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pep_pattern.Pl,搜索蛋白质序列模体的Perl脚本 被引量:3
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作者 李旭凯 彭良才 王令强 《华中农业大学学报》 CAS CSCD 北大核心 2014年第4期1-6,共6页
用Perl语言编写了一个pep_pattern.pl脚本,可从一组相关序列中搜索非常相似的序列片段,通过匹配所有可能的氨基酸片段的排列,统计每个匹配模体在序列中的出现频率和位置,搜索蛋白质序列中的2~4个多肽的模体。
关键词 pep—pattern pl Perl脚本 蛋白质序列 模体 排列
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基于S7-200 SMART PLC的PLS指令控制步进电机 被引量:1
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作者 李春晓 王鹏 程卫东 《电工技术》 2023年第4期4-6,共3页
步进电机的工作原理是将接收到的脉冲信号转化成与之相对应的角位移或直线位移,因此步进电机能够实现控制并应用于自动化生产中。基于西门子SMART系列给出一种通过人机交互(HMI)实时修改运动控制参数,实现控制PLC高速脉冲(PLS)输出的应... 步进电机的工作原理是将接收到的脉冲信号转化成与之相对应的角位移或直线位移,因此步进电机能够实现控制并应用于自动化生产中。基于西门子SMART系列给出一种通过人机交互(HMI)实时修改运动控制参数,实现控制PLC高速脉冲(PLS)输出的应用例程序。 展开更多
关键词 步进电机 高速脉冲 SMART plS plC
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Water Stress Early Detection of Eggplant Plants by Hyperspectral Fluorescence Spectroscopy
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作者 Amara Kamate Penetjiligué Adama Soro +2 位作者 Emma Georgina Zoro-Diama Kedro Sidiki Diomande Adjo Viviane Adohi-Krou 《Open Journal of Applied Sciences》 CAS 2023年第3期343-354,共12页
Water stress early detection is essential for precision farming to improve crop productivity and product quality. The methods usually used are destructive, long and expensive. In this work, we used hyperspectral chlor... Water stress early detection is essential for precision farming to improve crop productivity and product quality. The methods usually used are destructive, long and expensive. In this work, we used hyperspectral chlorophyll fluorescence technology as a rapid, non-destructive approach to detect the water deficiency of eggplant plants using their spectral footprint. So, an experiment was made on 54 eggplant plants subjected to three water treatments: normal irrigation (T<sub>100</sub>), intermediate irrigation (T<sub>50</sub>) and no irrigation (T<sub>0</sub>). The fluorescence spectra were acquired in vivo and in situ using a USB4000 spectrometer from Ocean optics. For the classification of the plants subjected to three water treatments, we used three pretreatments of the raw hyperspectral data in order to suppress the non-informative variability present in these spectra and to obtain robust models. These are the Savitzky-Golay smoothing (SG), the standard normal variable (SNV) and the first derivative of Savitzky-Golay (SG-D1). The preprocessed data were then subjected to two partial least squares discriminant analyses (PLS-DA): Hard PLS-DA and Soft PLS-DA. These statistical approaches are suitable for large samples as it reduces the dimensionality of the data but improves the accuracy of the prediction. The SG-D1 combined with the Soft PLS-DA gave the best discrimination of plants with scores of sensitivity, specificity and total efficiency respectively of 97.33%, 94% and 95% for calibration, 6 days after hydric stress induction. For the plants used for the prediction, the scores are 86%, 91% and 90% respectively. This study shows that hyperspectral chlorophyll fluorescence spectroscopy is a fast and non-destructive technology allowing early detection of water stress in eggplant plants. 展开更多
关键词 Chlorophyll Fluorescence EGGplANT Water Stress Water Deficiency plS-DA
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基于NIRS和Local PLS算法的堆肥关键参数实时动态分析 被引量:6
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作者 黄圆萍 沈广辉 +3 位作者 廖科科 吴亚蓝 韩鲁佳 杨增玲 《农业工程学报》 EI CAS CSCD 北大核心 2020年第13期195-202,共8页
为对不同堆肥工艺堆肥全过程关键参数进行实时动态分析,该研究以牛粪便和玉米秸秆为原料,进行规模化槽式和膜覆盖好氧堆肥,采集堆肥全过程样本,分析了2种堆肥技术堆肥全过程中含水率、有机质含量和碳氮比等关键参数的变化,并结合Local ... 为对不同堆肥工艺堆肥全过程关键参数进行实时动态分析,该研究以牛粪便和玉米秸秆为原料,进行规模化槽式和膜覆盖好氧堆肥,采集堆肥全过程样本,分析了2种堆肥技术堆肥全过程中含水率、有机质含量和碳氮比等关键参数的变化,并结合Local PLS算法建立了2种堆肥技术堆肥全过程中上述参数的通用速测模型,得出以下结果:1)2种主要工艺关键参数数值及变化规律均不同,且在整个堆肥过程中有显著性变化(P<0.05);2)所建立的Local PLS模型的RPD(Ratio of Prediction to Deviation)为4.47,RSD(Relative Standard Deviation)为3.37%,可达到很好的预测效果;有机质含量和碳氮比的R_P^2分别为0.74和0.77,RPD大于1.5,RSD小于10%,模型可用于定量预测;近红外预测值与实测值随堆肥时间的变化趋势具有较好的一致性,可实现规模化堆肥过程中关键参数的实时分析。 展开更多
关键词 近红外 堆肥 算法 过程分析 槽式堆肥 膜覆盖堆肥 关键参数 Local plS
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GKD-BASE PL/SQL引擎实现关键技术研究 被引量:2
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作者 唐扬 熊伟 +1 位作者 陈宏盛 景宁 《电子技术应用》 北大核心 2004年第8期21-23,共3页
在数据库管理系统GKD-BASE上设计并实现了兼容OraclePL/SQLV2.3语言规范的PL/SQL引擎,扩展了GKD-BASE过程处理功能。
关键词 GKD-BASE pl/SQL 符号表 游标 数据库
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利用Oracle PL/SQL Package实现Dispatcher设计模式
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作者 袁华强 肖鹏 《计算机工程与设计》 CSCD 北大核心 2005年第5期1339-1340,1348,共3页
Dispatcher设计模式可以使用各种技术来实现。以社会保险业务处理为基础,有效地利用ORACLEPL/SQLPac-kage语言及支撑环境对面向对象技术的支持,通过定义消息ID、传递消息ID、撰写处理函数、连接消息ID和处理函数来实现Dispatcher设计模... Dispatcher设计模式可以使用各种技术来实现。以社会保险业务处理为基础,有效地利用ORACLEPL/SQLPac-kage语言及支撑环境对面向对象技术的支持,通过定义消息ID、传递消息ID、撰写处理函数、连接消息ID和处理函数来实现Dispatcher设计模式,并且构造出能处理各项社会保险管理业务的Package组件。 展开更多
关键词 pl/SQL PACKAGE 组件技术 设计模式 Dispatcher设计
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利用ORACLE PL/SQL PACKAGE实现DISPATCHER设计模式 被引量:1
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作者 欧阳元东 《电脑学习》 2006年第1期39-40,共2页
以ORACLEPACKAGE语言及支撑环境为基础,有效地利用其对面向对象技术的支持,实现DISPATCHER设计模式。
关键词 pl/SQL PACKAGE 组件技术 DISPATCHER 设计模式
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Characterization of Uniform PL-convexity of Complex Banach Space by Functions with Two Variables
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作者 HUANG Hai jun,LIU Pei de (College of Mathematics and Computer Science, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第4期399-403,共5页
We give a new characterization ofq-uniform PL-convexity of complex Banach space by using the existence of a kind of functions with two variables and then prove a sharp weak (1, 1)-type inequality for analytic martinga... We give a new characterization ofq-uniform PL-convexity of complex Banach space by using the existence of a kind of functions with two variables and then prove a sharp weak (1, 1)-type inequality for analytic martingales with values in the Banach space. 展开更多
关键词 analytic martingale uniform pl CONVEXITY mean square operator
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ORACLE PL/SQL中的例外处理初探
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作者 秦亮曦 《计算机工程与应用》 CSCD 北大核心 1997年第8期1-3,共3页
本文对ORACLEPL/SQL的程序结构以及例外处理机制作了一个初步的探讨,并结合几个例子介绍了一些实用技巧。
关键词 ORACLE 数据库 pl/SQL 例外处理
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Innovation and Evaluation of Technology Acceptance Model (Tam) in S-Commerce: A Case of Social Media Platforms in Ghana
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作者 Peprah Rene Owusu Ennin Peter Asiedu +1 位作者 Jiangming Ji Francis Atta Sarpong 《Journal of Computer and Communications》 2022年第3期100-124,共25页
Electronic commerce is quickly increasing in several countries, most notably in developing countries. A new electronic-commerce segment known as social commerce has evolved due to the popularity of social media. Consu... Electronic commerce is quickly increasing in several countries, most notably in developing countries. A new electronic-commerce segment known as social commerce has evolved due to the popularity of social media. Consumer trust is important to social commerce success and impacts purchase choices. In modern times, majority of businesses have changed how from the traditional businesses and migrated to social commerce. Electronic commerce was the first of its sort, followed by social commerce, which conducted business via social networking platforms. Identifying the factors that influence social commerce use enables businesses to enhance those features and boost revenue. Thus, the purpose of this study was to examine how increased technology usage influences the social commerce activities of Ghanaian businessmen and women. A review of the literature resulted in the development of a conceptual model. Six hundred and twenty-five responses from Ghanaian enterprises and women who use e-commerce platforms were used to assess the conceptual approach. Partial Least Square Structural Equation Modeling (PLS SEM) was used to validate the model. The reliability and validity of the measuring apparatus were determined using measurement model analysis. To examine the model’s fit and assumptions, we used structural model analysis. Five hypotheses were supported by the structural model data. Effort Expectancy, Perceived Ease of Use, Performance Expectancy, Perceived Utility, and Trust were shown to be the most influential criteria affecting behavioral intention to use s-commerce in Ghana. The findings of this research have major significance for academics and practitioners of social trade. 展开更多
关键词 Technology Acceptance Model (TAM) Smart plS SEM Social Commerce Electronic Commerce
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Effects of microwave oxygen plasma treatments on microstructure and Ge-V photoluminescent properties of diamond particles
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作者 盛凌霄 陈成克 +2 位作者 蒋梅燕 李晓 胡晓君 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期489-494,共6页
The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and diso... The microstructure and Ge-V photoluminescent properties of diamond particles treated by microwave oxygen plasma are investigated.The results show that in the first 5 min of microwave plasma treatment,graphite and disordered carbon on the surface of the particles are etched away,so that diamond with regular crystal plane,smaller lattice stress,and better crystal quality is exposed,producing a Ge-V photoluminescence(PL)intensity 4 times stronger and PL peak FWHM(full width at half maximum)value of 6.6 nm smaller than the as-deposited sample.It is observed that the cycles of‘diamond is converted into graphite and disordered carbon,then the graphite and disordered carbon are etched’can occur with the treatment time further increasing.During these cycles,the particle surface alternately appears smooth and rough,corresponding to the strengthening and weakening of Ge-V PL intensity,respectively,while the PL intensity is always stronger than that of the as-deposited sample.The results suggest that not only graphite but also disordered carbon weakens the Ge-V PL intensity.Our study provides a feasible way of enhancing the Ge-V PL properties and effectively controlling the surface morphology of diamond particle. 展开更多
关键词 diamond particles Ge-V center microwave oxygen plasma treatment pl enhancement
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GKD-Base PL/SQL存储过程的设计与实现 被引量:1
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作者 高朝瑞 熊伟 +1 位作者 吴秋云 陈宏盛 《计算机工程与应用》 CSCD 北大核心 2005年第10期162-164,214,共4页
存储过程作为一种高效访问数据库的机制,是现代数据库系统的重要特征。该文兼容OraclePL/SQLV2.3语言规范,在数据库管理系统GKD-BasePL/SQL引擎上,采用语法树表示存储过程的中间代码,并设计了函数管理器。从而在GKD-Base上实现了有效的... 存储过程作为一种高效访问数据库的机制,是现代数据库系统的重要特征。该文兼容OraclePL/SQLV2.3语言规范,在数据库管理系统GKD-BasePL/SQL引擎上,采用语法树表示存储过程的中间代码,并设计了函数管理器。从而在GKD-Base上实现了有效的存储过程编译、存储、调用和执行机制。 展开更多
关键词 pl/SQL 存储过程 符号表 函数管理器
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第八讲 PL/SQL语言的条件、循环及异常控制语句
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作者 王兰成 王兰言 《核工业自动化》 2003年第1期38-48,共11页
关键词 pl/SQL语言 条件控制语句 循环控制语句 异常控制语句
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UNIVIB PLS 326型震源驱动控制原理及典型故障分析
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作者 孔志勇 孙永峰 孔春超 《物探装备》 2021年第1期53-56,63,共5页
本文对INOVA公司生产的UNIVIB PLS 326型可控震源驱动控制电路及驱动液压控制原理进行了详细介绍,并对其典型的驱动故障做实例分析,总结积累经验,旨在为野外项目解决该型号震源驱动故障提供借鉴。
关键词 UNIVIB plS 326 可控震源 驱动电路 故障分析
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第七讲 PL/SQL语言及其基本使用
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作者 王兰成 郑晨阳 敖毅 《核工业自动化》 2003年第1期27-37,共11页
从ORACLE6系统开始提供了一个称作PL/SQL的过程处理语言,其过程、函数、包等程序块包括了一整套的数据类型、条件结构、循环结构和异常处理结构的处理。
关键词 ORACLE6系统 pl/SQL 过程处理语言 数据类型 条件结构 循环结构 异常处理结构
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第九讲 PL/SQL语言对数据库的交互作用
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作者 王兰成 《核工业自动化》 2003年第2期30-38,共9页
关键词 pl/SQL语言 数据库 交互作用 游标 DML语句 变量 程序员
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GKD-Base PL/SQL存储函数实现的关键技术研究 被引量:1
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作者 高朝瑞 熊伟 +1 位作者 陈宏盛 翟玉人 《电子技术应用》 北大核心 2005年第1期8-11,共4页
介绍具有自主知识产权的某安全数据库管理系统GKD-Base的PL/SQL引擎,基于该引擎研究GKD-Base存储函数机制实现的关键技术。设计了函数管理器和执行状态堆栈,通过语法树表示存储函数编译后生成的中间代码,并解决了中间代码的执行问题。... 介绍具有自主知识产权的某安全数据库管理系统GKD-Base的PL/SQL引擎,基于该引擎研究GKD-Base存储函数机制实现的关键技术。设计了函数管理器和执行状态堆栈,通过语法树表示存储函数编译后生成的中间代码,并解决了中间代码的执行问题。最后实现了IN、OUT、INOUT三种参数模式函数的参数传递机制。 展开更多
关键词 pl/SQL 中间代码 存储 堆栈 参数传递 语法树 管理器 函数 模式 机制
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X-Base PL/SQL异常处理的设计与实现
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作者 石文渊 阳国贵 +1 位作者 廖巍 吴妍 《计算机工程》 EI CAS CSCD 北大核心 2006年第15期72-74,共3页
X-Base PL/SQL是一种过程式数据库编程语言,常用于数据库服务器端应用程序的开发。该文讨论了X-Base PL/SQL引擎中异常处理模块的设计思想和实现技术。鉴于Oracle数据库管理系统是数据库产品事实上的标准,还有其在全球的广泛应用,X-Base... X-Base PL/SQL是一种过程式数据库编程语言,常用于数据库服务器端应用程序的开发。该文讨论了X-Base PL/SQL引擎中异常处理模块的设计思想和实现技术。鉴于Oracle数据库管理系统是数据库产品事实上的标准,还有其在全球的广泛应用,X-Base PL/SQL需要兼容Oracle PL/SQL 8i的异常处理机制。 展开更多
关键词 符号表 异常处理器 pl/SQL引擎 异常传播
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Evaluation of the Customer Satisfaction Index for Wellhead Blowout Preventers of China’s Petroleum Industry——A new method based on PLS 被引量:8
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作者 Zhang Peng Hu Qiguo +1 位作者 Han Xia Zhang Bin 《Petroleum Science》 SCIE CAS CSCD 2005年第3期54-64,共11页
This paper establishes an evaluation model of the customer satisfaction index for the wellhead blowout preventers of China's petroleum industry based on evaluation models of the customer satisfaction index at home an... This paper establishes an evaluation model of the customer satisfaction index for the wellhead blowout preventers of China's petroleum industry based on evaluation models of the customer satisfaction index at home and aboard, and by considering the consuming situation in China and the features of the China's petroleum industry. For the existence of: (1) multiple correlations among the factors in the model; (2) the variables need to be explained, but that are hard to observe; (3) the customer satisfaction degree of observation variables appears the shape of skewness or two or three peaks, the correlations between the satisfaction index and its factors cannot be described by common multiple regression. This paper uses a partial least squares (PLS) method based on principal components and typical correlative analysis to solve the problem. When PLS is used in the model of the customer satisfaction index of the wellhead blowout preventers, the latent variables and the explanation degree coefficient of the manifest variable to the corresponding latent variables are estimated by PLS path analysis, and the influencing coefficient among the latent variables in the model is estimated by PLS regression analysis. PLS is also be used to calculate and analyze the model and disclose the correlations among the structural variables as well as the correlation between structural variables and its corresponding observation variables, evaluating results of which provide useful information for petroleum industry to improve the product quality and to the enhancement of the customer satisfaction to the product. 展开更多
关键词 Customer satisfaction index evaluation model plS wellhead blowout preventer
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PID控制器在S7-300 PLC中的实现及应用 被引量:7
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作者 苏涛 曹玉波 《吉林化工学院学报》 CAS 2012年第7期38-40,共3页
PID控制算法在流程工业自动控制系统中具有广泛的应用.本文分析了PID控制器的基本工作原理,研究了西门子S7-300 PLC中PID控制器算法和逻辑,并以某蒸汽加热系统为研究对象,利用Step7提供的PID功能块,在S7-300 PLC中实现了加热器温度自动... PID控制算法在流程工业自动控制系统中具有广泛的应用.本文分析了PID控制器的基本工作原理,研究了西门子S7-300 PLC中PID控制器算法和逻辑,并以某蒸汽加热系统为研究对象,利用Step7提供的PID功能块,在S7-300 PLC中实现了加热器温度自动控制,并在实际应用中取得了良好的控制效果. 展开更多
关键词 PID控制器 S7-300 plC 自动控制
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