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End-point dynamic control of basic oxygen furnace steelmaking based on improved unconstrained twin support vector regression 被引量:1
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作者 Chuang Gao Ming-gang Shen +2 位作者 Xiao-ping Liu Nan-nan Zhao Mao-xiang Chu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2020年第1期42-54,共13页
In order to improve the end-point hit rate of basic oxygen furnace steelmaking,a novel dynamic control model was proposed based on an improved twin support vector regression algorithm.The controlled objects were the e... In order to improve the end-point hit rate of basic oxygen furnace steelmaking,a novel dynamic control model was proposed based on an improved twin support vector regression algorithm.The controlled objects were the end-point carbon content and temperature.The proposed control model was established by using the low carbon steel samples collected from a steel plant,which consists of two prediction models,a preprocess model,two regulation units,a controller and a basic oxygen furnace.The test results of 100 heats show that the prediction models can achieve a double hit rate of 90%within the error bound of 0.005 wt.%C and 15℃.The preprocess model was used to predict an initial end-blow oxygen volume.However,the double hit rate of the carbon con tent and temperature only achieves 65%.Then,the oxygen volume and coolant additi ons were adjusted by the regulation units to improve the hit rate.Finally,the double hit rate after the regulation is reached up to 90%.The results indicate that the proposed dynamic control model is efficient to guide the real production for low carbon steel,and the modeling method is also suitable for the applications of other steel grades. 展开更多
关键词 STEELMAKING basic OXYGEN FURNACE End-point control TWIN support vector regression Wavelet transform
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New deep eutectic solvents composed of crown ether, hydroxide and polyethylene glycol for extraction of non-basic N-compounds 被引量:7
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作者 Mohammad Chand Ali Ruirui Liu +5 位作者 Jia Chen Tianpei Cai Haijuan Zhang Zhan Li Honglin Zhai Hongdeng Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第4期871-874,共4页
Here we firstly report a series of new deep eutectic solvents(DESs) induced by small amounts of crown ether complex and mainly formed by polyethylene glycol. These DESs not only presented the ultra-deep extraction of ... Here we firstly report a series of new deep eutectic solvents(DESs) induced by small amounts of crown ether complex and mainly formed by polyethylene glycol. These DESs not only presented the ultra-deep extraction of non-basic N-compounds from fuel oils, but also opened up the possibility of other new applications in chemistry and materials science. 展开更多
关键词 Deep eutectic solvents EXTRACTION non-basic N-compounds Regeneration Selectivity
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Surface Modification of Biomimetic PLGA-(ASP-PEG) Matrix with RGD-Containing Peptide:a New Non-Viral Vector for Gene Transfer and Tissue Engineering 被引量:3
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作者 郭晓东 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第3期41-43,共3页
RGD-containing peptide ( K16-GRGDSPC) , characterized as non-viral gene vectors, was fabricated to modify the surface of PLGA-[ASP- PEG] matrix, which offered the foundation for gene transfer with porous matrix of g... RGD-containing peptide ( K16-GRGDSPC) , characterized as non-viral gene vectors, was fabricated to modify the surface of PLGA-[ASP- PEG] matrix, which offered the foundation for gene transfer with porous matrix of gene activated later. Peptide was synthesized and matrix was executed into chips A, B and chip C. Chip C was regarded as control. Chips A and B were reacted with cross-linker. Then chip A was reacted with peptide. MS and HPLC were ased to detect the .14W and purity of peptide. Sulphur, existing on the surface of biomaterials, was detected by XPS. The purity of un-reacted peptide in residual solution was detected by a spectrophotometer. HPLC shows that the peptide purity was 94%- 95% , and MS shows that the MW was 2 741. 3307. XPS reveals that the binding energy of sulphur was 164 eV and the ratio of carbon to sulphur (C/S) was 99. 746 :0. 1014 in reacted chip A. The binding energy of sulphur in reacted chip B was 164 eV and 162 eV, C/ S was 99.574:0.4255, aM there was no sulphur in chip C. Peptide was manufactured and linked to the surface of biomimetic and 3-D matrix, which offered the possibilities for gene transfer and tissue engineering with this new kind of non-viral gene vector. 展开更多
关键词 tissue engineering gene transfection biomimetic material non-viral vector RGD peptide
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Ecological Fitness of Non-vector Planthopper Sogatella furcifera on Rice Plants Infected with Rice Black Streaked Dwarf Virus 被引量:5
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作者 HE Xiao-chan XU Hong-xing +4 位作者 ZHENG Xu-song YANG Ya-jun GAO Guang-chun PAN Jian-hong LU Zhong-xian 《Rice science》 SCIE 2012年第4期335-338,共4页
We evaluated the effects of rice black streak dwarf virus (RBSDV)-infested rice plants on the ecological parameters and its relevant defensive and detoxification enzymes of white-backed planthopper (WBPH) in labor... We evaluated the effects of rice black streak dwarf virus (RBSDV)-infested rice plants on the ecological parameters and its relevant defensive and detoxification enzymes of white-backed planthopper (WBPH) in laboratory for exploring the relationship between RBSDV and the non-vector planthopper. The results showed that nymph survival rate, female adult weight and fecundity, and egg hatchability of WBPH fed on RBSDV-infested rice plants did not markedly differ from those on healthy plants, whereas the female adult longevity and egg duration significantly shortened on diseased plants. Furthermore, significantly higher activities of defensive enzymes (dismutase, catalase and peroxidase) and detoxification enzymes (acetylcholinesterase, carboxylesterase and glutathione S-transferase) were found in WBPH adults fed on infected plants. Results implied that infestation by RBSDV increased the ecological fitness of non-vector planthopper population. 展开更多
关键词 ecological fitness rice black streaked dwarf virus non-vector white-backed planthopper
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Basic Tenets of Classification Algorithms K-Nearest-Neighbor, Support Vector Machine, Random Forest and Neural Network: A Review 被引量:15
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作者 Ernest Yeboah Boateng Joseph Otoo Daniel A. Abaye 《Journal of Data Analysis and Information Processing》 2020年第4期341-357,共17页
In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (... In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (RF) and Neural Network (NN) as the main statistical tools were reviewed. The aim was to examine and compare these nonparametric classification methods on the following attributes: robustness to training data, sensitivity to changes, data fitting, stability, ability to handle large data sizes, sensitivity to noise, time invested in parameter tuning, and accuracy. The performances, strengths and shortcomings of each of the algorithms were examined, and finally, a conclusion was arrived at on which one has higher performance. It was evident from the literature reviewed that RF is too sensitive to small changes in the training dataset and is occasionally unstable and tends to overfit in the model. KNN is easy to implement and understand but has a major drawback of becoming significantly slow as the size of the data in use grows, while the ideal value of K for the KNN classifier is difficult to set. SVM and RF are insensitive to noise or overtraining, which shows their ability in dealing with unbalanced data. Larger input datasets will lengthen classification times for NN and KNN more than for SVM and RF. Among these nonparametric classification methods, NN has the potential to become a more widely used classification algorithm, but because of their time-consuming parameter tuning procedure, high level of complexity in computational processing, the numerous types of NN architectures to choose from and the high number of algorithms used for training, most researchers recommend SVM and RF as easier and wieldy used methods which repeatedly achieve results with high accuracies and are often faster to implement. 展开更多
关键词 Classification Algorithms non-PARAMETRIC K-Nearest-Neighbor Neural Networks Random Forest Support vector Machines
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Approximate solution of the spin-one Duffin-Kemmer-Petiau(DKP) equation under a non-minimal vector Yukawa potential in(1+1)-dimensions
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作者 H.Hassanabadi Z.Molaee 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期74-77,共4页
We solve the Duffin-Kemmer-Petiau (DKP) equation with a non-minimal vector Yukawa potential in (1+1)- dimensional spa^e-time for spin-1 particles. The Nikiforov Uvarov method is used in the calculations, and the ... We solve the Duffin-Kemmer-Petiau (DKP) equation with a non-minimal vector Yukawa potential in (1+1)- dimensional spa^e-time for spin-1 particles. The Nikiforov Uvarov method is used in the calculations, and the eigen- functions as well as the energy eigenvalues are obtained in a proper Pekeris-type approximation. 展开更多
关键词 DKP equation non-minimal vector Yukawa potential Nikiforov-Uvarov method
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Dynamic of Non-Autonomous Vector Infectious Disease Model with Cross Infection
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作者 Weiwei Ji Shenghua Zou +2 位作者 Jishang Liu Quanben Sun Lijun Xia 《American Journal of Computational Mathematics》 2020年第4期591-602,共12页
In the article, we established a non-autonomous vector infectious disease model, studied the long-term dynamic behavior of the system, and obtained sufficient conditions for the extinction and persistence of infectiou... In the article, we established a non-autonomous vector infectious disease model, studied the long-term dynamic behavior of the system, and obtained sufficient conditions for the extinction and persistence of infectious diseases by constructing integral functions. 展开更多
关键词 non-AUTONOMOUS Seasonal Variability vector Infectious Disease
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EXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND BASIC FIBROBLAST GROWTH FACTOR IN HUMAN NON-SMALL CELL LUNG CANCER AND THEIR CLINICAL SIGNIFICANCE
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作者 张伟 王洁 +4 位作者 刘叙仪 王曾礼 张毅 刘元林 蒋薇 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第4期259-264,共6页
Objective: To explore the expression of vascular endothelial growth factor(VEGF) and basic fibroblast growth factor(bFGF) in non-small cell lung cancer(NSCLC) and theIR clinical significance. Methods: The expression o... Objective: To explore the expression of vascular endothelial growth factor(VEGF) and basic fibroblast growth factor(bFGF) in non-small cell lung cancer(NSCLC) and theIR clinical significance. Methods: The expression of VEGF and bFGF was examined at the protein levels by immunohistochemical staining in 96 NSCLC patients, and in 36 of which at the mRNA levels by reverse transcription-PCR analysis. Results: VEGF mRNAs were expressed predominately as its secretory forms (VEGF121 and VEGF165) in NSCLC tissues. The positive ratios of VEGF121 and VEGF165 were 69.5%(25 of 36) and 41.7%(15 of 36) respectively. The positive ratio of bFGF was 52.8(19 of 36) in the same tumor specimens. The positive ratios of VEGF and bFGF at protein levels were 55.55%(20 of 36) and 58.33%(21 of 36) respectively. A significant positive correlation was observed between VEGF and bFGF expression in NSCLC tissues(P=0.002). No significant interrelationship between VEGF, bFGF expression and clinical data(age, sex, histological subtype differentiation, P-stage, metastasis and survival) was found. Conclusions: VEGF and bFGF may play an important role in angiogenesis and act in a synergistic manner in NSCLC. 展开更多
关键词 non-small cell lung cancer Vascular endothelial growth factor(VEGF) basic fibroblast growth factor(bFGF)
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Generalization of the Second Order Vector Potential Formulation for Arbitrary Non-Orthogonal Curvilinear Coordinates Systems from the Covariant Form of Maxwell's Equations
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作者 Denis Prémel 《Journal of Electromagnetic Analysis and Applications》 2012年第10期400-409,共10页
A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentia... A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentials in order to obtain analytical expressions of the electromagnetic fields from the two potentials. However, the scalar decomposition is often known for canonical coordinate systems. This paper aims in introducing a specific SOVP formulation dedicated to arbitrary non-orthogonal curvilinear coordinates systems. The electromagnetic field representation which is derived in this paper constitutes the key stone for the development of semi-analytical models for solving some eddy currents moelling problems and electromagnetic radiation problems considering at least two homogeneous media separated by a rough interface. This SOVP formulation is derived from the tensor formalism and Maxwell’s equations written in a non-orthogonal coordinates system adapted to a surface characterized by a 2D arbitrary aperiodic profile. 展开更多
关键词 Second Order vector Potential (SOVP) Curvilinear COORDINATE System EDDY Current non-DESTRUCTIVE Testing (ECNDT)
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The Reform Exploration on the Computer Basic Education of Non-Computer Major under the General Education Model in China
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作者 Jinlan Guo 《Journal of Zhouyi Research》 2014年第2期51-53,共3页
关键词 计算机基础教育 非计算机专业 教育模式 改革 中国 计算机科学 美国大学 课程设置
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Modeling of Non-uniformly Sampled Systems by Support Vector Regression with Applications
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作者 LI Da-hai LI Tian-shi 《International Journal of Plant Engineering and Management》 2010年第3期135-140,共6页
This paper presents a modeling method for a non-uniformly sampled system bused on support vector regression ( SVR ). First, a lifted discrete-time state-space model for a non-uniformly sampled system is derived by u... This paper presents a modeling method for a non-uniformly sampled system bused on support vector regression ( SVR ). First, a lifted discrete-time state-space model for a non-uniformly sampled system is derived by using the lifting technique to reduce the modeling difficulty caused by multirate sampling. Then, the system is divided into several parallel subsystems and their input-output model is presented to satisfy the SVR model. Finally, an on-line SVR technique is utilized to establish the models of all subsystems to deal with uncertainty. Furthermore, the presented method is applied in a multichannel electrohydraulic force servo synchronous loading system to predict the system outputs over the control sample interval and the prediction mean absolute percentage error reaches 0. 092%. The results demonstrate that the presented method has a high modeling precision and the subsystems have the same level of prediction error. 展开更多
关键词 support vector regression multirate sampling non-uniformly sampled systems
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On Basic Parameters and Radiation Theory of Non-Uniform Channel DMOS
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作者 LIZe-hong 《Journal of Electronic Science and Technology of China》 2005年第1期91-92,共2页
关键词 non-uniform channel DMOS basic parameter total ion dose single ion radiation transient response
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非凸推力可行域下的喷水推进船推力分配方法
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作者 丁江明 慕鹏宁 罗腾 《哈尔滨工程大学学报》 北大核心 2026年第1期228-234,共7页
为在喷水推进船舶矢量控制过程中充分利用推进器的性能,本文对喷水推进器特有的非凸推力可行域下的推力分配进行研究。采用区域分配策略和两步优化结构,先将非凸推力可行域划分为多个凸子域进行约束,以避免推力分配时因非凸约束条件导... 为在喷水推进船舶矢量控制过程中充分利用推进器的性能,本文对喷水推进器特有的非凸推力可行域下的推力分配进行研究。采用区域分配策略和两步优化结构,先将非凸推力可行域划分为多个凸子域进行约束,以避免推力分配时因非凸约束条件导致局部最优解,再进行第1步优化计算,得到各喷水推进器的推力指令;然后根据各喷水推进器推力指令确定各喷水推进器运转参数的变化范围,进行第2步优化计算,得到各喷水推进器运转参数指令,从而实现喷水推进船的矢量控制。以一艘喷水推进单体滑行艇为研究对象,对上述方法进行仿真验证,结果表明,该方法能有效处理非凸约束条件下的推力分配问题。 展开更多
关键词 船舶 喷水推进 矢量控制 单手柄操纵系统 推力分配 非凸优化 区域分配 序列二次规划法
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非小细胞肺癌中医证候与病理分型及TNM分期相关性分析
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作者 崔蕊 刘永平 《山西中医》 2026年第2期50-52,共3页
目的:探讨非小细胞肺癌患者中医证候与病理分型及TNM分期的相关性。方法:选取符合纳入标准的非小细胞肺癌患者250例,分析其中医证型分布规律,并探究中医证型与病理类型、TNM分期、吸烟及KPS评分的相关性。结果:250例非小细胞肺癌患者中... 目的:探讨非小细胞肺癌患者中医证候与病理分型及TNM分期的相关性。方法:选取符合纳入标准的非小细胞肺癌患者250例,分析其中医证型分布规律,并探究中医证型与病理类型、TNM分期、吸烟及KPS评分的相关性。结果:250例非小细胞肺癌患者中气阴两虚证最多,其次为气虚痰湿证、气血瘀滞证、阴虚热毒证。病理类型中腺癌最多,其次为鳞癌、混合癌、大细胞癌。根据TNM分期,Ⅳ期患者最多,其次为Ⅲ期、Ⅰ期、Ⅱ期;各中医证型的病理分型比较差异无统计学意义(P﹥0.05);各中医证型的TNM分期比较具有显著相关性(P﹤0.05)。结论:非小细胞肺癌患者中医证型与TNM分期具有显著相关性。 展开更多
关键词 非小细胞肺癌 中医证型 病理分型 TNM分期 KPS评分 临床基础研究
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基因编辑技术及其载体递送系统研究进展
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作者 刘苏楠 白文静 +1 位作者 李佩珊 吕万良 《中国新药杂志》 北大核心 2026年第3期225-236,共12页
基因编辑技术是一类能够对生物体基因组中特定目标基因进行修饰、插入、删除操作的生物技术。本文回顾性叙述了基因编辑的基本原理、基因编辑技术类型、基因编辑药物载体递送系统及其临床应用现状。基因编辑技术的主要类型有锌指核酸酶... 基因编辑技术是一类能够对生物体基因组中特定目标基因进行修饰、插入、删除操作的生物技术。本文回顾性叙述了基因编辑的基本原理、基因编辑技术类型、基因编辑药物载体递送系统及其临床应用现状。基因编辑技术的主要类型有锌指核酸酶、转录激活因子样效应物核酸酶、成簇规律间隔短回文重复序列相关核酸酶、碱基编辑和先导编辑等。基因编辑药物的递送载体主要有腺病毒、腺相关病毒、慢病毒、脂质纳米粒、聚合物纳米粒、外泌体等,其中以重组腺病毒、重组腺相关病毒、脂质纳米粒载体等较为常用。目前,已有3款基因编辑治疗药物获批上市,有多种处于临床试验研究阶段。基因编辑技术主要应用于遗传性疾病、肿瘤、感染性疾病等重大疾病治疗。基因编辑药物正在成为难治性重大疾病有效治愈的变革性治疗新策略。 展开更多
关键词 基因编辑 基因治疗 病毒载体 非病毒载体 临床应用
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提高非计算机专业Visual Basic课程学习兴趣的方法 被引量:5
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作者 程传鹏 《计算机教育》 2011年第18期53-56,共4页
Visual Basic语言是一种基于Windows平台的,面向对象的可视化编程语言,由于其具备了直观、简单易学的特性,因此,很多大学都把VB作为非计算机专业的计算机公共基础课来讲授。本文分析了VB教学在非计算机专业学生中所普遍存在的问题,结合... Visual Basic语言是一种基于Windows平台的,面向对象的可视化编程语言,由于其具备了直观、简单易学的特性,因此,很多大学都把VB作为非计算机专业的计算机公共基础课来讲授。本文分析了VB教学在非计算机专业学生中所普遍存在的问题,结合教学实际,提出了相应的改进方法,这种方法在笔者的实际教学中取得了较好的效果。 展开更多
关键词 VISUAL basic程序设计 非计算机专业 学习兴趣 教学方法
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空间转动坐标系中矢量求导公式的解析几何推导
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作者 张彦 殷桂琴 赵松峰 《物理通报》 2026年第2期15-17,共3页
空间转动坐标系是刚体力学和非惯性系力学中经常采用的一种坐标系,其中的矢量求导运算是导出刚体力学中欧拉动力学方程和非惯性系力学中速度、加速度表达式的关键.本文从解析几何的角度对空间转动坐标系中的矢量求导公式给出了一种新的... 空间转动坐标系是刚体力学和非惯性系力学中经常采用的一种坐标系,其中的矢量求导运算是导出刚体力学中欧拉动力学方程和非惯性系力学中速度、加速度表达式的关键.本文从解析几何的角度对空间转动坐标系中的矢量求导公式给出了一种新的数学推导方法. 展开更多
关键词 转动坐标系 矢量求导 定点转动 非惯性系 理论力学
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激励相容视角下“非粮化”问题的综合治理逻辑与路径研究
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作者 钟晓萍 赵文杰 《中州学刊》 北大核心 2026年第1期66-75,共10页
构建“非粮化”综合治理体系是加力实施新一轮千亿斤粮食产能提升行动的有力举措。面对实践中出现的耕地转作他用或撂荒等现象,我国实行“非粮化”监管且政策趋严,但尚未协调好粮食安全保障与农民利益保障的关系,出现了多元主体激励不... 构建“非粮化”综合治理体系是加力实施新一轮千亿斤粮食产能提升行动的有力举措。面对实践中出现的耕地转作他用或撂荒等现象,我国实行“非粮化”监管且政策趋严,但尚未协调好粮食安全保障与农民利益保障的关系,出现了多元主体激励不相容现象,降低了农民对监管政策的接受度,催生了土地低度利用、“形式化种粮”以及土地流转积极性不高等消极行为响应,不利于粮食安全保障。为应对激励不相容带来的政策目标偏移,应以构建“基本农作物管理体系”为契机,将“非粮化”监管转向“非粮化”综合治理,以清晰界定、明确原则、有序治理优化“非粮化”管理政策,以激励引导、主体赋能促进多元主体激励相容,以夯实基础、节本增效强化激励相容环境建设支持,以技术集成、划定勘误实现技术赋能,从而构建起一套以激励引导为主、监管执行为辅、主体赋能为要、建设支持为基、技术监测为器的“非粮化”综合治理体系,更好服务于国家粮食安全保障。 展开更多
关键词 “非粮化” 激励相容理论 新一轮千亿斤粮食产能提升行动 基本农作物
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非计算机专业“Visual Basic程序设计”课程教学研究 被引量:1
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作者 蒋社想 《长沙通信职业技术学院学报》 2012年第1期100-102,共3页
文章分析了非计算机专业的"Visual Basic程序设计"课程教学普遍存在的问题,结合自身的教学实际,从教学内容、教学方法、考核方式等方面进行改革,建立"网络教学""、实验预约"、"实验考勤监控"... 文章分析了非计算机专业的"Visual Basic程序设计"课程教学普遍存在的问题,结合自身的教学实际,从教学内容、教学方法、考核方式等方面进行改革,建立"网络教学""、实验预约"、"实验考勤监控"等教学平台,利用这些平台,有效地提高了"Visual Basic程序设计"在非计算机专业的教学效果。 展开更多
关键词 Visualbasic程序设计 非计算机专业 网络教学平台 教学效果
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基于兴趣培养的非计算机专业Visual Basic课程教学探讨
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作者 李志辉 《现代计算机》 2013年第6期24-27,31,共5页
针对非计算机专业学生学习Visual Basic课程兴趣不高而造成教学目标难以有效达成的问题,提出运用类比法讲概念、巧设认知冲突悟新知、精选趣味案例乐中学的教学思路,在教学实践中取得了较好的效果,极大地提高学生的学习兴趣。
关键词 非计算机专业 VISUAL basic程序设计 学习兴趣
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