Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index

The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity.

Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database

Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally.

Decentralized Semi-Supervised Learning for Stochastic Configuration Networks Based on the Mean Teacher Method

The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy of decentralized SCN algorithms while effectively protecting user privacy. To this end, we propose a decentralized semi-supervised learning algorithm for SCN, called DMT-SCN, which introduces teacher and student models by combining the idea of consistency regularization to improve the response speed of model iterations. In order to reduce the possible negative impact of unsupervised data on the model, we purposely change the way of adding noise to the unlabeled data. Simulation results show that the algorithm can effectively utilize unlabeled data to improve the classification accuracy of SCN training and is robust under different ground simulation environments.

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.

Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction

As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value.

基于改进AdvSemiSeg的半监督遥感影像作物制图方法

作物精准遥感制图对于农业资源调查与管理具有重要意义。深度学习为实现精准高效作物制图提供了技术支持。为了缓解深度学习对标记样本的依赖,本文提出了一种改进AdvSemiSeg的半监督遥感影像作物制图方法。所提方法引入STMF-DeepLabv3+作为对抗学习中的生成网络,通过Swin Transformer(ST)和多尺度特征融合(Multi-scale fusion, MF)模块提高生成网络特征编码能力和语义表达能力,改善遥感影像作物分割效果;此外,在判别网络中引入通道注意力(Efficient channel attention, ECA)模块,对不同通道特征图的表征信息进行自适应学习,增强判别网络对不同通道特征的感知能力。模型训练过程中,判别网络为生成网络提供高质量的伪标签和对抗损失,有效提高生成网络的泛化能力。采用所提方法与几种先进的半监督语义分割方法对内蒙古河套灌区遥感影像种植信息进行提取,本文方法性能最优。

基于事件触发的奇异semi-Markov跳变系统的有限时间控制

为减少不必要的网络资源传输,解决实际复杂系统的有限时间问题,提出一种基于事件触发方案的奇异semi-Markov跳变系统的有限时间控制器设计方法。在事件触发方案下,用系统的时滞表示网络诱导时延,闭环系统可以建模为一个时滞系统。首先,通过构造合适的Lyapunov-Krasovskii泛函,以严格矩阵不等式的形式给出充分条件,以使事件触发方案下的闭环系统正则、无脉冲、随机有限时间有界;然后,通过求解矩阵不等式,得到状态反馈控制器的参数;最后,给出一个数值示例,通过仿真证明所提方法的有效性。

SEMI标准在半导体制造设备中的应用

SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料的使用效率标准、SECS/GEM通讯标准及其研究应用现状;提出了我国半导体产业的快速发展需要加大SEMI标准的普及应用。

Inequalities for Scalar Curvature and Shape Operator of an R-Lightlike Submanifold in Semi-Riemannian Manifold

We establish the links between the lightlike geometry and basics invariants of the associated semi-Riemannian geometry on r-lightlike submanifold and semi-Riemannian constructed from a semi-Riemannian ambient. Then we establish some basic inequalities, involving the scalar curvature and shape operator on r-lightlike coisotropic submanifold in semi-Riemannian manifold. Equality cases are also discussed.

基于多核CPU的无锁并行Semi-naive算法

Datalog系统被广泛应用于很多领域,如图数据库、网络和静态程序分析等。在处理海量数据时,基于串行的Datalog求解策略无法充分发挥现有多核处理器的计算性能。针对上述问题,提出一种基于多核CPU的无锁并行Semi-naive算法(Parallel Semi-naive, PSN)用于支持Datalog的高效求解。PSN使用B+树索引进行数据划分,将数据分配给不同的线程执行计算,每个分区产生的中间结果元组互不相同,有利于实现计算时无锁的并行。同时提出一种双层哈希表结构来索引中间结果以提高查重的效率,每个线程只在特定的区域执行相关的计算,无需使用锁来防止写冲突。PSN使用任务队列-线程池为空闲线程分配任务,来实现多线程的负载均衡。在KONECT(Koblenz Network Collection)及斯坦福SNAP(Stanford Network Analysis Platform)的公开数据集上的实验结果表明,PSN算法可以优化Datalog规则的查询性能。

基于PI的Semi-Markovian电力系统事件触发控制设计分析

基于PI控制器设计理论,本文对电力系统负荷频率的稳定性问题进行分析,提出改进的事件触发机制,对带有不确定性半马尔可夫跳变参数的电力系统进行数学均值期望处理,整理构建成随采样信号状态变化而自适应调整的闭环系统。考虑随机跳变多模态下系统中的干扰影响和时滞虚拟延迟,设计模态依赖控制器,结合矩阵叉积不等式和Schur补定理等,对泛函导数积分项进行放缩,将最优值问题转化为解线性矩阵不等式,最终利用Matlab工具箱求解,求出控制增益和事件触发矩阵,给出系统随机稳定性判据,对系统H∞性能指标进行分析。本文所设计方案可以提高通信网络中控制信号的传输率,有效减轻电网信息输送负担,在节约能源的同时还能提高系统的动态性能。

Radar emitter signal recognition method based on improved collaborative semi-supervised learning

Rare labeled data are difficult to recognize by using conventional methods in the process of radar emitter recogni-tion.To solve this problem,an optimized cooperative semi-supervised learning radar emitter recognition method based on a small amount of labeled data is developed.First,a small amount of labeled data are randomly sampled by using the bootstrap method,loss functions for three common deep learning net-works are improved,the uniform distribution and cross-entropy function are combined to reduce the overconfidence of softmax classification.Subsequently,the dataset obtained after sam-pling is adopted to train three improved networks so as to build the initial model.In addition,the unlabeled data are preliminarily screened through dynamic time warping(DTW)and then input into the initial model trained previously for judgment.If the judg-ment results of two or more networks are consistent,the unla-beled data are labeled and put into the labeled data set.Lastly,the three network models are input into the labeled dataset for training,and the final model is built.As revealed by the simula-tion results,the semi-supervised learning method adopted in this paper is capable of exploiting a small amount of labeled data and basically achieving the accuracy of labeled data recognition.

The Delivery of Grand Multiparas in a Semi-Rural Setting: A Cross-Sectional Descriptive Study at the Ayos Locality of Cameroon

Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the maternity of the regional hospital annex of Ayos, a semi-rural locality in the Center region of Cameroon. The study covered the period from January 2012 through December 2020, and the objective was to assess the frequency, the determinants and the outcome of delivery in grand multiparas. Results: We recorded 1384 deliveries and enrolled 137 cases of delivery of grand multiparas. This gives a frequency of grand multipara delivery of 9.89%. The mean age of the women was 34.96 ± 4.45 years. Married parturients accounted for 65% of the cases and 16.8% were HIV positive. Delivery occurred at term in 89.9%. In 35.8%, no antenatal consultation was done. The use of the partograph during labor was reported in 11.7%. Per vaginal delivery was noted in 88.3%, emergency cesarean in 10.2% and elective cesarean in 1.5%. The most frequent maternal complications included post-partum hemorrhage (19.9%), genital tract tears (12.4%), endometritis (9.5%) and surgical wound infection (8.7%). No maternal death was recorded. The mean birth weight of the newborns was 3336.8 ± 550 g. Fetal complications were mostly represented by neonatal infection (20.1%), perinatal death (7.9%) and neonatal asphyxia (9.5%). Conclusion: The frequency of grand multiparous delivery in the semi-rural locality of Ayos, Cameroon, was 9.89%. The mean age of parturients was 38.96 years and the proportion of vaginal delivery was 88.3%.

Features and Patterns of Primipara Delivery in a Cameroon Semi-Rural Area: The Case of Ayos Locality

Introduction: The delivery of a primipara, a woman giving birth for the first time, is challenging and may lead to complications and influence the obstetrical future of a woman. Materials and Methods: We carried out a cross-sectional and analytical study at the maternity of the regional hospital annex of Ayos, a semi-rural locality in Cameroon, for the period between January 2012 and December 2020. The objective was to determine the frequency and the determinants of primipara delivery. Results: We recruited 440 cases. The frequency of primipara delivery was 31.8%. The ages of the participants ranged from 12 to 35 years with a mean age of 18.01 ± 3.52 years. Single women contributed to 95.5% of cases while 97.5% were unemployed. The delivery occurred at term in 90.2% and 98.4% of pregnancies were singleton. The delivery was vaginal in 91.6%, while caesarean delivery was done in 8.4% (8% emergency and 0.4% elective). The most frequent maternal complications were genital tract tears (15.7%), post-partum hemorrhage (12.5%) and endometritis (2.7%). The birth weight of newborns ranged from 1070 to 4500 g with a mean of 3024.5 ± 511.4 g. The single marital status, a gestational age between 37 and 42 weeks and a birth weight between 1500 g and 2499 g were significantly associated with vaginal delivery. Conclusion: The frequency of primiparous delivery was relatively high (31.8%) in the Ayos semi-rural health district of Cameroon. Major complications associated with delivery included genital tract tears, post-partum hemorrhage, cesarean section and neo-natal infection.

Exploring the Potential of Cowpea-Wheat Double Cropping in the Semi-Arid Region of the Southern United States Using the DSSAT Crop Model

Information is limited on the potential of double-cropping cowpea (Vigna unguiculata L.) and wheat (Triticum aestivum L.) in the semiarid region of the southern United States. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data of 80 years, we assessed the possibility of cowpea-wheat double-cropping in this region for grain purpose as affected by planting date and N application rate. Results showed that the possibility of double-cropping varied from 0% to 65%, depending on the cropping system. The possibility was less with systems comprising earlier planting dates of wheat and later planting dates of cowpea. Results indicated that cowpea-wheat double-cropping could be beneficial only when no N was applied, with wheat planted on October 15 or later. At zero N, the double-crops of cowpea planted on July 15 and wheat planted on November 30 were the most beneficial of all the 72 double-cropping systems studied. With a delay in planting cowpea, the percentage of beneficial double-cropping systems decreased. At N rates other than zero, fallow-wheat monocropping systems were more beneficial than cowpea-wheat double-cropping systems, and the benefit was greater at a higher N rate. At 100 kg N ha-1, the monocrop of wheat planted on October 15 was the most beneficial of all the 94 systems studied. Results further showed that fallow-wheat yields increased almost linearly with an increase in N rate from 0 to 100 kg∙ha-1. Fallow-wheat grain yields were quadratically associated with planting dates. With an increase in N rate, wheat yields reached the peak with an earlier planting date. Wheat yields produced under monocropping systems were greater than those produced under double-cropping systems for any cowpea planting date. Cowpea yields produced under monocropping systems were greater than those produced under any double-cropping system. The relationship between cowpea grain yields and planting dates was quadratic, with July 1 planting date associated with the maximum yields.

The El Niño-Southern Oscillation (ENSO) Effects on Cowpea and Winter Wheat Yields in the Semi-Arid Region of the Southern US

Information is limited on the effects of climate variability on cowpea (Vigna unguiculata L.) and winter wheat (Triticum aestivum L.) yields in the semiarid region of the southern US. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data spanning 81 years, we assessed the impact of El Niño-Southern Oscillation (ENSO) on the grain yields of these crops in the Llano Estacado region of the southern US as affected by cowpea and wheat planting dates and N application rate. Simulated results showed that the El Niño phase of ENSO produced about 30% more yields of mono-cropped cowpea than those produced under the La Niña phase, especially with the cowpeas planted in July. The cowpea yields under El Niño were about 10% more than the 81-year average normal yield, whereas those under La Niña were about 20% less. At the N rates of 0, 50, and 100 kg·ha−1, regardless of wheat planting dates, the El Niño years produced, respectively, about 8%, 40%, and 60% higher wheat yields than those produced in the La Niña years, and about 5%, 20%, and 27% more than the 81-year average normal yield. In the La Niña years, the wheat yields at 0, 50, and 100 kg N ha−1 were, respectively, about 5%, 15%, and 20% less than the normal yield with similar N levels. The impact of ENSO on wheat yields under cowpea-wheat double-cropping systems was significant, especially for the wheat crops planted on October 15 (October 30) or later following the cowpea crops planted in June (July). At zero N, the mono-cropped wheat yields were not impacted by ENSO due to N limitation. However, the double-cropped wheat yields were impacted by ENSO even when no N fertilizer was applied due to high soil N status caused by N transfer from cowpea stover residues and roots. Results indicated that management strategies need to be attentive to ENSO forecasts and adjust potential planting dates and N application rates with the ENSO phase to avert risks of crop failure and economic loss.

Semi-Pre-HPLC与HPLC-MS联用的二维色谱分析系统对代谢相关脂肪性肝病肝线粒体中滇黄精药源成分的检测

目的检测代谢相关脂肪性肝病(MAFLD)肝线粒体中滇黄精药源成分的分布情况。方法24只6周龄雄性SD大鼠采用随机数字表法分为正常组、模型组和滇黄精水提物组,每组8只。正常组以普通饲料喂养,其他组以高脂饲料喂养。建立模型同时滇黄精水提物组按照8 g/(kg·d)灌胃滇黄精水提物,正常组与模型组灌胃等体积的生理盐水,连续14周。最后一次给药1 h后,取各组大鼠肝组织,分离得到线粒体,采用Semi-Pre-HPLC联合HPLC-MS二维色谱分析系统分析各组肝线粒体药源成分。结果MAFLD大鼠肝线粒体中检测到10种药源成分,其中7种已报道脂代谢调节活性,分别为薯蓣皂苷元、薯蓣皂苷、菝葜皂苷元、Pratioside D1、异甘草素、β-谷甾醇、常春藤皂苷元。结论检测到的10种药源成分可能是滇黄精调节线粒体缓解MAFLD的主要活性物质。

Hematization of Quartz Grains: Study of the Surface of Quartz Grains (M.E.B) and Semi-Quantitative Mineralization

Interest in the Côte d’Ivoire sedimentary basin has led to numerous investigations. All these investigations are aimed at understanding the functioning of the basin and a paleogeographic approach including sediment transport dynamics. However, the use of exoscopy and semi-quantitative mineralogy has been little developed. This study was carried out to compensate for this lack of interest in these methods. Its aim is to understand the transformation of quartz into hematite using exoscopy and semi-quantitative mineralogy in the Adiaké locality, in the eastern onshore basin of Côte d’Ivoire. Two methods were applied to 250 μm-diameter quartz grains from the 40 m coasts. Exoscopy provides information on microscopic texture, surface and corrosion, as well as determining the transport mechanism and deposition phases of quartz grains. Semi-quantitative mineralogy provides an estimate of the weight percentages of major element oxides and the ultrastructure of quartz grains. Exoscopy showed that these grains had been subjected to torrential fluvial transport. They were marked by mechanical and chemical traces during this transport and evolved in different environments. Semi-quantitative mineralogy shows the existence of negative and positive correlations between oxides. Negative correlations indicate a substitution, in order of importance, of silicon by iron, phosphorus and aluminum in these quartz. Positive correlations show that there is no substitution between the oxides concerned in these quartz grains. Divo’s quartz grains have recorded several mechanical and chemical microstructures of their sedimentary episodes, with the appearance of iron nodules in the ports left by silica.

Cementless Semi-Constrained Rotating Platform Total Knee Replacement: A Concise Follow-Up of a Previous Report at a Minimum of Twenty Years

Background: A previous report evaluated the initial 310 cementless, Buechel-Pappas (B-P), Semi-Constrained Rotating Platform total knee replacements in 257 patients followed for an average of 7.6 years, range 2 - 18 years. Diagnoses were osteoarthritis in 233 patients, post traumatic arthritis in 4 patients and rheumatoid arthritis in 22 patients. Knee Scores, using a strict knee scoring scale were 86.4% excellent, 12.3% good, 0.3% fair and 1.0% poor results. Survivorship, using an end point of revision for any mechanical reason (including component loosening, bearing wear and bearing dislocation) was 99.4%. Survivorship for a poor knee score (including persistent pain, loosening, instability and infection was 97.6%. The purpose of the present study is to report the updated results of this same patient cohort at a minimum follow-up of twenty years. Methods: The average age of patients at the time of surgery was 67 years, range 34 to 91 years. A total of 20 patients (22 knees) were still living, with a follow-up of 20 - 30 years (mean 23.47 years). The same strict knee scoring scale and survivorship analysis were used to evaluate patient outcomes at the 20 to 30 years interval. Results: Survivorship, in the current study, using the same end points as in the previous study, was 96.5% at the 20 and 30-year intervals. Late mechanical failure and osteolysis were not identified. Conclusion: This cementless, semi-constrained rotating platform total knee replacement has stood the test of time for more than 20 years and can be considered acceptable for long-term use, in properly selected patients.

基于Semi-Markov模型沥青路面性能衰变规律研究

为解决在路面使用性能预测过程中预测值与实测值间误差波动较大这一问题,采用Semi-Markov模型对山东省某国道的使用性能进行预测,同时将预测结果与实测数据进行对比。结果显示,Semi-Markov模型能够有效预测道路使用寿命,且对早期道路使用状况的预测结果精确度更高,而随着预测年限的延长,预测结果受道路养护措施的影响很大,需采取主动干预措施进行修正,Semi-Markov模型为准确预测沥青路面早期使用性能变化趋势并得到合理的养护决策提供可靠依据。