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注射用奥美拉唑在注射前的抽配观察
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作者 李世帆 《中国医药指南》 2008年第23期127-127,共1页
注射用奥美拉唑抽配方法对药物的外观有较大的影响。
关键词 奥美拉唑 抽配
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高抽巷合理层位研究及分期配抽采空区瓦斯技术 被引量:4
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作者 暴雨 《能源与环保》 2018年第5期55-58,63,共5页
针对郭庄煤矿采空区和邻近层瓦斯大量涌入回采工作面造成的上隅角超限频繁的问题,利用顶板裂隙移动规律及岩石物理力学参数,确定了高抽巷的最佳布置层位,经在3316回采工作面试验表明:第2阶段高抽巷小幅度开启抽采瓦斯最大浓度9.4%,瓦斯... 针对郭庄煤矿采空区和邻近层瓦斯大量涌入回采工作面造成的上隅角超限频繁的问题,利用顶板裂隙移动规律及岩石物理力学参数,确定了高抽巷的最佳布置层位,经在3316回采工作面试验表明:第2阶段高抽巷小幅度开启抽采瓦斯最大浓度9.4%,瓦斯纯量4.65 m^3/min,上隅角瓦斯浓度能控制在0.5%以内;第3阶段高抽巷全面开启抽采瓦斯浓度稳定在3%~4%,高抽巷混合流量225.21m^3/min,纯流量8.11 m^3/min,上隅角瓦斯浓度能控制在0.4%以内。高抽巷分段配抽有效保障了工作面回采安全。 展开更多
关键词 分段 上隅角 瓦斯浓度
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高抽巷分期配抽采空区瓦斯技术
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作者 暴雨 《内蒙古煤炭经济》 2018年第4期104-105,共2页
针对郭庄煤矿采空区和邻近层瓦斯大量涌入回采工作面,造成上隅角超限频繁的问题,利用顶板裂隙移动规律及岩石物理力学参数确定了高抽巷的最佳布置层位,经在3316回采工作面试验表明:第二阶段高抽巷小幅度开启抽采瓦斯最大浓度9.4%,瓦斯纯... 针对郭庄煤矿采空区和邻近层瓦斯大量涌入回采工作面,造成上隅角超限频繁的问题,利用顶板裂隙移动规律及岩石物理力学参数确定了高抽巷的最佳布置层位,经在3316回采工作面试验表明:第二阶段高抽巷小幅度开启抽采瓦斯最大浓度9.4%,瓦斯纯量4.65m^3/min,上隅角瓦斯浓度能控制在0.5%以内;第三阶段高抽巷全面开启抽采瓦斯浓度稳定在3%~4%之间,高抽巷混合流量225.21m^3/min,纯流量8.11m^3/min,上隅角瓦斯浓度能控制在0.4%以内。 展开更多
关键词 分段 上隅角 瓦斯浓度
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掘进混合式通风合理抽压风筒口位置的探讨 被引量:20
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作者 幸大学 《矿业安全与环保》 北大核心 2005年第4期25-27,共3页
对混合式通风的前抽后压和前压后抽两种布置方法进行模拟实验,采用的发尘浓度分别为510mg/m3和230mg/m3,调节抽压风筒口至工作面的距离,对工作区和巷道的粉尘浓度进行测定。根据粉尘浓度的变化规律,同时结合风流状态,分析得出较合理的... 对混合式通风的前抽后压和前压后抽两种布置方法进行模拟实验,采用的发尘浓度分别为510mg/m3和230mg/m3,调节抽压风筒口至工作面的距离,对工作区和巷道的粉尘浓度进行测定。根据粉尘浓度的变化规律,同时结合风流状态,分析得出较合理的抽、压风筒口位置,并求出与巷道断面积的关系。 展开更多
关键词 混合式通风 风筒口位置 压风量 粉尘浓度
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不同通风参数对掘进工作面降温的影响 被引量:8
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作者 辛嵩 刘尚校 +1 位作者 张逍 朱晓镇 《煤矿安全》 CAS 北大核心 2020年第10期112-117,共6页
为了明确压风筒距离及抽、压风量配比对掘进工作面冷却的影响,建立了赵楼煤矿7302轨道巷机掘工作面1∶1等比例物理模型,运用AnsysCFD软件对压风管出风口与掘进巷道迎头端面之间的距离L_f(分别设为2.5、5、7.5、10 m)、抽风量和压风量配... 为了明确压风筒距离及抽、压风量配比对掘进工作面冷却的影响,建立了赵楼煤矿7302轨道巷机掘工作面1∶1等比例物理模型,运用AnsysCFD软件对压风管出风口与掘进巷道迎头端面之间的距离L_f(分别设为2.5、5、7.5、10 m)、抽风量和压风量配比B(B分别设为1、1.5、2)条件下的掘进工作面风流参数的影响进行数值模拟。结果表明:当Lf大于5 m时,工作区域的风流都能保持在0.3 m/s以上,随着Lf的增加,掘进迎头附近的涡流场变化加剧,当L_f=5 m,B=1.5时,巷道内工作区域平均温度27°C,长抽短压混合式通风系统可达到最佳的通风降温效果。将数值模拟结果应用到赵楼煤矿7302掘进工作面通风系统优化后,对工作面内多个断面上的测点进行风速、风温测量,实测风速与数值模拟结果平均相对误差10.07%,实测风温与数值模拟结果平均相对误差1.60%,数值模拟结果较为准确。 展开更多
关键词 掘进工作面 风比 降温 数值模拟 通风优化
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Distributed Sampling Measurement Model in a Large-Scale High-Speed IP Networks 被引量:1
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作者 龚俭 程光 《Journal of Southeast University(English Edition)》 EI CAS 2002年第1期40-45,共6页
The distributed passive measurement is an important technology for networkbehavior research. To achieve a consistent measurement, the same packets should be sampled atdistributed measurement points. And in order to es... The distributed passive measurement is an important technology for networkbehavior research. To achieve a consistent measurement, the same packets should be sampled atdistributed measurement points. And in order to estimate the character of traffic statistics, thetraffic sample should be random in statistics. A distributed samplingmask measurement model isintroduced to tackle the difficulty of measuring the full trace of high-speed networks. The keypoint of the model is to choose some bits that are suitable to be sampling mask. In the paper, thebit entropy and bit flow entropy of IP packet headers in CERNET backbone are analyzed, and we findthat the 16 bits of identification field in IP packet header are fit to the matching field ofsampling mask. Measurement traffic also can be used to analyze the statistical character ofmeasurement sample and the randomicity of the model. At the same time the experiment resultsindicate that the model has a good sampling performance. 展开更多
关键词 sampling measurement bit entropy matching field identification field
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High Performance Compressed Sampling for OFDM-UWB Systems 被引量:1
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作者 Lijun Ge Hua Zhang +1 位作者 Hui Guo Hong Wu 《China Communications》 SCIE CSCD 2017年第3期75-86,共12页
In order to solve the problem of high-speed sampling in OFDM based ultra wide band(UWB) systems, this paper first gives analysis on the applicability of existing compressed sampling methods. Then, on the basis of an e... In order to solve the problem of high-speed sampling in OFDM based ultra wide band(UWB) systems, this paper first gives analysis on the applicability of existing compressed sampling methods. Then, on the basis of an established segmented observation model, it presents an optimized parallel segmented compressed sampling(OPSCS) scheme based on Hadamard matrix. The orthogonal Hadamard matrix is adopted to construct the segmented measurement matrix with any dimensions, thus orthogonal or quasi-orthogonal multiplex observation sequences are obtained, and the restricted isometry property is improved. The optimized orthogonal matching pursuit algorithm is also used for the known sparsity avoiding iterative operation. Researches show that the proposed method can effectively reduce the sampling rate in OFDM-UWB systems, and also has a good ability of noise resisting that it achieves a high system performance better than the existing schemes of compressed sampling and even Nyquist rate sampling. 展开更多
关键词 ultra wide band OFDM compressed sampling observation sequence hadamard matrix OMP
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Product Vibrational State Distributions of F+CH_(3)OH Reaction on Full-Dimensional Accurate Potential Energy Surface
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作者 Meng Zhang Yongfa Zhu Jun Li 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期153-166,I0064,共15页
The hydrogen abstraction reaction of methanol with fluorine atoms can produce HF and CH_(3)O or CH_(2)OH radicals,which are important in the environment,combustion,radiation,and interstellar chemistry.In this work,the... The hydrogen abstraction reaction of methanol with fluorine atoms can produce HF and CH_(3)O or CH_(2)OH radicals,which are important in the environment,combustion,radiation,and interstellar chemistry.In this work,the dynamics of this typical reaction is investigated by the quasi-classical trajectory method based on a recently developed globally accurate full-dimensional potential energy surface.Particularly,the vibrational state distributions of the polyatomic products CH_(3)O and CH_(2)OH are determined by using the normal mode analysis method.It is found that CH_(3)O and CH_(2)OH are dominantly populated in the ground state when the reactants are at the ground ro-vibrational state.The OH stretching mode,torsional mode,H_(2)CO out-of-plane bending mode and their combination bands in the CH_(2)OH product can be effectively excited once the OH stretching mode of the reactant CH_(3)OH is excited to the first vibrationally excited state.Most of the available energy flows into the HF vibrational energy and the translational energy in both channels,while the radical products,CH_(3)O or CH_(2)OH,receive a small amount of energy,consistent with experiment,which is an indication of its spectator nature. 展开更多
关键词 Normal mode analysis Potential energy surface CH_(3)OH Product energy partitioning Hydrogen abstraction reaction
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Analysis of Methodology for the Application of Stratified Random Sampling with Optimum Allocation: The Case Study of Forest Bioenergy
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作者 M.N.Tsatiris 《Journal of Environmental Science and Engineering(A)》 2012年第1期82-91,共10页
In this paper, analysis of methodology was realized for the application of stratified random sampling with optimum allocation in the case of a subject of research which concerns the rural population and presents high ... In this paper, analysis of methodology was realized for the application of stratified random sampling with optimum allocation in the case of a subject of research which concerns the rural population and presents high differentiations among the three strata in which this population could be classified. The rural population of Evros Prefecture (Greece) with criterion the mean altitude of settlements was classified in three strata, the mountainous, semi-mountainous and fiat population for the estimation of mean consumption of forest fuelwood for covering of heating and cooking needs in households of these three strata. The analysis of this methodology includes: (1) the determination of total size of sample for entire the rural population and its allocation to the various strata; (2) the investigation of effectiveness of stratification with the technique of analysis of variance (One-Way ANOVA); (3) the conduct of sampling research with the realization of face-to-face interviews in selected households and (4) the control of forms of the questionnaire and the analysis of data by using the statistical package for social sciences, SPSS for Windows. All data for the analysis of this methodology and its practical application were taken by the pilot sampling which was realized in each stratum. Relative paper was not found by the review of literature. 展开更多
关键词 Analysis of methodology stratified random sampling with optimum allocation rural population forest bioenergy.
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SEMIAUTOMATIC BUILDING EXTRACTION FROM STEREO IMAGE PAIR BASED ON LINES GROUPING AND LEAST SQUARES MATCHING
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作者 ZHANG ZuxunHU XiangyunZHANG Jianqing 《Geo-Spatial Information Science》 2001年第4期49-55,共7页
The paper presents a general paradigm of semiautomatic building extraction from aerial stereo image pair.In the semiautomatic extraction system,the building model is defined by selected roof type through human-machine... The paper presents a general paradigm of semiautomatic building extraction from aerial stereo image pair.In the semiautomatic extraction system,the building model is defined by selected roof type through human-machine interface and input the approximation of area where the extracted building exists.Then under the knowledge of the roof type,low-level and mid-level processing including edge detection,straight line segments extraction and line segments grouping are used to establish the initial geometrical model of the roof-top.However,the initial geometrical model is not so accurate in geometry.To attain accurate results,a general least squares adjustment integrating the linear templates matching model with geometrical constraints in object-space is applied to refine the initial geometrical model.The adjustment model integrating the straight edge pattern and 3D constraints together is a well-studied optimal and anti-noise method.After gaining proper initial values,this adjustment model can flexibly process extraction of kinds of roof types by changing or assembling the geometrical constraints in object-space. 展开更多
关键词 building extraction GROUPING least squares matching object-space
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Changes of macromolecular organizations in nonjunctional sarcolemmas after cross-innervation──a study offast-and slow-twitch muscle fibres in rats
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作者 LU JIANLI TIEFENG ZHANG +2 位作者 FUJIN QU BEIHUA QIAN SHIKAI HUANG(Shanghai Institute of Physiology, Chinesc Academy of Scicnces, 320 Yue-Yang Road, Shanghai 200031, China) 《Cell Research》 SCIE CAS CSCD 1995年第2期143-154,共12页
The purpose of the present study was to analyse the changes of macromolecular organizations in nonjunctional sarcolemmas of different types of skeletal muscle fibres after cross-innervation. In normal rats the mean de... The purpose of the present study was to analyse the changes of macromolecular organizations in nonjunctional sarcolemmas of different types of skeletal muscle fibres after cross-innervation. In normal rats the mean density of square arrays (6 nm particles organized in orthogonal arrays) was 9.02/μm2 for the nonjunctional sarcolemmas of fast-twitch extensor digitorum longus (control EDL,CE) nuscle fibres and 0.34/μm2 for the nonjunctional sarcolemmas of slow-twitch soleus (control SOL, CS) muscle fibres. After cross-innervation between the fast-twitch EDL and slow-twitch SOL muscle fibres by slow and fast muscle merves respectively for three months, the mean density was 0.45/μm2 for the nonjunetional sarcolemmas of the operated-EDL (OE) and 8.3/μm2 for the nonjunctional sarcolemmas of the operated SOL (OS). This indicates that the cross-innervation causes a reciprocal transformation of the number and distribution of such macromolecular organizations in the electrically excitable nonjunctional sarcolemmas. 展开更多
关键词 SARCOLEMMA square array cross-innervation freeze-fracturing rat(Wistar)
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On the Conceptual Shift and Collocation Between Concreteness and Abstractness——Analysis of The Mill by a New Poet in China
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作者 LAI Peng 《Journal of Literature and Art Studies》 2016年第7期769-774,共6页
This is a poem review which analyzes The Mill that was written by a new poet in China, looking at it from the conceptual perspective. The conceptual shift and collocation between concreteness and abstractness enable h... This is a poem review which analyzes The Mill that was written by a new poet in China, looking at it from the conceptual perspective. The conceptual shift and collocation between concreteness and abstractness enable her poems to carry both linguistic power and emotional strength; the conceptual images created by her abstract thinking and unique perception make her poems achieve originality and readability; her conceptual self built by the use of first person pronouns is actually not that of a person but that of a personified mule who was indignant about its heavy workload yet unable to speak against its predestined destiny. Although suffering from brain paralysis, the poet is shown by this review to be a sensible manipulator of words, which reveal the unique beauty in her language and show the suppressed sadness in her heart. 展开更多
关键词 poem review conceptual shift conceptual collocation CONCRETENESS ABSTRACTNESS
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OPTIMAL ALLOCATION FOR ESTIMATING THE CORRELATION COEFFICIENT OF MORGENSTERN TYPE BIVARIATE EXPONENTIAL DISTRIBUTION BY RANKED SET SAMPLING WITH CONCOMITANT VARIABLE 被引量:1
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作者 XIE Minyu XIONG Ming WU Ming 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第2期249-260,共12页
Ranked set sample is applicable whenever ranking of a set of sample units can be done easily by a judgement method of the study variable or of the auxiliary variable. This paper considers ranked set sample based on th... Ranked set sample is applicable whenever ranking of a set of sample units can be done easily by a judgement method of the study variable or of the auxiliary variable. This paper considers ranked set sample based on the auxiliary variable X which is correlated with the study variable Y, where (X, Y) follows Morgenstern type bivariate exponential distribution. The authors discuss the optional allocation for unbiased estimators of the correlation coefficient p of the random variables X and Y when the auxiliary variable X is used for ranking the sample units and the study variable Y is measured for estimating the correlation coefficient. This paper first gives a class of unbiased estimators of p when the mean 0 of the study variable Y is known and obtains an essentially complete subclass of this class. Further, the optimal allocation of the unbiased estimators is found in this subclass and is proved to be Bayes, admissible, and minimax. Finally, the unbiased estimator of p under the optimal allocation in the case of known θ is reformed for estimating p in the case of unknown θ, and the reformed estimator is shown to be strongly consistent. 展开更多
关键词 Concomitants of order statistic Morgenstern type bivariate exponential distribution optimal allocation ranked set sample unbiased estimator.
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