A Study of the Strategy of Acquisition of the Second Language Productive Vocabulary

Vocabulary is the basic element of a language,and the core part of language learning.English vocabulary can be divid ed into receptive vocabulary and productive vocabulary.Language learners often focus on the former,but ignore the latter.How ever,productive vocabulary plays an important role in language learning.This article makes an in-depth analysis for the relation ship between them then gives some suggestions to language learners who are learning vocabulary.

The second natural gas hydrate production test in the South China Sea

Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017.Based on the understanding of the first production test,the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment,numerical and experimental simulation,and onshore testing of the reservoirs.After that,it conducted the second offshore NGH production test in 1225 m deep Shenhu Area,South China Sea(also referred to as the second production test)from October 2019 to April 2020.During the second production test,a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met,including wellhead stability,directional drilling of a horizontal well,reservoir stimulation and sand control,and accurate depressurization.As a result,30 days of continuous gas production was achieved,with a cumulative gas production of 86.14×104 m3.Thus,the average daily gas production is 2.87×10^4 m^3,which is 5.57 times as much as that obtained in the first production test.Therefore,both the cumulative gas production and the daily gas production were highly improved compared to the first production test.As indicated by the monitoring results of the second production test,there was no anomaly in methane content in the seafloor,seawater,and atmosphere throughout the whole production test.This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs.The industrialization of hydrates consists of five stages in general,namely theoretical research and simulation experiments,exploratory production test,experimental production test,productive production test,and commercial production.The second production test serves as an important step from the exploratory production test to experimental production test.

Solution of the Matrix Second Semi-Tensor Product Equation A ∘ l X ∘ l B=C

In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time, the compatibility conditions, the sufficient and necessary conditions and the specific solution methods for the matrix solution are given. Secondly, we further consider the solvability of the second semi-tensor product equation of the matrix. For each part, several examples are given to illustrate the validity of the results.

Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice

The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively.

Networked Evolutionary Model of Snow-Drift Game Based on Semi-Tensor Product

This paper investigates the networked evolutionary model based on snow-drift game with the strategy of rewards and penalty. Firstly, by using the semi-tensor product of matrices approach, the mathematical model of the networked evolutionary game is built. Secondly, combined with the matrix expression of logic, the mathematical model is expressed as a dynamic logical system and next converted into its evolutionary dynamic algebraic form. Thirdly, the dynamic evolution process is analyzed and the final level of cooperation is discussed. Finally, the effects of the changes in the rewarding and penalty factors on the level of cooperation in the model are studied separately, and the conclusions are verified by examples.

Optimization of post-warranty sequential inspection for second-hand products

This paper considers an optimal sequential inspection schedule for a second-hand product after that the free nonrenewable warranty is expired. The length of warranty is prespecified and during the warranty period, the product is minimally repaired by the dealer when it fails. Following the expiration of the non-renewing warranty, the product is inspected and upgraded sequentially a fixed number of times at the expenses of the customer.At each inspection, the failure rate of the product is reduced proportionally so that the product is upgraded. The product is assumed to deteriorate as it ages and the replacement of the product occurs when a fixed number of inspections are rendered. In addition,the intervals between two successive inspections are assumed to decrease monotonically. The main objective of this paper is to determine the optimal improvement level to upgrade the product at each inspection so that the expected maintenance cost during the life cycle of the product is minimized from the perspective of the customer. Under the given cost structures, we derive an explicit formula to obtain the expected maintenance cost incurred during the life cycle of the product and discuss the method to find the optimal level of the improvement analytically in case the failure times follow the Weibull distribution. Numerical results are analyzed to observe the impact of relevant parameters on the optimal solution.

ZTE FTTx Product Grabs Second BBWF InfoVision Award

ZTE Corporation＇s next-generation xPON optical access platform has won the InfoVision Green Broadband Award at Broadband World Forum Europe （BBWF Europe） 2010 held in Paris, France. This is the second time a ZTE FTTx product has won an Infovision award at this prestigious telecommunications industry event, following a win in 2007.

THEORY AND APPLICATION OF FRACTIONAL STEP CHARACTERISTIC FINITE DIFFERENCE METHOD IN NUMERICAL SIMULATION OF SECOND ORDER ENHANCED OIL PRODUCTION

A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced （chemical） oil production in porous media. Some techniques, such as the calculus of variations, energy analysis method, commutativity of the products of difference operators, decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l^2 norm is derived. This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields, and the simulation results ate quite interesting and satisfactory.

徒手旋转胎头术在头位难产产妇第二产程分娩中的协助应用观察

目的:分析徒手旋转胎头术在头位难产产妇第二产程分娩中的协助应用效果。方法:回顾性分析2020年1月至2023年12月于本院分娩的56例头位难产产妇资料,依据第二产程是否使用徒手旋转胎头术分为两组,各28例。对照组采取传统第二产程分娩助产护理,观察组采取第二产程徒手旋转胎头术,统计产程总时间、新生儿神经行为评分、分娩结局并进行对比。结果:观察组的第二分娩产程明显短于对照组,观察组产程总时间明显短于对照组(P<0.05),第一和第三产程两组无明显统计差异(P>0.05);观察组新生儿神经行为各项评分均高于对照组(P<0.05);观察组阴道裂伤、新生儿窒息及产后出血率均低于对照组(P<0.05)。结论:第二产程徒手旋转胎头术的运用能够改善头位难产产妇分娩结局、促进新生儿神经行为发育、缩短产程总时间,具有一定的推广使用价值。

基于L波段探空观测的FY-4A云顶温度产品评估及其在冬季降水相态判识中的应用

利用2019—2021年冬季上海宝山站L波段探空资料对FY-4A云顶温度(CTT)产品进行评估,分析发现,FY-4A的云顶温度产品能够较好地反映单层云的云顶温度,对双层云或多层云的云顶温度则普遍高估(平均高估幅度超过14℃);当探空观测到的云顶高度不超过6 km或云顶温度不低于-20℃时,FY-4A云顶温度产品误差较小,平均偏差约为3℃。根据2021—2022年冬季长三角地区地面站观测的降水现象统计云顶温度与降水相态的关系,并对典型个例进行分析,结果表明,云顶温度低是出现降雪的必要条件之一,绝大部分降雪出现在云顶温度低于-12℃的情况下。FY-4A的云顶温度产品时空分辨率高、精度尚可,可以辅助预报员判识雨雪落区,在雨雪转换过程的预报服务中有较大的应用潜力。

Self-Triggered Set Stabilization of Boolean Control Networks and Its Applications

Set stabilization is one of the essential problems in engineering systems, and self-triggered control(STC) can save the storage space for interactive information, and can be successfully applied in networked control systems with limited communication resources. In this study, the set stabilization problem and STC design of Boolean control networks are investigated via the semi-tensor product technique. On the one hand, the largest control invariant subset is calculated in terms of the strongly connected components of the state transition graph, by which a graph-theoretical condition for set stabilization is derived. On the other hand, a characteristic function is exploited to determine the triggering mechanism and feasible controls. Based on this, the minimum-time and minimum-triggering open-loop, state-feedback and output-feedback STCs for set stabilization are designed,respectively. As classic applications of self-triggered set stabilization, self-triggered synchronization, self-triggered output tracking and self-triggered output regulation are discussed as well. Additionally, several practical examples are given to illustrate the effectiveness of theoretical results.

Semi-tensor product approach for partially symmetric games

In this paper,a criterion for the partially symmetric game(PSG)is derived by using the semitensor product approach.The dimension and the basis of the linear subspace composed of all the PSGs with respect to a given set of partial players are calculated.The testing equations with the minimum number are concretely determined,and the computational complexity is analysed.Finally,two examples are displayed to show the theoretical results.

“学二代”成长中的继承与反叛——关于文化再生产理论的本土阐释

“学二代”因其优厚的家庭文化资本而有别于其他“二代”群体。作为具有高知家庭背景的“学二代”,在自身的成长脉络中却可能存在诸多“难言之隐”。通过对14位“九零后”“学二代”的成长脉络进行深入细致的叙事研究,发现在“学二代”自我寻觅之旅中有着对于家庭文化资本的继承、超越和反叛,看似顺遂的成长之路却充满冲突和拉扯。在顺应父辈期望的文化再生产与建构自我的文化生产的对峙中,他们正在探寻着一种与家庭文化资本保持距离的方式,寻找着文凭之外的出路,并展现出新知识分子对于教育的后现代性目光。

继代培养球孢白僵菌对斜纹夜蛾幼虫毒力和产孢量的影响及菌株复壮研究

【目的】明确球孢白僵菌(Beauveria bassiana)在连续继代培养过程中对斜纹夜蛾(Spodoptera litura)二龄幼虫毒力、产孢量的影响,并进行菌种复壮研究,为进一步利用球孢白僵菌对斜纹夜蛾的生物防治提供参考。【方法】将球孢白僵菌SCAUJH19继代培养10代,得到F_(1)~F_(10)代菌株并测定产孢量。采用浸虫法分别用F_(1)~F_(10)代菌株处理斜纹夜蛾二龄幼虫,测定其对斜纹夜蛾二龄幼虫的毒力;建立模型分析球孢白僵菌继代培养代数、毒力与产孢量的关系及毒力退化规律。采用活虫复壮法对F_(4)、F_(6)、F_(8)、F_(10)代菌株进行复壮,比较复壮前后对斜纹夜蛾二龄幼虫的毒力效果,并测定产孢量。【结果】球孢白僵菌F_(1)~F_(5)代菌株对二龄斜纹夜蛾幼虫毒力无显著差异,处理7 d时校正死亡率为42.44%~45.22%,而F_(6)、F_(8)、F_(10)代菌株对二龄斜纹夜蛾幼虫的校正死亡率分别降至37.00%、22.94%、12.17%。F_(1)~F_(5)代菌株产孢量为9.65~10.43×10^(8)CFU/mL,F_(6)、F_(8)、F_(10)代菌株产孢量分别降至7.62×10^(8)、5.14×10^(8)、4.69×10^(8)CFU/mL。建立模型发现,菌株继代培养到F_(5)代后,产孢量随培养代数呈现指数下降,且产孢量与毒力存在一定的正相关关系,继代培养代数较少的菌株产孢量较高,对斜纹夜蛾二龄幼虫的致病力较强。通过活虫复壮法对F_(4)、F_(6)、F_(8)、F_(10)代菌株进行复壮后,菌株对斜纹夜蛾二龄幼虫的校正死亡率均>50%,且均高于原始菌株的最高致死率,复壮后菌株的产孢量均高于复壮前的产孢量。【结论】球孢白僵菌在继代培养4~5代后,产孢量逐代下降,对斜纹夜蛾二龄幼虫的毒力也逐代降低,需进行菌种复壮;采用活虫复壮法可将继代后的球孢白僵菌恢复或提高至原有特性;同一菌株的产孢量可作为评价其毒力的参考指标。

二序理解在语意学转向下的设计意义

利益相关者对人工物往往有着自身独特的理解,为了使设计师能够对这些理解进行理解,就需要将二序理解融入设计师的思维之中。关于设计中的二序理解的研究离不开语意学转向的支持,也同样需要语义学理论的支持。基于以人为本的设计与设计的语意学转向,文章在利益相关者对彼此以及人工物的理解中展开对二序理解的研究,得到了二序理解在设计中的实现方式,进而讨论了二序理解在某些维度上对设计的意义。

大规模阵列Kronecker稳健波束形成器

针对大规模阵列对样本需求量大、计算复杂度高的问题,提出一种应用于大规模阵列的Kronecker自适应稳健波束形成器。首先,将期望信号导向矢量分解成两个导向矢量的Kronecker乘积,将原始导向矢量的失配问题转化为两个低维导向矢量的失配问题;然后,基于最坏情况性能最优原理建立双二次代价函数,并利用双迭代算法求解该代价函数,每次迭代过程只需求解两个低维的二阶锥规划问题。理论分析和仿真实验结果表明,与传统全维稳健算法相比,所提方法能够有效降低计算复杂度和样本需求量,与现有的降维稳健算法相比,由于具有更多自由度,所提方法具有更高的输出信干噪比。

积极心理学视角下二语口语产出中的情绪体验及影响因素研究

从积极心理学视角出发,采用量化和质性相结合的研究方法,探究高职院校的英语学习者在二语口语产出中的外语愉悦、外语焦虑水平及其影响因素。实证结果显示,高职学生在二语口语产出中体验到中等程度的外语愉悦及较高程度的外语焦虑,且外语焦虑水平显著高于外语愉悦水平。二语口语产出中的外语愉悦主要受教师个性特征、教师情感与评价支持,口语活动内容、难度与组织方式,课堂氛围等学习者外部因素影响;外语焦虑主要受英语水平,自我效能感,个性特征等学习者内部因素影响。该研究有助于全面把握二语学习者的情绪特征,对构建积极的二语课堂,开展二语教学实践,尤其是口语教学具有重要的教学启示。

新时代基于“四位一体”的医学英语混合式教学改革

文章从长期历史的角度探索了新时代基于“四位一体”的医学英语混合式教学改革实践。依据最新的国家政策、基于使用的二语习得观以及外语教学方法,自2021年9月以来,从教学目标、教学内容、教学设计以及课程评价等4个方面对山东省某医学院校医学英语课进行三轮改革,并通过调查问卷了解改革效果。问卷结果显示,学生认为课程知识、能力与素质目标几乎完全符合其学习需求和英语水平,对线上课程、线下教学内容、线下教学方法以及课程考核方式的满意度均高于90%。基于“四位一体”的医学英语混合式教学改革基本达到了预期效果。

剖宫产术后再次妊娠经阴道分娩状况及影响因素分析

目的:探讨剖宫产术后再次妊娠经阴道分娩状况及影响因素。方法:回顾性收集2021年1月至2024年1月期间在本院分娩的剖宫产术后再次妊娠产妇的临床资料。所有产妇均进行阴道试产,并根据最终产妇分娩方式的不同,将产妇分为经阴道分娩组(阴道试产成功,n=36)和剖宫产组(阴道试产失败转剖宫产,n=14)。收集比较两组的基线资料,分析比较导致产妇试产失败的独立危险因素。结果:本研究50例剖宫产术后再次妊娠产妇,经阴道试产成功率为72.00%(36/50),中转剖宫产率28.00%(14/50)。Logistic回归分析显示,孕期增重不合理、宫颈成熟评分<6分、妊娠间隔时间不足4y、胎儿双顶径过大、产妇情绪焦虑都是导致剖宫产再次妊娠产妇经阴道试产失败的独立危险因素。结论:剖宫产术后再次妊娠产妇经阴道分娩试产成功率为72.00%,孕期增重不合理、宫颈成熟评分<6分、妊娠间隔时间不足4y、胎儿双顶径过大、产妇情绪焦虑都是导致剖宫产再次妊娠产妇经阴道试产失败的独立危险因素。

税收补贴政策下考虑二手市场电子产品回收供应链成员的博弈策略研究

考虑由一个制造商、一个回收商及二手市场组成的两层供应链结构,分别构建了仅回收商回收的决策模型、回收商回收与二手市场交易共存的决策模型,基于消费者效用分析了供应链成员的最优产品定价策略,探讨了二手市场的引入对电子产品回收供应链成员决策及税收补贴政策设计的影响。结果显示:在一定条件下,二手市场交易的竞争一方面使消费者在电子产品回收中获益,另一方面也提高了制造商的利润及政府税收补贴剩余。但是,二手市场交易的竞争致使回收商的利润降低,政府可以适当提高对回收商的产品回收补贴来增强回收商的竞争力,降低回收商的利润损失。此外,本文证明了从社会总福利的角度看待开发二手市场是大有裨益的。