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Search Results: 1 - 10 of 213507 matches for " 刘 姣 "
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河北省安国药田和粮田土壤有效氮空间分布特征
,文科
华北农学报 , 2014, DOI: 10.7668/hbnxb.2014.S1.054
Abstract: 为研究安国市药田和粮田土壤中有效氮含量累积及分布特征,分析了河北省安国市药田和粮田不同土壤深度中有效氮的含量。结果表明,药田和粮田土壤中有效氮含量在各地块间差异较大;药田和粮田土壤中有效氮含量随土层深度的增加而减低,差异极显著(P<0.01);药田0~20,20~40,40~60cm土壤中有效氮含量分别为39.42,24.02,16.07mg/kg,粮田0~20,20~40,40~60cm土壤中有效氮含量分别为37.37,22.88,13.20mg/kg,粮田土壤中有效氮含量略低于药田土壤。按照第2次全国土壤普查确定的土壤肥力分级标准可知,药田和粮田中有效氮含量处于五级或六级水平,肥力很低。由此说明,药田和粮田土壤的供氮水平相当,但土壤氮素肥力较低,生产中应多采取有机肥与无机肥配施提高地力。
安国市药田与粮田土壤有效磷累积特征
,文科
华北农学报 , 2013, DOI: 10.7668/hbnxb.2013.S1.066
Abstract: 通过田间调查与室内化学分析相结合的方法,研究安国市药田与粮田不同深度土壤中有效磷累计特征。调查结果显示,在0~20,20~40,40~60,0~60cm土壤深度上,药田土壤中有效磷的平均值分别是36.43,16.09,9.05,20.54mg?kg,粮田土壤中有效磷的平均含量是22.23,12.19,7.82,13.98mg?kg。t检验结果显示,药田和粮田在不同土壤深度上有效磷含量差异显著且在0~20cm土壤深度上药田有效磷含量显著高于粮田土壤,然而在20~40,40~60,0~60cm土壤深度上药田和粮田土壤中有效磷含量差异不显著。总之,药田和粮田在0~20,20~40,40~60cm的土壤深度上,随着土壤深度的加深,土壤中有效磷含量降低,药田耕层土壤中有效磷含量显著高于粮田耕层土壤有效磷含量。
基于HSV和MB_LBP特征的级联Adaboost车牌检测算法
Detection Algorithm of Cascaded Adaboost License Plate Based on HSV color model and MB_LBP Features

马永杰,李欢,
- , 2018,
Abstract: 车牌检测作为车牌识别系统中的重要环节,直接影响着车牌识别的准确度。为提高车牌的检测率和检测速度,提出了一种基于HSV颜色模型和多分块局部二值模式(MB_LBP)特征的级联Adaboost车牌检测方法。首先将车牌图像由RGB颜色空间转换到HSV颜色空间,统计蓝色像素占车牌总像素的比例,来构建第一层强分类器;其次对车牌字符样本提取MB_LBP特征,利用Adaboost分类器训练方法进行特征选择及分类器训练,最后利用Cascade结构检测法形成一种新的车牌检测算法。实验表明,本文算法有效的提高了车牌检测率和检测速度。
License plate detection is an important part of the license plate recognition system, which deeply affects the accuracy of license plate recognition. A method for cascade adaboost license plate detection based on HSV color model and multi-block local binary patterns (MB_LBP) is presented to realize fast and accurate license plate detection and recognition. Firstly, the license plate image is transformed from RGB color space to HSV color space, and the ratio of the blue pixels to the total pixels of the license plate is counted to construct the first class strong classifier. Then, the MB_LBP feature is extracted from the license plate character samples, and the feature selection and the classifier training are carried out by using the Adaboost classifier training method. Finally, a new license plate detection algorithm is formed by using the Cascade structure detection method. Experiments results show that the license plate detector improves the detection rate and the detection speed
中西医结合保守治疗输卵管异位妊娠

中国中医药信息杂志 , 2008,
Abstract:
湖南创意休闲农业发展战略研究
军?,
中国农业资源与区划 , 2013, DOI: 10.7621/cjarrp.1005-9121.20130425
Abstract: 在科学阐述湖南创意休闲农业发展成就的基础上,确定了湖南创意休闲农业的指导思想与目标,并将湖南创意休闲农业的总体布局规划成“一核心两环三板块”:其中“一核心”指长株潭城市群都市型创意休闲农业核心,“两环”指洞庭湖湿地田园风光创意休闲农业环和四大山脉(武陵山脉、雪峰山脉、南岭山脉、罗霄山脉)森林氧吧-康体养生创意休闲农业环,“三板块”指湘西民俗风情山水田园创意休闲农业板块、湘中南湖湘文化创意休闲农业板块、红色乡村旅游创意休闲农业板块。
响应面优化南极磷虾蛋白酶解工艺及蛋白肽组分分析

- , 2019, DOI: 10.13982/j.mfst.1673-9078.2019.1.021
Abstract: 以南极磷虾蛋白酶解液中的氨基氮含量为指标,采用甲醛电位滴定法测定胰蛋白酶、木瓜蛋白酶、碱性蛋白酶、胃蛋白酶、风味蛋白酶、枯草杆菌蛋白酶6种生物酶在其最适酶解条件下对南极磷虾蛋白酶解效果,筛选出酶解南极磷虾蛋白最佳生物酶。在单因素试验基础上,以酶解液中氨基氮含量为响应值,选择酶解温度、时间、pH为自变量,通过三因素三水平Box-Bohnken响应面分析法对筛选出来的生物酶解工艺进行优化。在优化酶解工艺的基础上,利用SDS-PAGE凝胶电泳方法分析南极磷虾酶解蛋白肽及南极磷虾蛋白的分子量分布范围。结果表明:胰蛋白酶为酶解南极磷虾蛋白的理想蛋白酶;响应面分析法建立二次多项回归方程:Y=51.07-0.83A+1.72B-2.06C+0.25AC+1.15BC-3.06A2-2.77B2-3.69C2,模型p<0.0001,而失拟项p>0.05,表明模型极显著且比较稳定,通过模型分析得最佳条件:酶解温度44.48 ℃、酶解时间8.52 h、pH 7.88,考虑实际应用可行性,我们在酶解温度45.0 ℃、酶解时间8.5 h,pH 7.9条件下实验得到的氨基氮含量为50.96±1.07 mg/g,与理论预测值51.57 mg/g基本一致。通过电泳分析得到南极磷虾蛋白分子量范围在15 ku以上,主要集中分子量范围为15 ku~45 ku;胰蛋白酶解多肽分子量在25 ku以下,主要分子量分布在5 ku以下。
The amino nitrogen content in the antarctic krill hydrolysate was used as an indicator. The hydrolysis results of trypsin, papain, alkaline protease, pepsin, flavor protease and subtilisin were evaluated by formaldehyde potentiometric titration. The enzymatic hydrolysis of Antarctic krill protein was optimized for the enzymatic hydrolysis of Antarctic krill. On the basis of single factor experiment, the amino acid content in the enzymatic hydrolysate was used as the response value, and the enzymatic hydrolysis temperature, time and pH were selected as independent variables. The three-factor and three-level Box-Bohnken response surface analysis method was used to screen the bio-enzymatic solution. The process is optimized. Based on the optimized enzymatic hydrolysis process, the molecular weight distribution range of Antarctic krill enzymatic protein peptide and Antarctic krill protein was analyzed by SDS-PAGE gel electrophoresis. The results showed that trypsin was the ideal protease for enzymatic hydrolysis of Antarctic krill protein; the response surface analysis method was used to establish a quadratic multiple regression equation: Y=51.07-0.83A+1.72B-2.06C+0.25AC+1.15BC-3.06A2-2.77B2-3.69C2, the model p<0.0001, and the missing term p>0.05, indicating that the model is extremely significant and stable, the best condition obtained by model analysis is: Enzymatic hydrolysis temperature was 44.48 ℃, the enzymatic hydrolysis time was 8.52 h, and the pH was 7.88. Considering the practical application feasibility, the amino nitrogen content of the experiment was 50.96±1.07 mg/g under the conditions of enzymatic hydrolysis temperature of 45.0 ℃, hydrolysis time of 8.5 h and pH 7.9, which is basically consistent with the theoretical prediction value of 51.57 mg/g. The molecular weight of Antarctic krill protein was over 15 ku by electrophoresis analysis, and the main molecular weight range was 15 ku~45 ku. The molecular weight of trypsin
燃气内燃机冷热电联产系统的技术经济性分析
Techno-Economic Analysis of CCHP System Based on Gas Internal Combustion Engine
 [PDF]

胡雪, , 廖胜明
Sustainable Energy (SE) , 2016, DOI: 10.12677/SE.2016.61001
Abstract:
本文针对分布式冷热电联产系统(CCHP)在市场化推广中的计费方式和能源定价等经济性问题,建立了内燃机冷热电联产系统的热力学模型,并确立了以年折算费用、年净收益、投资收益率为基础的技术经济评价体系。以长沙某大型公建的能源站三联供方案为例(额定制冷量23,098 kW,制热量16,445 kW,发电量2320 kW),选取制冷(热)量相同的直燃分产方案以及常规分产方案作为参照,基于协商式交易模式下的冷热电计费方式,综合比较了三种方案的各项经济性指标,并从投资方与用户方的利益出发,将天然气价、冷热电价与联产方案经济性指标的关系做了敏感性分析。本文研究结果为冷热电联产方案的市场化推广应用提供了重要参考依据。
To analyze the problem of billing way and energy pricing in market promotion of distributed combined cooling, heating and power system (CCHP), a thermodynamic model of the typical CCHP based internal combustion engine is established, and the average annual cost, net income and rate of return on investment are selected as the economy evaluation index in this paper. Based on the billing way of negotiated transaction mode, the CCHP system (rated refrigerating capacity 23,098 kW, heating capacity 16,445 kW, generating capacity 2320 kW) of a large public building in Changsha is taken as an example, and the direct-fired systems and conventional production systems of the same rated refrigerating (heating) capacity are proposed as alternative schemes to compare the techno-economic characteristics. Then based on the interests of the investors and user, the sensitivity analysis about gas prices, heat prices and electricity prices was executed to find its influences on the economy evaluation index of CCHP and conventional production systems. The results of this study provide an important reference for the development and application of CCHP system.
Qualitative Preference Decision and Reasoning of Consistency for CP-nets
CP-nets的定性偏好决策及一致性推理

孙雪,惊雷
计算机科学 , 2013,
Abstract: CP-nets (condition preference networks) is a simple and intuitive graphical tool for representing conditional ceteris paribus (all other things being equal) preference statements over the values of a set of variables, and it suits mul- tiple attributes qualitative decision making under incomplete preference information situation especially. Firstly,by con- structing induced graph of CP-nets and studying its properties, it was found that the nature of strong dominance testing is accessibility between vertices on the induced graph. So the problem of strong dominance testing with respect to bina- ry-valued CP-nets is solved by DFS algorithm. Secondly, the consistency for CP-nets was studied. The theorems and properties on consistency were given separately from the perspective of acyclic CP-nets and cyclic CP-nets. In particu- lar, three methods on judgment of consistency were proposed. All these can be seen as the improvement and refinement of I3outilier's related works.
基于表决策略的CP-Nets可满足性序列的聚合
孙雪,惊雷
模式识别与人工智能 , 2013,
Abstract: 条件偏好网(CP-Nets)的可满足性序列是由决策者的偏好信息得到的一个关于所有配置的排序表,其中偏好关系具有不完备性和传递性.主要分析借鉴传统的表决策略来实现CP-Nets的可满足性序列的聚合的可行性,介绍“少数服从多数”和“与位置相关”策略在CP-Nets的可满足性序列的聚合的具体实现并进行性能分析.实现传统表决系统的一个从完备到非完备的推广应用.
SEC-DED海明校验码算法研究及其FPGA实现
何秉,
中南民族大学学报(自然科学版) , 2012,
Abstract: 采用Multisim 11实现了SEC-DED海明码的编码、译码和纠错电路,并给出其相应时序仿真波形图.结果表明:其功能能满足SEC-DED的需要,为FPGA快速准确实现SEC-DED校验码提供了一种占用资源少、校验可靠高速的方案.
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