Evaluation of behaviors of earth and rockfill dams during construction and initial impounding using instrumentation data and numerical modeling

In this study,the behavior of Gavoshan dam was evaluated during construction and the first impounding.A two-dimensional（2D） numerical analysis was conducted based on a finite difference method on the largest cross-section of the dam using the results of instrument measurements and back analysis.These evaluations will be completed in the case that back analysis is carried out in order to control the degree of the accuracy and the level of confidence of the measured behavior since each of the measurements could be controlled by comparing it to the result obtained from the numerical model.Following that,by comparing the results of the numerical analysis with the measured values,it is indicated that there is a proper consistency between these two values.Moreover,it was observed that the dam performance was suitable regarding the induced pore water pressure,the pore water pressure ratio r;,settlement,induced stresses,arching degree,and hydraulic fracturing probability during the construction and initial impounding periods.The results demonstrated that the maximum settlement of the core was 238 cm at the end of construction.In the following 6 years after construction（initial impounding and exploitation period）,the accumulative settlement of the dam was 270 cm.It is clear that 88% of the total settlement of the dam took place during dam construction.The reason is that the clay core was smashed in the wet side,i.e.the optimum moisture content.Whereas the average curving ratio was 0.64 during dam construction; at the end of the initial impounding,the maximum amount of curving ratio in the upstream was 0.81,and the minimum（critical） amount in the downstream was 0.52.It was also concluded that this dam is safe in comparison with the behaviors of other similar dams in the world.

Modelling of an hydraulic excavator using simplifiedrefined instrumental variable(SRIV)algorithm

Instead of establishing mathematical hydraulic system models from physical laws usually done with the problems of complex modelling processes, low reliability and practicality caused by large uncertainties, a novel modelling method for a highly nonlinear system of a hydraulic excavator is presented. Based on the data collected in the excavator＇s arms driving experiments, a data-based excavator dynamic model using Simplified Refined Instrumental Variable （SRIV） identification and estimation algorithms is established. The validity of the proposed data-based model is indirectly demonstrated by the performance of computer simulation and the.real machine motion control exoeriments.

Extending Instrumental Variable Method for Effective Economic Modelling

Economic modeling that yields practical value must cater for effects caused by exogenous variables. AutoRegressive eXogenous approach (ARX) has been widely used in regional economic studies. Instrumental Variable Method is regarded as a preferential method to parametric estimation in ARX modeling. However, traditional instrumental variable methods can only handle single variable which has limited its capability. This paper presents an extended instrumental variable method (EIVM) which is based on multiple variables. This provides the capability of taking into account of exogenous variables and reflects better the economic activities. A case study is conducted, which illustrates the application of the EIVM in modeling Northeastern economy in China.

A Method for Modeling the Virtual Instrument Automatic Test System Based on the Petri Net

Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is developed by CAT lab of the UESTC as an example. Then a method to model this system based on Petri net is proposed. Through this method, we can analyze the test task scheduling to prevent the deadlock or resources conflict. At last, this paper analyzes the feasibility of this method.

基于UI-Model体系结构的虚拟仪器研究

针对虚拟仪器应具备的可设计性、扩展性与复用性的特点,提出了UI-Model体系结构,将仪器的操作与算法逻辑分离,解决了仿真实验的设计性难题,并设计与实现了基于这种体系结构的虚拟光学仪器.

Establishing a rat model of spastic cerebral palsy by targeted ethanol injection

Spastic cerebral palsy is generally considered to result from cerebral cortical or pyramidal tract damage. Here, we precisely targeted the left pyramidal tract of 2-month-old Sprague-Dawley rats placed on a stereotaxic instrument under intraperitoneal anesthesia. Based on the rat brain stereotaxic map, a 1-mm hole was made 10 mm posterior to bregma and 0.8 mm left of sagittal suture. A microsyringe was inserted perpendicularly to the surface of the brain to a depth of 9.7 mm, and 15 wL of ethanol was slowly injected to establish a rat model of spastic cerebral palsy. After modeling, the rats appeared to have necrotic voids in the pyramidal tract and exhibited typical signs and symptoms of flexion spasms that lasted for a long period of time. These findings indicate that this is an effective and easy method of establishing a rat model of spastic cerebral palsy with good reproducibility. Ethanol as a chemical ablation agent specifically and thoroughly damages the py- ramidal tract, and therefore, the animals display flexion spasms, which are a typical symptom of the disease.

Iterative identification of output error model for industrial processes with time delay subject to colored noise

To deal with colored noise and unexpected load disturbance in identification of industrial processes with time delay, a bias-eliminated iterative least-squares(ILS) identification method is proposed in this paper to estimate the output error model parameters and time delay simultaneously. An extended observation vector is constructed to establish an ILS identification algorithm. Moreover, a variable forgetting factor is introduced to enhance the convergence rate of parameter estimation. For consistent estimation, an instrumental variable method is given to deal with the colored noise. The convergence and upper bound error of parameter estimation are analyzed. Two illustrative examples are used to show the effectiveness and merits of the proposed method.

Using Autocorrelation Analysis to Build the Evaluating Model of Train Impulse Grade

To the shortage of the traditional analysis methods about train impact,this paper put forward a new method us- ing autocorrelation theory and virtual instrument technology to analyze train impulse Using a double-MCU system,the accelera- tion signals were acquired at different speed by train,and were transmitted into PC through USB interface.Besides the impulse signals,the acquisition data included other useless signals.The autocorrelation function was small when trains run steadily,but was greater during train impact happened.So the autocorrelation function was adopted to distill the valid impulse data.After frequency domain analyzed and autocorrelation analyzed on the Virtual Instrument flat,a new train impulse grade assessment cri- terion was built,based on the correlation peak and the width of the peak.In experiment,the impulse signal was separated from noise signal well and truly,and the quantitative model of evaluating train impulse was believable.This system possessed a certain extent theory value and application value.

Prospects of the Hard X-Ray Instrument POLAR to Measure Polarization of Solar Flares

In-depth studies of solar flares emissions and energy releases include analyses of polarization data. Polarization gives clear information about mechanisms and processes leading to electron acceleration and photon production. Despite of many past attempts, the key energy range of hard X-rays was only rarely explored and results were inconclusive. To large extend it was due to greater instrumental complications. Currently several novel polarimeters are either to be employed or under constructions for both balloon and satellite based observations. The novel hard X-ray polarimeter POLAR is an instrument developed by a collaboration between Switzerland, China and Poland. It is primarily designed for high accuracy polarization measurements from the prompt photon emissions of the gamma-ray bursts. The satellite orientation and instrument pointing direction make it also capable for precise measurements of polarization in solar flares. The instrument should fly in near future onboard of the Chinese Space Station TG2.

Automation of choice of instrumental equipment and study of thermo-stressed conditions of metal-cutting instrument

This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite element method.

A Pure Mathematical Relationship between Pitch and Position for Stringed Instruments

In this paper, a simple mathematical model was proposed to answer such a question: what’s the relationship between the finger pressing position and the corresponding pitch for stringed instruments? Furthermore, we compared the theoretical results with measurement results which were obtained from a guitar to prove that the model we propose is reliable. Result shows that relative errors of theoretical results and measurement results are from 0.18% to 1.8%. The mathematics model is more concise, direct and clear than physical model.

基金会现场总线技术在SmartPlant Instrumentation中的应用

详细介绍了现场总线中已得到广泛应用的基金会现场总线(FF)在自控工程设计和管理服务软件(SmartPlant Instrumentation)中的应用。包括FF仪表定义、FF仪表创建、FF仪表接线等多方面内容。

Prediction of lute acoustic quality based on soundboard vibration performance using multiple choice model

The vibrational performance of wood materials critical affects the acoustic quality of a lute. The purpose of this research was to apply a multiple choice model to predict the quality of musical instruments based on data on lute soundboard vibrational properties of Paulownia wood. In the lute production, lute material selection mainly depends on the subjective evaluation of technicians, which is not only inefficient, but inaccurate. In this study, nine lutes were fabricated. Using the multiple selection model, the lute tone quality was predicted by the soundboard wood vibration data. Compared with the actual value, the dependent value predicted by the count of observations with the maximum probability had 22 erroneous judgments. The model precision is 87.78%. The results confirmed that the prediction model can be used as a guideline for the selection of the soundboard wood in musical instrument plants.

高等教育、区域创新能力与数字经济发展

在加快建设数字中国的时代背景下,对高等教育与数字经济之间的关系进行探索有助于优化高等教育的定位和资源配置,并赋能经济社会高质量发展。本研究基于2011—2020年我国各省份的面板数据,实证探究高等教育对区域数字经济发展的影响效应、作用机制和异质性特征。研究发现,高等教育是区域数字经济发展的重要推动力量,其正向影响效应在使用工具变量缓解内生性问题后仍然稳健;区域创新能力是高等教育驱动数字经济增长的有效机制;高等教育对数字经济的贡献具有明显的时序动态性和区域异质性。基于研究结果,未来我国应彰显数字经济发展中的高校力量,通过探索数字创新人才培养体系、实施差异化产学研融合策略以及优化高等教育资源配置等举措,加快构建高等教育与数字经济协同发展的新格局。

基于动力学模型的手术器械夹持力估计研究

手术器械夹持力估计问题一直是微创手术机器人手术器械研究的重点。在微创手术过程中,夹持力过大会造成组织损伤,夹持力过小会使缝合针等脱落,引发危险。因此,研究如何估计手术器械夹持力是非常有必要的。根据手术器械的结构特点,提出了一种基于动力学模型的夹持力估计方法。建立的模型考虑了手术器械动力学模型、丝传动系统力和位移传递特性和直流电动机特性,得到了手术器械电动机电流和夹持力之间的关系;通过Matlab对夹持力模型进行仿真验证,得到了手术器械末端执行器随电动机电流变化的夹持力变化曲线。仿真结果表明,基于动力学模型的手术器械夹持力估计模型与实际情况相符,为后续的手术器械夹持力安全保障研究提供了理论依据。

Study of Load Modeling Technology on Hardware-in-the-Loop Simulator of Gun Servo System

A hardware-in-the-loop (HWIL) simulator for gun servo system is described in this paper, and its load modeling technologies,such as road spectrum model,sea wave model are studied. The simulation results show that the models can be used in HWIL and satisfy the requirements of hardware-in-the-loop simulator of gun servo system.

“项目式”与“混合式”教学方法相结合在仪器分析实验课的教学改革与实践

传统的“观摩式”教学以教师为中心,缺乏师生互动,加之实验课考核力度不够,学生实践能力得不到充分锻炼,存在的问题日益突出。为了能够培养适应市场需求的应用型人才,我们采用了“项目式”和“混合式”教学方法相结合的方式,重新构建实验课程考核评价体系,两种教学模式相得益彰,以学生为中心,有助于培养学生实践技能、分析与解决问题的能力。

热带气旋对南方水稻产量影响的实证检验——基于广东水稻种植户的调研数据分析

【目的】量化因热带气旋导致的水稻产量损失,认识热带气旋灾害对农户生计和粮食安全的影响,为减少热带气旋灾害对水稻生产影响和提升热带气旋灾害的综合防范能力提供数据支撑与政策依据。【方法】运用2020—2022年广东省水稻种植户的混合截面数据,利用Tobit模型和2SLS模型,基于农户地块数据,从微观层次分析热带气旋导致水稻倒伏的影响和水稻倒伏对水稻产量的影响。【结果】热带气旋灾害在1%显著水平上导致水稻倒伏,即当热带气旋过境时水稻倒伏的可能性大大增加。从广东2020、2021、2022年连续3年农户调查数据来看,由热带气旋引起的倒伏率占全部倒伏率的22.9%;水稻倒伏率每增加10%,水稻产量大约下降2.9%。热带气旋对同一地区不同农户及不同地块上的水稻倒伏及产量的影响存在差异,对沿海地区水稻生产的影响要强于内陆地区。【结论】广东热带气旋灾害导致水稻倒伏,进而对水稻产量产生显著影响,危及粮食安全。为减少热带气旋灾害对广东水稻产量的负面影响,提出如下政策启示:进一步完善农田水利设施,加大高标准农田建设力度,确保因热带气旋导致的洪水能迅速排除;培育耐淹或抗倒伏的水稻品种,并在沿海地区进行推广;做好灾害性气候信息传达,加强热带气旋灾害预警系统建设;进一步完善粮食生产保险政策,提高赔付标准和赔付力度。

Mobile businessprocess modelingusinghigh level Petri nets

This paper aims at providing an effective modeling methods for more and more mobile business applications. First a high level Petri nets method-Xml nets is introduced, which combines the advantage of Petri nets and XML. Petri nets have strict mathematics and intuitionistic diagram ex- pression way, rich system describing means and system behavior analytical technology, and the re- lated powerful supporting tools. XML, as an extensible markup language, is already a information description de facto standard. XML nets could be utilized to model both the controlling flow and the data flow of mobile business process effectively, which consequently enables the analysis and optimi- zation of the mobile business processes and could be utilized to simulate the execution of the mobile business process with the Petri nets tools to improve the system execution efficiency. In this paper, to demonstrate the modeling of the controlling flow and data flow of mobile business process, an in- strument repair business case is modeled with XML nets.

数字普惠金融对林业产业发展的影响——基于空间面板模型的实证研究

基于2011—2021年中国31个省份(港澳台地区除外)的面板数据,运用双向固定效应模型以及SDM空间杜宾模型实证分析数字普惠金融对林业产业发展的影响与空间传导机制。研究发现:(1)数字普惠金融对林业产业发展具有显著促进作用,且该结论通过安慰剂检验以及Bartik工具变量等稳健性检验后仍然成立;(2)数字普惠金融对林业产业发展具有异质性,具体表现为区域异质性、生态文明发展程度异质性以及维度异质性;(3)基于空间杜宾模型的实证研究发现数字普惠金融推动林业产业发展具有空间传导效应,本地区数字普惠金融的发展成为拉动周边地区林业产业发展的核心驱动力;(4)由莫兰指数以及莫兰散点图得出林业产业具有“高-高”聚集以及“低-低”聚集的正向空间自相关特征。基于以上研究结论,相关部门应该因地制宜找到适合自己地区发展的数字普惠金融发展战略以推动林业产业的发展。