期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
低位硬膜外阻滞致麻醉平面过广4例分析
1
作者 黄新华 张洁 +1 位作者 王茹华 潘云 《海峡药学》 2010年第12期308-309,共2页
探讨低位硬膜外阻滞导致麻醉平在过广的原因及预防及处理措施。将我院自2000年至2009年发生的4例低位硬膜外麻醉引起异常广泛阻滞的患者作回顾性分析调查,对麻醉操作、麻醉管理,术中的预防与处理措施作出分析总结。4例患者麻醉平面至T1... 探讨低位硬膜外阻滞导致麻醉平在过广的原因及预防及处理措施。将我院自2000年至2009年发生的4例低位硬膜外麻醉引起异常广泛阻滞的患者作回顾性分析调查,对麻醉操作、麻醉管理,术中的预防与处理措施作出分析总结。4例患者麻醉平面至T1或T2,血压急剧下降,呼吸困难,经对症处理后,呼吸循环稳定,送麻醉复苏室待麻醉平面消退至T6以下,自主呼吸和循环稳定后送回普通病房,随访无异常。对于异常广泛阻滞,我们在临床工作中必须加以预防和重视。首先,硬膜外穿刺动作一定要轻柔;其次,硬膜外给药一定要使用试验量和分次分期给药,注药后要及时测麻醉平面,严密观察患者的情况;第三,发生异常广泛阻滞时,处理原则是采取各种措施维持呼吸和循环功能的稳定。 展开更多
关键词 硬膜外阻滞 低位 麻醉平面 过广 平发症
下载PDF
An Extended Birth-Death Processes with Catastrophes——Stochastically Monotone, Feller and Symmetric Properties
2
作者 吴群英 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期36-42,共7页
A new structure with the special property that catastrophes is imposed to ordinary Birth_Death processes is considered. The necessary and sufficient conditions of stochastically monotone, Feller and symmetric properti... A new structure with the special property that catastrophes is imposed to ordinary Birth_Death processes is considered. The necessary and sufficient conditions of stochastically monotone, Feller and symmetric properties for the extended birth_death processes with catastrophes are obtained. 展开更多
关键词 extended birth_death process Q _process stochastic monotonicity Feller property symmetric property
下载PDF
Progressive failure processes of reinforced slopes based on general particle dynamic method 被引量:3
3
作者 赵毅 周小平 钱七虎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期4049-4055,共7页
In order to resolve grid distortions in finite element method(FEM), the meshless numerical method which is called general particle dynamics(GPD) was presented to simulate the large deformation and failure of geomateri... In order to resolve grid distortions in finite element method(FEM), the meshless numerical method which is called general particle dynamics(GPD) was presented to simulate the large deformation and failure of geomaterials. The Mohr-Coulomb strength criterion was implemented into the code to describe the elasto-brittle behaviours of geomaterials while the solid-structure(reinforcing pile) interaction was simulated as an elasto-brittle material. The Weibull statistical approach was applied to describing the heterogeneity of geomaterials. As an application of general particle dynamics to slopes, the interaction between the slopes and the reinforcing pile was modelled. The contact between the geomaterials and the reinforcing pile was modelled by using the coupling condition associated with a Lennard-Jones repulsive force. The safety factor, corresponding to the minimum shear strength reduction factor "R", was obtained, and the slip surface of the slope was determined. The numerical results are in good agreement with those obtained from limit equilibrium method and finite element method. It indicates that the proposed geomaterial-structure interaction algorithm works well in the GPD framework. 展开更多
关键词 general particle dynamic algorithm(GPD) slope stability progressive failure process geomaterial-structure interaction
下载PDF
Modeling and Fault Monitoring of Bioprocess Using Generalized Additive Models (GAMs) and Bootstrap
4
作者 郑蓉建 周林成 潘丰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1180-1183,共4页
Fault monitoring of bioprocess is important to ensure safety of a reactor and maintain high quality of products. It is difficult to build an accurate mechanistic model for a bioprocess, so fault monitoring based on ri... Fault monitoring of bioprocess is important to ensure safety of a reactor and maintain high quality of products. It is difficult to build an accurate mechanistic model for a bioprocess, so fault monitoring based on rich historical or online database is an effective way. A group of data based on bootstrap method could be resampling stochastically, improving generalization capability of model. In this paper, online fault monitoring of generalized additive models (GAMs) combining with bootstrap is proposed for glutamate fermentation process. GAMs and bootstrap are first used to decide confidence interval based on the online and off-line normal sampled data from glutamate fermentation experiments. Then GAMs are used to online fault monitoring for time, dissolved oxygen, oxygen uptake rate, and carbon dioxide evolution rate. The method can provide accurate fault alarm online and is helpful to provide useful information for removing fault and abnormal phenomena in the fermentation. 展开更多
关键词 bioprocess fault monitoring generalized additive model glutamic acid fermentation BOOTSTRAP MODELING
下载PDF
Assessment of Model Predictive Control Performance Criteria 被引量:1
5
作者 Rafael Lopes Duarte-Barros Song Won Park 《Journal of Chemistry and Chemical Engineering》 2015年第2期127-135,共9页
The current highly competitive environment has driven industries to operate with increasingly restricted profit margins. Thus, it is imperative to optimize production processes. Faced with this scenario, multivariable... The current highly competitive environment has driven industries to operate with increasingly restricted profit margins. Thus, it is imperative to optimize production processes. Faced with this scenario, multivariable predictive control of processes has been presented as a powerful alternative to achieve these goals. Moreover, the rationale for implementation of advanced control and subsequent analysis of its post-match performance also focus on the benefits that this tool brings to the plant. It is therefore essential to establish a methodology for analysis, based on clear and measurable criteria. Currently, there are different methodologies available in the market to assist with such analysis. These tools can have a quantitative or qualitative focus. The aim of this study is to evaluate three of the best current main performance assessment technologies: Minimum Variance Control-Harris Index; Statistical Process Control (Cp and Cpk); and the Qin and Yu Index. These indexes were studied for an alumina plant controlled by three MPC (model predictive control) algorithms (GPC (generalized predictive control), RMPCT (robust multivariable predictive control technology) and ESSMPC (extended state space model predictive controller)) with different results. 展开更多
关键词 Predictive controller performance minimum variance CAPABILITY MPC GPC ESSMPC (extended state space model predictive controller).
下载PDF
Generalized Sampling Series Approximation of Random Signals from Local Averages
6
作者 宋占杰 何改云 +1 位作者 叶培新 杨德运 《Transactions of Tianjin University》 EI CAS 2007年第1期8-11,共4页
Signals are often of random character since they cannot bear any information if they are predictable for any time t, they are usually modelled as stationary random processes .On the other hand, because of the inertia ... Signals are often of random character since they cannot bear any information if they are predictable for any time t, they are usually modelled as stationary random processes .On the other hand, because of the inertia of the measurement apparatus, measured sampled values obtained in practice may not be the precise value of the signal X(t) at time tk (k∈Z), but only local averages of X(t) near tk. In this paper, it is presented that a wide (or weak ) sense stationary stochastic process can be approximated by generalized sampling series with local average samples. 展开更多
关键词 stochastic processes local averages generalized sampling series
下载PDF
News Genre Strategy: Comparing Agendas and Frames in The Daily Show and ABC Worm News
7
作者 Keith J. Zukas 《Journalism and Mass Communication》 2012年第2期399-411,共13页
Contemporary journalism scholars have taken important steps to identify and categorize emerging styles of news programing in the 21st Century (Entman, 2004; Holbert, 2005; Kovach & Rosenstiel, 2010). This study exp... Contemporary journalism scholars have taken important steps to identify and categorize emerging styles of news programing in the 21st Century (Entman, 2004; Holbert, 2005; Kovach & Rosenstiel, 2010). This study explores how soft news programs function in agenda setting processes and contribute to the sociological framing of political issues. It compares news agenda topics and frames between ABC Worm News with Charles Gibson and The Daily Show with Jon Stewart over the months prior to the determination of the Democrat and Republican 2008 presidential nominees. Results show that both programs contained similar amounts of top stories, main actors, and story problems, confirming similar agenda setting functions. Framing comparisons showed that in election coverage ABC Worm News had significantly more strategy frames than The Daily Show. The Daily Show contained significantly more responsibility and morality frames than ABC Worm News, providing an ethical viewpoint. These findings reveal that the news programs are similar in coverage of the top stories on each day's agenda, but that they are presented differently through framing decisions. This provides insight into agenda setting of election topics and highlights the potential for framing effects in different genres of journalism as the soft news frontier expands traditional definitions of political journalism. 展开更多
关键词 agenda setting election coverage FRAMING political journalism soft news
下载PDF
Efficacy of Trichogramma evanescens and Bacillus thuringiensis kurstaki to Control Lesser Date Moth Batrachedra amydraula Merck
8
作者 Hussain Fadhil Alrubeai Bassim Shehab Hamad +2 位作者 Ahmed Mushtaq Abdullatif Hani Zair Ali Ahmed Abed 《Journal of Agricultural Science and Technology(B)》 2014年第4期281-284,共4页
Efficacy of the egg parasitoid, Trichogramma evanescens and the bio-pesticide bacteria, Bacillus thuringiensis kurstaki (Btk) in reduction of lesser date moth, Batrachedra amydraula infestations were studied during ... Efficacy of the egg parasitoid, Trichogramma evanescens and the bio-pesticide bacteria, Bacillus thuringiensis kurstaki (Btk) in reduction of lesser date moth, Batrachedra amydraula infestations were studied during seasons of 2011 and 2012. The result of 2011 showed that the release of egg parasitoid by rate of 500 and 1,000 parasitoids/palm tree achieved 55.06% and 67.45% reduction in infestation percentage, respectively. Meanwhile high reduction in infestation was achieved by Btk (78.65%) at dose rate of 6 g Btk powder/kg talc powder. The result of 2012 showed that the highest control efficacy (58.78%) was achieved at the first time of the control process, using Btk at dose rate of 6 g/kg talc powder. This result was not different significantly from the release of egg parasitoid by rate of 1,000 parasitoids/palm tree which achieved 53% reduction in infestation percentage. At the second time (after one week from the first application), the efficacy of Btk at dose rate of 6g/kg talc powder was increased to 78.78%, which differ significantly with the release of egg parasitoid by the same rate of 1,000 parasitoids/palm tree, having 61.79% efficacy. Reapplication of the control method achieved an increase in efficacy of the control agents, such increase was significant for both the release of the parasitoid at rate of 1,000/palm tree and for Btk at a dose of 6 g/kg talc powder. 展开更多
关键词 Lesser date moth Batrachedra amydraula Trichogramma evanescens Btk.
下载PDF
Bitmap lattice index in road networks
9
作者 Doohee Song Keun-Ho Lee Kwangjin Park 《Journal of Central South University》 SCIE EI CAS 2014年第10期3856-3863,共8页
A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a... A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a server's workload increases as the query request increases when a server sends a client information. To solve this problem, we propose the BLI. The BLI denotes an object and a node as 0 and 1 in the Hilbert curve(HC) map. The BLI can identify the position of a node and an object through bit information; it can also reduce the broadcasting frequency of a server by reducing the size of the index, thereby decreasing the access latency and query processing times. Moreover, the BLI is highly effective for data filtering, as it can identify the positions of both an object and a node. In a road network, if filtering is done via the Euclidean distance, it may result in an error. To prevent this, we add another validation procedure. The experiment is conducted by applying the BLI to kNN query, and the technique is assessed by a performance evaluation experiment. 展开更多
关键词 road network wireless broadcast spatial query bitmap lattice index(BLI)
下载PDF
STUDY ON THE RELATIONSHIP BETWEEN WORKING MEMORY AND EFL LISTENING COMPREHENSION 被引量:7
10
作者 顾姗姗 王同顺 《Chinese Journal of Applied Linguistics》 2007年第6期46-56,127,共12页
The present study intends to investigate the effect of working memory on listening process and its relationship with listening comprehension.The results indicate that working memory is an effective predictor for EFL l... The present study intends to investigate the effect of working memory on listening process and its relationship with listening comprehension.The results indicate that working memory is an effective predictor for EFL listening comprehension,i.e.learners with larger working memory capacity are more likely to have better abilities in listening comprehension,and that although L1 working memory span is significantly correlated with L2 working memory span,L2 working memory span plays a more effective role in differentiating learners' EFL listening comprehension.Additionally,this study provides some pedagogical implications on EFL teaching. 展开更多
关键词 working memory working memory capacity working memory span listening comprehension listening process
原文传递
Entransy dissipation minimization for generalized heat exchange processes 被引量:13
11
作者 XIA ShaoJun 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第10期1507-1516,共10页
This paper investigates the MED (Minimum Entransy Dissipation) optimization of heat transfer processes with the generalized heat transfer law q ∝ (A(T^n))m. For the fixed amount of heat transfer, the optimal te... This paper investigates the MED (Minimum Entransy Dissipation) optimization of heat transfer processes with the generalized heat transfer law q ∝ (A(T^n))m. For the fixed amount of heat transfer, the optimal temperature paths for the MED are obtained The results show that the strategy of the MED with generalized convective law q ∝ (△T)^m is that the temperature difference keeps constant, which is in accordance with the famous temperature-difference-field uniformity principle, while the strategy of the MED with linear phenomenological law q ∝ A(T^-1) is that the temperature ratio keeps constant. For special cases with Dulong-Petit law q ∝ (△T)^1.25 and an imaginary complex law q ∝ (△(T^4))^1.25, numerical examples are provided and further compared with the strategies of the MEG (Minimum Entropy Generation), CHF (Constant Heat Flux) and CRT (Constant Reservoir Temperature) operations. Besides, influences of the change of the heat transfer amount on the optimization results with various heat resistance models are discussed in detail. 展开更多
关键词 entransy theory finite time thermodynamics heat exchange process optimal temperature path generalized heattransfer law generalized thermodynamic optimization
原文传递
Generalized constructal optimization for the secondary cooling process of slab continuous casting based on entransy theory 被引量:14
12
作者 FENG HuiJun CHEN LinGen +2 位作者 XIE ZhiHui DING ZeMin SUN FengRui 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第4期784-795,共12页
Based on constructal theory and entransy theory,a generalized constructal optimization of a solidification heat transfer process of slab continuous casting for a specified total water flow rate in the secondary coolin... Based on constructal theory and entransy theory,a generalized constructal optimization of a solidification heat transfer process of slab continuous casting for a specified total water flow rate in the secondary cooling zone was carried out.A complex function was taken as the optimization objective to perform the casting.The complex function was composed of the functions of the entransy dissipation and surface temperature gradient of the slab.The optimal water distribution at the sections of the secondary cooling zone were obtained.The effects of the total water flow rate in the secondary cooling zone,casting speed,superheat and water distribution on the generalized constructal optimizations of the secondary cooling process were analyzed.The results show that on comparing the optimization results obtained based on the optimal water distributions of the 8 sections in the secondary cooling zone with those based on the initial ones,the complex function and the functions of the entransy dissipation and surface temperature gradient after optimization decreased by 43.25%,5.90%and 80.60%,respectively.The quality and energy storage of the slab had obviously improved in this case.The complex function,composed of the functions of the entransy dissipation and surface temperature gradient of the slab,was a compromise between the internal and surface temperature gradients of the slab.Essentially,it is also the compromise between energy storage and quality of the slab.The"generalized constructal optimization"based on the minimum complex function can provide an optimal alternative scheme from the point of view of improving energy storage and quality for the parameter design and dynamic operation of the solidification heat transfer process of slab continuous casting. 展开更多
关键词 slab continuous casting solidification heat transfer entransy dissipation complex function generalized constructal op- timization generalized thermodynamic optimization
原文传递
Parameter estimation for generalized diffusion processes with reflected boundary 被引量:2
13
作者 ZANG QingPei ZHANG LiXin 《Science China Mathematics》 SCIE CSCD 2016年第6期1163-1174,共12页
Reflected Ornstein-Uhlenbeck process is a process that returns continuously and immediately to the interior of the state space when it attains a certain boundary. It is an extended model of the traditional Ornstein-Uh... Reflected Ornstein-Uhlenbeck process is a process that returns continuously and immediately to the interior of the state space when it attains a certain boundary. It is an extended model of the traditional Ornstein-Uhlenbeck process being extensively used in finance as a one-factor short-term interest rate model. In this paper, under certain constraints, we are concerned with the problem of estimating the unknown parameter in the reflected Ornstein-Uhlenbeck processes with the general drift coefficient. The methodology of estimation is built upon the maximum likelihood approach and the method of stochastic integration. The strong consistency and asymptotic normality of estimator are derived. As a by-product of the use, we also establish Girsanov's theorem of our model in this paper. 展开更多
关键词 reflected Ornstein-Uhlenbeck process maximum likelihood estimation Girsanov's formula Sko-rohod embedding Dambis Dubins-Schwartz Brownian motion
原文传递
Adiabatic and Non-Adiabatic Berry Phases in Generalized J-C Model of Multi-Photon Process 被引量:1
14
作者 刘妮 王月明 梁九卿 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第8期271-274,共4页
We derive the adiabatic and non-adiabatic Berry phases in the generalized Jaynes-Cummings model of multi-photon process. The results show that the adiabatic Berry phase is kept a constant π independent of all the par... We derive the adiabatic and non-adiabatic Berry phases in the generalized Jaynes-Cummings model of multi-photon process. The results show that the adiabatic Berry phase is kept a constant π independent of all the parameters, while the non-adiabatic approximate Berry phase is parameter-dependent, proportional to the average photon number m, and tends to be constant with the increasing detuning. In the ease of exact n-photon resonance and an integer ratio of m/n, the two results coincide with each other, otherwise there appears an additional non-trivial phase factor. 展开更多
关键词 generalized J-C model multi-photon process Berry phase NON-ADIABATIC gauge transformation
原文传递
Generalized Butler-Volmer relation on a curved electrode surface under the action of stress
15
作者 FuQian Yang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第11期44-50,共7页
According to the principle of thermal activation process, the energy state of a material under the action of stress is a function of local stress. A generalized Butler-Volmer relationship for the electrode reaction on... According to the principle of thermal activation process, the energy state of a material under the action of stress is a function of local stress. A generalized Butler-Volmer relationship for the electrode reaction on the surface of a curved electrode is derived,which takes account of the effects of local stress and the radius of mean curvature. From this relationship, the overpotential is found to be proportional to hydrostatic stress and the activation volume under the condition of open circuit. The conditions for the deposition of the material made solely from solute atoms and the formation of surface pits and porous structures are obtained,using the generalized Butler-Volmer relationship. 展开更多
关键词 Butler-Volmer relationship OVERPOTENTIAL stress
原文传递
Generalized fixed-effects and mixed-effects parameters height-diameter models with diffusion processes
16
作者 Petras Rupgys 《International Journal of Biomathematics》 2015年第5期135-157,共23页
Statistical models using stochastic differential equations (SDEs) to describe dynamically evolving natural systems are appearing in the scientific literature with some regularity in recent years. In this study, the ... Statistical models using stochastic differential equations (SDEs) to describe dynamically evolving natural systems are appearing in the scientific literature with some regularity in recent years. In this study, the SDE mixed-effects parameter models based on a Vasicek non-homogeneous diffusion process are formulated. The breast height diameter- dependent drift function additionally depends on deterministic function that describes the dynamic of certain exogenous stand variables (crown height, eh, crown width Cw, mean breast height diameter, do, mean height, ho, age, A, soil fertility index SFI, stocking level, S) versus breast height diameter. The mixed-effects parameters SDE models included a random parameter that affected the models asymptote. The parameter estimators are evaluated by maximum likelihood procedure. The objective of the research was to develop a generalized mixed-effects parameters SDE heightdiameter models and to illustrate issues using dataset of Scots pine trees (Pinus sylvestris L.) in Lithuania with the breast height diameter outside the bark larger than 0cm. The parameters of all used models were estimated using an estimation dataset and were evaluated using a validation dataset. The new developed height diameter models are an improvement over exogenous stand variables, in that it can be calibrated to a new stand with observed height-diameter pairs, thus improving height prediction. 展开更多
关键词 Stochastic differential equation conditional probability density mixed-effectsparameters generalized models.
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部