A multi-sensor-based distributed real-time measurement system for glacier deformation

Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation.

On-Machine Measurement of the Straightness and Tilt Errors of a Linear Slideway Using a New Four-Sensor Method

Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing precondition.In this paper, a new four-sensor method with an improved measurement system is proposed to on-machine separate the straightness and tilt errors of a linear slideway from the sensor outputs, considering the influences of the reference surface profile and the zero-adjustment values. The improved system is achieved by adjusting a single sensor to di erent positions. Based on the system, a system of linear equations is built by fusing the sensor outputs to cancel out the e ects of the straightness and tilt errors. Three constraints are then derived and supplemented into the linear system to make the coe cient matrix full rank. To restrain the sensitivity of the solution of the linear system to the measurement noise in the sensor outputs, the Tikhonov regularization method is utilized. After the surface profile is obtained from the solution, the straightness and tilt errors are identified from the sensor outputs. To analyze the e ects of the measurement noise and the positioning errors of the sensor and the linear slideway, a series of computer simulations are carried out. An experiment is conducted for validation, showing good consistency. The new four-sensor method with the improved measurement system provides a new way to measure the straightness and tilt errors of a linear slideway, which can guarantee favorable propagations of the residuals induced by the noise and the positioning errors.

Shapley Value for Cooperative Games with Fuzzy Coalition

Fuzzy Shapley values are developed based on conventional Shapley value. This kind of fuzzy cooperative games admit the representation of rates of players＇ participation to each coalition. And they can be applicable to both supperadditive and subadditvie cooperative games while other kinds of fuzzy cooperative games can only be superadditive. An explicit form of the Shapley function on fuzzy games with λ-fuzzy measure was also proposed.

Consensus for High-Order Linear Multi-Agent Systems with Unknown but Bounded Measurement Noises

The staticε-consensus problem for a high-order linear multi-agent system is studied over a connected undirected communication topology,in which the state measurements of neighbors are affected by unknown but bounded(UBB)noises.Using the dead-zone function and binomial coefficients,we propose a distributed consensus protocol.Under this protocol,all agents achieve staticε-consensus,i.e.,the first components of the states for each agent reachε-consensus,and the remaining components reach agreement at zero.Numerical examples illustrate the validity of the theoretical results.

Non-contact angle measurement based on parallel multiplex laser feedback interferometry

We present a novel precise angle measurement scheme based on parallel multiplex laser feedback interferometry （PLFI）, which outputs two parallel laser beams and thus their displacement difference reflects the angle variation of the target. Due to its ultrahigh sensitivity to the feedback light, PLFI realizes the direct non-contact measurement of non- cooperative targets. Experimental results show that PLFI has an accuracy of 8＂ within a range of 1400＂. The yaw of a guide is also measured and the experimental results agree with those of the dual-frequency laser interferometer Agilent 5529A.

Analysis on the Guarantee for the Quality Safety of Agricultural Products by the Farmer Professional Cooperative

Decentralized production model of small peasant household is main threat for China food safety source. By using the advantage of farmer professional cooperative in controlling the quality of agricultural products,its dilemma at the guarantee aspect of agricultural product quality safety is analyzed,and the guaranteeing measures of farmer professional cooperative for quality safety of agricultural products are proposed,which has an important significance for improving quality safety of agricultural products.

Legislative Perfection of Governance Structure of Farmer Professional Cooperatives in China

The development of modern agriculture can not be separated from the development of farmer professional cooperatives,and the core of sustainable development of the cooperatives lies in the formation of relatively perfect governance structure.Chapter IV of Law on Farmer Professional Cooperatives of People's Republic of China stipulates the organization structure of cooperatives.However,because of historical reasons and limitation of legislative techniques,there is much omission in the institutional regulation of cooperative governance.Due to inadequate system supply of farmer professional cooperatives and deficiency in related rights and obligations,normative guidance can not be provided for the governance practice of farmer professional cooperatives in China,thereby leading to the inefficiency of cooperative management.Therefore,it is imminent to revise the law.

A Brief Analysis of Development of Tibetan Farmers＇ and Herdsmen＇s Economic Cooperatives--A Case Study of Nagqu Area

Through on-the-spot survey and research on the actual situation of agricultural cooperatives and the conditions of production and living of farmers and herdsmen in Nagqu,Tibet,going through a lot of literature,this paper studies and analyzes the development of local cooperative organizations of farmers and herdsmen,understands the actual benefits of cooperative organizations to farmers and herdsmen,aims to increase the income of farmers and herdsmen,and thus puts forward the main problems and measures on agricultural cooperatives in Nagqu area,in order to offer some suggestions for farmers and herdsmen to get rid of poverty through the conclusion of the study.

Development and Economic Effect of Farmers' Specialized Cooperatives

The paper introduces the present development of farmers' specialized cooperatives in China, points out that although the cooperatives in China develop rapidly, they are generally small and their advantages cannot be given into full play, and then analyzes the development achievements of the cooperatives, for example, they have realized scale benefits, their management system tends to more mature, the economic value of their brands is improved and they have created great economic benefits. The paper also points out the stable development path for the cooperatives, that is, the cooperatives should cooperate with local villages, and take a path of combined village and cooperative development so that the cooperative members can get a stable income; the cooperatives can also cooperate with local leading enterprises, which can help the cooperatives to manage, sell and form their products brands, thus the cooperatives can get loans easily to solve the capital bottleneck of cooperative development and improve the members' incomes.

Three-dimensional finite-time cooperative guidance for multiple missiles without radial velocity measurements

In order to simultaneously attack a target with impact angle constraint in threedimensional(3-D) space, a novel distributed cooperative guidance law for multiple missiles under directed communication topologies is proposed without radial velocity measurements. First, based on missiles-target 3-D relative motion equations, the multiple missiles cooperative guidance model with impact angle constraint is constructed. Then, in Line-of-Sight(LOS) direction, based on multiagent system cooperative control theory, one guidance law with directed topologies is designed with strict proof, which can guarantee finite time consensus of multiple missiles' impact times. Next, in elevation direction and azimuth direction of LOS, based on homogeneous system stability theory and integral sliding mode control theory, two guidance laws are proposed respectively with strict proof, which can guarantee LOS angles converge to desired values and LOS angular rates converge to zero in finite time. Finally, the effectiveness of the designed cooperative guidance law is demonstrated through simulation results.

ON THE NON－COMPACTNESS OF THE CORE OF NONATOMIC CONVEX σ－CONTINUOUS MEASURE GAMES

This paper concerns with the core of nonatomic games of form f(μ), where μ is a nonatomic nonnegative measure and f is a continuous convex function on the domain of μ. The main result of this paper is that the core of the game is not compact under the norm topology unless the game itself is a measure. This shows the largeness of the core in a sense other than that defined by Sharky for finite cases.

医护合作多站点宣教模式对高危人工流产患者避孕效果及满意度的影响

目的:探讨医护合作多站点宣教模式对高危人工流产患者避孕知识的掌握、避孕措施的落实及满意度的影响。方法:选取2021年6月至2021年10月本院收治的高危人工流产患者400例为研究对象,随机分为观察组(200例)和对照组(200例)。对照组常规实施流产后关爱,观察组在对照组的基础上,设立计划生育门诊、PAC咨询室、术前宣教室3个宣教站点,实施医护合作多站点宣教模式,两组均随访1年。比较两组避孕知识的掌握、高效避孕措施立即落实、满意度情况,观察两组患者术后1个月、3个月、6个月、12个月的重复流产率、高效避孕措施续用率、随访应答率。结果:与对照组比较,观察组患者对避孕知识的掌握、高效避孕措施立即落实、满意度、高效避孕措施的续用率及随访应答率更优,重复流产率更低,P<0.05,差异均具有统计学意义。结论:医护合作多站点宣教模式可提高高危人工流产患者的避孕节育风险意识,提升高效避孕措施立即落实率和满意度,降低重复流产率的发生,减少流产带来危害,保护其生殖健康。

不均匀光照下的合作目标图像分割方法

针对复杂光照条件下目标测量中,合作目标图像很难被快速、准确分割这一难题,将模糊积分引入图像分割领域,改进传统的局部自适应阈值算法。首先,采用面积求和表(SAT)算法求出合作目标图像的积分图像;其次,根据模糊测度和所选择的离散模糊积分公式计算模糊积分图像;最后,根据模糊积分图像计算每个像素点的阈值,对原图像进行二值化。实验结果表明,改进后的基于模糊积分的局部自适应阈值算法分割的平均结构相似性(SSIM)指标相较于改进前普遍提升了10%~30%,分割效率大幅提升,最终成功地分割合作目标图像。

国际产学研合作影响因素、动机机制与策略研究

如何进一步巩固国际产学研合作基础,促进其持续发展且保持活力,是当前我国推进高水平对外开放,构建国际科技合作新格局必须回答的重要时代课题.提出了新时代“一高二优三特”六位一体国际产学研合作策略体系,为推动国际产学研合作高水平发展提供了方向.具体地:全面掌握国际产学研合作主体的合作信息和资源,为巩固国际产学研合作打造一块扎根深厚的合作高地;从国内国际两方面识别国际产学研合作“内外联动”的影响因素,为探索合作机制提供了前提;细致剖析国际产学研合作“主辅相承”合作模式及“推拉调和”动力机制,培育出两点潜力充足的国际产学研合作优势,从而促进国际产学研合作的持续发展;从文化、制度、管理方面探索了国际产学研合作的保障体系,形成3个旗帜鲜明的合作特色,从而确保国际产学研合作的长久活力.

应对气候变化单边贸易措施的协调治理路径探析

由于应对气候变化单边贸易措施涉及贸易和气候的关系问题,《联合国气候变化框架公约》和WTO分别在立法和司法层面采取了行动并取得了一些进展。但二者在规制与气候变化有关的单边贸易措施时有着各自的局限性,加之二者的规制实践存在着程序和规则方面的差异,导致无法形成一致且有效的治理效果。因此,通过正式的机构合作和具体的制度协调有助于弥合差异并为有效规制与气候变化有关的单边贸易措施作出贡献。

多矢量姿态测量算法研究综述

将矢量测量转化为姿态测量,该问题在姿态估计中被称为Wahba问题。介绍了最小化Wahba问题的损失函数的不同算法,包括最优四元数估计器(ESOQ)、四元数估计器(QUEST)、快速最优姿态矩阵(FOAM)、矩阵的奇异值分解(SVD)等广泛使用的算法,以及基于快速线性四元数姿态估计器(FLAE)、黎曼流形等近年来提出的算法。给出了简单的计算原理与推导过程,并通过计算机仿真对照,归纳各类算法在计算旋转矩阵时的计算精度、鲁棒性。针对姿态测量算法应对当前应用场景的性能需求,简要介绍其在惯性测量单元(IMU)动态对准、协同集群视觉定姿、图像拼接等方面的适用可能和工作原理,并在此基础上简述了姿态测量算法当前的缺陷与未来的发展趋势。

基于校企合作的城市轨道交通运营管理专业实践教学体系改革研究

校企合作是提升城市轨道交通运营管理专业实践教学效果的重要途径。通过与企业合作,高校可根据企业的用人需求和行业标准对教学内容与方法进行针对性调整,从而培养出国家需要、企业满意的人才。因此,探讨研究基于校企合作的城市轨道交通运营管理专业实践教学体系改革措施对培养高素质高质量的城市轨道交通运营管理专业人才具有积极意义。

加强校际教学合作 提高人才培养质量

为提高人才培养质量,要加强校际教学合作,做好顶层设计,完善校际教学合作相关管理体制和运行机制。该文基于学生校际交流学习,促进人才培养模式的优化创新,以优势互补为原则,充分实现校际优质教育资源的共享,助力学校实现高水平应用型人才培养目标。

基于激光雷达的非合作航天器姿态测量

针对目标自遮挡导致姿态解算精度较低的问题,提出了一种基于激光雷达(LiDAR)点云的空间非合作目标姿态估计方法。初始姿态获取阶段,通过RANSAC算法与曲率聚类分割算法对目标特征分割,再与模板特征进行匹配获得粗配准变换矩阵,然后利用迭代最近点(ICP)算法精配准解算初始姿态;姿态跟踪阶段,通过快速点云配准计算相对姿态,通过逐帧点云姿态传递完成目标姿态测量。利用卫星模型搭建实验平台进行姿态测量实验。实验结果表明:所提方法能够稳定完成姿态解算,验证了所提方法的精度与可行性。

基于5G信号异步时钟误差补偿的多无人机协同定位方法

5G信号可为多无人机(UAV)提供精确的相对测距/测角信息,进而提升其在卫星接收机故障时的协同定位精度。然而,协同网络中各节点的5G通讯时钟往往是异步的,这会对测距/测角信息的精度产生较大影响,进而降低融合性能。针对上述问题,提出了一种基于5G信号异步时钟误差补偿的多无人机协同定位方法。首先,构建了基于5G信号异步时钟误差的相对测距模型,并利用相对测距/测角信息以及高度计信息建立了从机的位置观测方程。在此基础上,通过设计迭代扩展卡尔曼滤波器(IEKF)实现了对从机惯导系统(INS)误差以及异步时钟误差的联合最优估计,提高了从机定位精度。仿真结果表明,相比于传统方法,所提方法将从机的水平定位精度提高了25.3%。