。研究结果表明:从全国来看,创新要素集聚对农业绿色技术进步的影响具有明显正向空间溢出效应,不仅驱动本地农业绿色技术进步,还推动邻近地区农业绿色技术进步。创新要素集聚对农业绿色技术进步的空间溢出效应以短期效应为主。从区域来看,沿海、内陆地区创新要素集聚对农业绿色技术进步具有明显空间溢出效应,而沿边地区空间溢出效应不明显。对此,可改善创新要素引入制度、优化地区间创新要素互动机制、构建区域间农业绿色技术进步成果互通平台,持续促进农业绿色技术进步,以实现农业农村可持续发展。

短视频平台公共政策传播的信息框架效应——基于“双减”政策的视频内容分析与实验

[目的/意义]短视频作为新兴的互联网信息表达方式,已逐渐成为政策传播的重要工具。探索短视频平台在公共政策信息传播中的效力以及受众采纳意愿,有助于提升公共政策传播效果。[研究设计/方法]以“双减”政策为例,根据框架效应理论和信息采纳理论,通过内容分析法归纳总结短视频平台中“双减”政策信息框架的组织方式,同时分析不同政策信息框架对传播效果的影响;此外,采用在线控制实验法验证了不同政策信息框架对受众采纳意愿的影响。[结论/发现]在短视频平台中有近四成的信息使用了目标框架,其中损失框架居多,多数采用集体主义视角和非叙事陈述方式;目标框架、文化框架、叙事框架对受众的评论、转发、点赞意愿并未产生显著影响;双减政策信息中,损失、收益框架,集体、个人主义价值观以及叙事和非叙事要素都能增强受众的采纳意愿,并且目标框架与文化框架之间存在交互效应。[创新/价值]研究结论对于政策宣传部门及相关政府机构优化政策传播策略,提高传播效果具有启示作用。

Characteristic Analysis of Short Time Heavy Rain in Yulin, China

National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, China on August 7, 2018. The result shows that the strong convective weather occurred in peripheral subtropical high over west pacific, being caused by short wave disturbance, and surface convergence lines with positive pressure variation are corresponding to areas of short-time heavy precipitation. The degree of temperature change in cold pool caused by thunderstorm may decide the intensity of a short-time rainfall, and local topography plays an important role in extreme precipitation. Local water vapour accumulation and water vapour flux convergence in the middle and lower layers support adequate moisture condition in the process. Moving direction and development direction of mesocale convective cloud are in a line to develop the train effect, leading to local short-time heavy rain in Yulin city, Shaanxi, China.

含贝达喹啉全口服短程化疗治疗耐多药肺结核疗效及安全性观察临床研究

目的:探讨含贝达喹啉全口服短程化疗治疗耐多药肺结核患者的疗效及安全性。方法:选择100例耐多药肺结核患者,以随机数字表法将其分为对照组(WHO长疗程方案)50例和观察组(含贝达喹啉全口服短程方案)50例。比较两组患者痰培养阴转率、治愈率,并行胸部CT检查,观察病灶及空洞变化,并记录不良反应率发生情况。结果:观察组24周阴转率为84.00%(41/50)高于对照组74.00%(27/50),观察组36周时病灶吸收及空洞改善好于对照组(P<0.05)。观察组终点治愈率76.00%(38/50)高于对照组治愈率52.00%(26/50)(P<0.05)。对照组治疗过程中共出现不良反应84例次,观察组共出现不良反应69例次,两组不良反应发生情况比较,差异有统计学意义(P<0.05)。结论:含贝达喹啉全口服短程化疗方案治疗耐多药肺结核疗程短、治愈率高、安全性良好。

特高压电网不等高差短导线的受力性能

目前中国的特高压电网技术得到了快速发展。然而,工程中常由于忽视对导线受力性能的分析而酿成绝缘事故。根据导线两端挂线点的空间位置,其连接方式可分为等高差导线连接和不等高差导线连接。为此,本文提出了一种计算不等高差短导线端子在不同方向上受力性能的经验公式。通过改变挂线点之间的水平间隔距离、竖直高度差两个因素,开展了不同空间布局组合状态下的导线端子的受力特性分析,提出了可供设计参考的导线端部力学分析公式。结果表明经验公式具有良好的工程适用性。导线两端的受力特性不仅与环境荷载有关,与导线型号、两端竖直高度差、两端水平间隔距离等因素有关。

适用于SiC MOSFET的漏源电压积分自适应快速短路保护电路研究

SiC MOSFET因其高击穿电压、高开关速度、低导通损耗等性能优势而被广泛应用于各类电力电子变换器中。然而,由于其短路耐受时间仅为2~7μs,且随母线电压升高而缩短,快速可靠的短路保护电路已成为其推广应用的关键技术之一。为应对不同母线电压下的Si C MOSFET短路故障,文中提出一种基于漏源电压积分的自适应快速短路保护方法(drain-sourcevoltageintegration-basedadaptivefast short-circuit protection method,DSVI-AFSCPM),研究所提出的DSVI-AFSCPM在硬开关短路(hardswitchingfault,HSF)和负载短路(fault under load,FUL)条件下的保护性能,进而研究不同母线电压对DSVI-AFSCPM的作用机理。同时,探究Si CMOSFET工作温度对其响应速度的影响。最后,搭建实验平台,对所提出的DSVI-AFSCPM在发生硬开关短路和负载短路时不同母线电压、不同工作温度下的保护性能进行实验测试。实验结果表明,所提出的DSVI-AFSCPM在不同母线电压下具有良好的保护速度自适应性,即母线电压越高,短路保护速度越快,并且其响应速度受Si CMOSFET工作温度影响较小,两种短路工况下工作温度从25℃变化到125℃,短路保护时间变化不超过90 ns。因此,该文为Si CMOSFET在不同母线电压下的可靠使用提供一定技术支撑。