期刊文献+
共找到153篇文章
< 1 2 8 >
每页显示 20 50 100
Equivalence of Subclasses of Two-Way Non-Deterministic Watson Crick Automata
1
作者 Kumar Sankar Ray Kingshuk Chatterjee Debayan Ganguly 《Applied Mathematics》 2013年第10期26-34,共9页
Watson Crick automata are finite automata working on double strands. Extensive research work has already been done on non deterministic Watson Crick automata and on deterministic Watson Crick automata. Parallel Commun... Watson Crick automata are finite automata working on double strands. Extensive research work has already been done on non deterministic Watson Crick automata and on deterministic Watson Crick automata. Parallel Communicating Watson Crick automata systems have been introduced by E. Czeziler et al. In this paper we discuss about a variant of Watson Crick automata known as the two-way Watson Crick automata which are more powerful than non-deterministic Watson Crick automata. We also establish the equivalence of different subclasses of two-way Watson crick automata. We further show that recursively enumerable (RE) languages can be realized by an image of generalized sequential machine (gsm) mapping of two-way Watson-Crick automata. 展开更多
关键词 non-deterministic WATSON CRICK AUTOMATA Two-Way non-deterministic WATSON CRICK AUTOMATA RE LANGUAGES
下载PDF
Prediction of Ground Water Level in Arid Environment Using a Non-Deterministic Model
2
作者 Mohammad Mirzavand Seyed Javad Sadatinejad +2 位作者 Hoda Ghasemieh Rasool Imani Mehdi Soleymani Motlagh 《Journal of Water Resource and Protection》 2014年第7期669-676,共8页
Modeling and forecasting of the groundwater water table are a major component of effective planning and management of water resources. One way to predict the groundwater level is analysis using a non-deterministic mod... Modeling and forecasting of the groundwater water table are a major component of effective planning and management of water resources. One way to predict the groundwater level is analysis using a non-deterministic model. This study assessed the performance of such models in predicting the groundwater level at Kashan aquifer. Data from 36 piezometer wells in Kashan aquifer for 1999 to 2010 were used. The desired statistical interval was divided into two parts and statistics for 1990 to 2004 were used for modeling and statistics from 2005 to 2010 were used for valediction of the model. The Akaike criterion and correlation coefficients were used to determine the accuracy of the prediction models. The results indicated that the AR(2) model more accurately predicted ground water level in the plains;using this model, the groundwater water table was predicted for up to 60 mo. 展开更多
关键词 non-deterministic MODELS Akaike CRITERION GROUND Water LEVEL Kashan AQUIFER
下载PDF
Exploiting Virtual Elasticity of Production Systems to Respect OTD—Part 3: Basic Considerations for Modelling CPPS Characterized by Non-Ergodic Order Entry and Non-Deterministic Product-Mix for Fully Flexible Addressable Workstations
3
作者 Bruno G. Rüttimann Martin T. Stöckli 《American Journal of Operations Research》 2022年第2期19-63,共45页
The recently experienced hype concerning the so-called “4<sup>th</sup> Industrial Revolution” of production systems has prompted several papers of various subtopics regarding Cyber-Phdysical Production S... The recently experienced hype concerning the so-called “4<sup>th</sup> Industrial Revolution” of production systems has prompted several papers of various subtopics regarding Cyber-Phdysical Production Systems (CPPS). However, important aspects such as the modelling of CPPS to understand the theory regarding the performance of highly non-ergodic and non-deterministic flexible manufacturing systems in terms of Exit Rate (ER), Manufacturing Lead Time (MLT), and On-Time Delivery (OTD) have not yet been examined systematically and even less modeled analytically. To develop the topic, in this paper, the prerequisites for modelling such systems are defined in order to be able to derive an explicit and dedicated production mathematics-based understanding of CPPS and its dynamics: switching from explorative simulation to rational modelling of the manufacturing “physics” led to an own and specific manufacturing theory. The findings have led to enouncing, among others, the Theorem of Non-Ergodicity as well as the Batch Cycle Time Deviation Function giving important insights to model digital twin-based CPPS for complying with the mandatory OTD. 展开更多
关键词 On-Time-Delivery Production System Industry 4.0 CPPS IoT Stochastic Arrival Rate non-Ergodic Process Virtual Elasticity Production Capacity Nominal Mean Exit Rate Theorem of non-Ergodicity non-deterministic Product-Mix TFL AGV Scheduling Algorithm Digital Twin
下载PDF
MODS: A Novel Metaheuristic of Deterministic Swapping for the Multi-Objective Optimization of Combinatorials Problems
4
作者 Elias David Nifio Ruiz Carlos Julio Ardila Hemandez +2 位作者 Daladier Jabba Molinares Agustin Barrios Sarmiento Yezid Donoso Meisel 《Computer Technology and Application》 2011年第4期280-292,共13页
This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Auto... This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Automata (MDFA) is defined. MDFA allows the representation of the feasible solutions space of combinatorial problems. Second, it is defined and implemented a metaheuritic based on MDFA theory. It is named Metaheuristic of Deterministic Swapping (MODS). MODS is a local search strategy that works using a MDFA. Due to this, MODS never take into account unfeasible solutions. Hence, it is not necessary to verify the problem constraints for a new solution found. Lastly, MODS is tested using well know instances of the Bi-Objective Traveling Salesman Problem (TSP) from TSPLIB. Its results were compared with eight Ant Colony inspired algorithms and two Genetic algorithms taken from the specialized literature. The comparison was made using metrics such as Spacing, Generational Distance, Inverse Generational Distance and No-Dominated Generation Vectors. In every case, the MODS results on the metrics were always better and in some of those cases, the superiority was 100%. 展开更多
关键词 METAHEURISTIC deterministic finite automata combinatorial problem multi - objective optimization metrics.
下载PDF
采用Karhunen-Loève分解计算堤坝沉降区间场
5
作者 周婷 介玉新 张延亿 《水力发电学报》 CSCD 北大核心 2024年第5期103-114,共12页
大坝的建造以及运行过程中受多种内外部多因素耦合作用,其沉降分析是复杂、非线性问题,采用非概率区间方法构造大坝沉降区间有利于定量描述多源不确定信息,使计算更加吻合实际情况。本文将基于Karhunen-Loève分解的区间场有限元方... 大坝的建造以及运行过程中受多种内外部多因素耦合作用,其沉降分析是复杂、非线性问题,采用非概率区间方法构造大坝沉降区间有利于定量描述多源不确定信息,使计算更加吻合实际情况。本文将基于Karhunen-Loève分解的区间场有限元方法由线弹性模型扩展至邓肯-张模型中,通过引入平方指数形式的空间依赖函数描述切线模量的空间变异性。采用以Legendre多项式为基函数的Galerkin方法计算模量变化区域的特征值与特征函数。在区间有限元的框架下,编写非线性区间本构模型Abaqus用户子程序UMAT,结合Python脚本计算大坝沉降针对于模量参数变化的响应区间,并与传统顶点集区间方法进行对比。工程实例分析表明,所提方法可以有效计算大坝沉降区间,所得到的沉降区间能涵盖顶点集区间,且有限元计算次数由指数级减少为多项式级。本文方法可以进一步扩展至大坝长期变形区间计算问题。 展开更多
关键词 大坝沉降 非确定性分析 区间场有限元 Karhunen-Loève分解 GALERKIN方法
下载PDF
肥胖儿童non-HDL-C、remnant cholesterol与亚临床动脉粥样硬化的关系 被引量:4
6
作者 焦朝艳 刘戈力 +4 位作者 鲍鹏丽 魏莹 杨箐岩 郑荣秀 赵菁 《天津医科大学学报》 2014年第1期25-28,共4页
目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体... 目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体质量儿童30例为III组(对照组)。比较3组儿童血脂指标,对肥胖组各项血脂指标与血浆致动脉粥样硬化指数(AIP)进行相关性分析,肥胖患儿体质指数、血脂指标与颈动脉内径、内膜-中层厚度(c-IMT)、血流参数进行相关性分析。结果:I组、II组的TG、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、non-HDL-C、remnant cholesterol、AIP均较对照组升高,高密度脂蛋白胆固醇(HDL-C)较对照组降低,且I组的remnant cholesterol、AIP均较II组升高。肥胖组儿童AIP与TG、non-HDL-C、remnant cholesterol呈正相关,与HDL-C呈负相关。37例行颈动脉超声检查的肥胖儿童的c-IMT较正常儿童的增厚。结论:non-HDL-C、remnant cholesterol在肥胖儿童亚临床AS中有重要作用,在肥胖儿童血脂异常的治疗中应关注non-HDL-C、remnant cholesterol的变化。 展开更多
关键词 儿童肥胖 亚临床动脉粥样硬化 non—HDL—C REMNANT CHOLESTEROL 血浆致动脉粥样硬化指数 颈动脉内膜-中层厚度
下载PDF
Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced non-small cell lung cancer: a meta-analysis 被引量:13
7
作者 Qiang Zhang Yi-Huan Fan +2 位作者 Teng Zhang Xiao-Lan Qin Ji-Fang Song 《TMR Integrative Medicine》 2017年第2期68-78,共11页
Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a syst... Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a systematicsearch in the electronic databases such as Cochrane Library, Pubmed, Embase, Chinese Journal Full-text Database,Chinese Biomedical Literature Database, Chinese Science and Technology Periodical Full-text Database andWanfang Database up to 30 January 2017. Randomized controlled trials (RCT) of Shenqi Fuzheng Injectioncombined with GP chemotherapy in the treatment of advanced NSCLC were searched, and all the RCTs wereconducted on methodological quality assessment. Data extraction and data analysis were according to standards ofCochrane systematic review. Results: Eight trials were included including a total of 701 patients. Meta-analysisresults: Shenqi Fuzheng injection combined with GP chemotherapy could significantly improve the functionalstatus of patients with NSCLC (OR = 3.44, 95% CI [2.26, 5.25], P 〈 0.0001) and clinical treatment efficacy (OR =(OR = 0.31, 95%CI [0.20, 0.47], P 〈 0.0001. The rate of leukopenia (OR = .31, 95%CI [0.20,0.47], P 〈 0.0001),thrombocytopenia (OR = 0.58, 95%CI [0.37, 0.91], P = 0.020), hemoglobin decline ((OR = 0.31, 95%CI [0.16,0.59], P = 0.0004) and incidence of gastrointestinal reactions (OR = 0.58,P 〈 0.05) could be reduced. Conclusion:Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced NSCLC obtainedsignificantly clinical efficacy. The quality of the literature incorporated is low, the conclusion requires high-qualityresearch to further prove. 展开更多
关键词 Shenqi Fuzheng GP chemotherapy Advanced non - small cell lung cancer Meta analysis
下载PDF
A Non-Preemptive Priority Queueing System with a Single Server Serving Two Queues M/G/1 and M/D/1 with Optional Server Vacations Based on Exhaustive Service of the Priority Units
8
作者 Kailash C. Madan 《Applied Mathematics》 2011年第6期791-799,共9页
We study a vacation queueing system with a single server simultaneously dealing with an M/G/1 and an M/D/1 queue. Two classes of units, priority and non-priority, arrive at the system in two independent Poisson stream... We study a vacation queueing system with a single server simultaneously dealing with an M/G/1 and an M/D/1 queue. Two classes of units, priority and non-priority, arrive at the system in two independent Poisson streams. Under a non-preemptive priority rule, the server provides a general service to the priority units and a deterministic service to the non-priority units. We further assume that the server may take a vacation of random length just after serving the last priority unit present in the system. We obtain steady state queue size distribution at a random epoch. Corresponding results for some special cases, including the known results of the M/G/1 and the M/D/1 queues, have been derived. 展开更多
关键词 non PREEMPTIVE PRIORITY QUEUEING SYSTEM Modified Server Vacations Combination of General SERVICE and deterministic SERVICE Steady State Queue Size Distribution
下载PDF
Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field
9
作者 Hong-tao Zheng Zhi-yong Tan +2 位作者 Hai-ou Sun Chun-liang Zhou Zhi-ming Li 《Journal of Marine Science and Application》 2002年第1期26-34,共9页
Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved... Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec- 展开更多
关键词 plasma GENERATOR CHEMISTRY non - EQUILIBRIUM IGNITION technique numerical calculation
下载PDF
Turbulent Flow Action of Pulp in Wet - Laid Non - Woven Processes
10
作者 程隆棣 黄秀宝 于修业 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期57-59,共3页
The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and prac... The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and practice.The suitable use of the imported velocity of pulp is very important in producing wet-laid products of good quality. 展开更多
关键词 WET - laid non - woven fiber PULP FLOW TURBULENT FLOW layer FLUID occluded FLUID .
下载PDF
CYFRA 21-1 as an early predictor of first line chemotherapy response in advanced non small cell lung cancer
11
作者 Kashif Iqbal 《The Chinese-German Journal of Clinical Oncology》 CAS 2007年第3期250-253,共4页
Objective: In an era of ever evolving, promising new therapies for advanced non small cell lung cancer (NSCLC), early predictors of response to therapy, are needed. We evaluated early variations in CYFRA 21-1 serum... Objective: In an era of ever evolving, promising new therapies for advanced non small cell lung cancer (NSCLC), early predictors of response to therapy, are needed. We evaluated early variations in CYFRA 21-1 serum levels of patients with advanced NSCLC receiving first line chemotherapy and correlated the results with objective tumor response. Methods: 29 consecutive, previously untreated, patients of advanced non small cell lung cancer, with measurable disease on CT scan were evaluated. All patients were treated with conventional systemic chemotherapy, although the choice of chemotherapy was left to the discretion of the treating physicians. Serum samples were obtained immediately before the start of 1st and 2nd cycles of chemotherapy. CYFRA 21-1 was measured with an electrochemiluminescense immunoassay on an automatic analyzer (Elecsys 2000; Roche Diagnostics). Response was evaluated using Response evaluation criteria in solid tumors (RECIST) criteria. Results: 10 patients had partial response, 9 patients had stable disease and 9 had progressive disease. None of the patients had complete response. 21/29 (72%) patients had an elevated baseline value of CYFRA 21-1.62% patients (18/29) had a decrease in CYFRA 21-1 after 1 cycle of chemotherapy. The average reduction in the 2nd reading was irrespective of whether baseline value was normal or not. The average reduction was statistically significant (P = 0.002; 95% CI, from 0.8369 to 3.49464; t test). 8 out of 10 (80%) patients with partial response had a reduction in their 2nd reading of. CYFRA (P = 0.019; 95% CI, from 0.81965 to 7.20035; t test) which was significant. We also observed that 6/9 (66%) patients whose disease remains stable also had a decrease in their subsequent reading (P = 0.0106; 95% CI, from -0.44942 to 3.82720; t test), though it was not significant statistically. Although 5 out of 9 (55%) patients, who had an increase in their CYFRA 21-1 level, had progressive disease, but it was not statistically significant (P = 0.537; 95% CI, from -1.20021 to 2.13354; ttest). 14 out of 19 (73%) who either had partial response or had stable disease, had a reduction in their 2nd value of CYFRA 21-1 and was significant statistically (P = 0.004; 95% CI, from 0.74792 to 3.50208; t test). We also observed that except for 1 patient, all patients who had a decrease of 42% or more in their subsequent CYFRA 21-1 level, were those who had either responded to chemotherapy or had stable disease (P = 0.001), which was statistically significant. Conclusion: We can conclude that monitoring of serum marker CYFRA 21-1, early dudng first-line chemotherapy may be a useful prognostic tool for evaluation of early tumor response in patients with advanced NSCLC. 展开更多
关键词 CYFRA 21-1 non small cell lung cancer CHEMOTHERAPY RESPONSE
下载PDF
MiR-16-5p plays an inhibitory role in human non-small cell lung cancer through Fermitin family member 2
12
作者 JUNQI GUO YUN YANG +6 位作者 WEI ZHAO ZHONGHAI YAN XIA YANG YUNFEI YAN RUIMIN HAO JINXIA HU FEI JIAO 《BIOCELL》 SCIE 2021年第3期627-638,共12页
Increasing evidence indicates that aberrant expressions of some microRNAs are associated with cancer progression.However,the roles and biological mechanisms of miRNA-16-5p in human non-small cell lung cancer(NSCLC)are... Increasing evidence indicates that aberrant expressions of some microRNAs are associated with cancer progression.However,the roles and biological mechanisms of miRNA-16-5p in human non-small cell lung cancer(NSCLC)are not to be well studied.Here,we validated that the expression of miR-16-5p was decreased significantly in NSCLC samples and cell lines.The correlation between the clinicopathological features of NSCLC and the miR-16-5p expression showed that the expression of miR-16-5p in non-small cell lung cancer was linked with the advanced TNM stage,positive lymph node metastasis,with short overall survival(OS).Also,a negative correlation between miR-16-5p and Fermitin family member 2(FERMT2)was observed,implying there may be a potential link about their regulation.The hypothesis was further confirmed by in-silico analysis and dual-luciferase reporter assay.Moreover,we demonstrated that the transfections of miR-16-5p mimics could alter some biological characteristics of NSCLC cells remarkably accomplished by the expression variance of FERMT2 in vitro and in vivo assays.Summarily,this study demonstrated that miR-16-5p,as a tumor suppression factor in NSCLC by targeting FERMT2,could serve as one promising biomarker in the prediction for NSCLC patients. 展开更多
关键词 miR-16-5p non–small-cell lung cancer(NSCLC) Fermitin family member 2(FERMT2) APOPTOSIS INVASION Overall survival(OS)
下载PDF
Testing for Deterministic Components in Vector Seasonal Time Series
13
作者 José Luis Gallego Carlos Díaz 《Open Journal of Statistics》 2011年第3期145-150,共6页
Certain locally optimal tests for deterministic components in vector time series have associated sampling distributions determined by a linear combination of Beta variates. Such distributions are nonstandard and must ... Certain locally optimal tests for deterministic components in vector time series have associated sampling distributions determined by a linear combination of Beta variates. Such distributions are nonstandard and must be tabulated by Monte Carlo simulation. In this paper, we provide closed form expressions for the mean and variance of several multivariate test statistics, moments that can be used to approximate unknown distributions. In particular, we find that the two-moment Inverse Gaussian approximation provides a simple and fast method to compute accurate quantiles and p-values in small and asymptotic samples. To illustrate the scope of this approximation we review some standard tests for deterministic trends and/or seasonal patterns in VARIMA and structural time series models. 展开更多
关键词 VECTOR Time Series deterministic Components PARAMETRIC Stability non-Invertibility Unit ROOTS
下载PDF
CR-NOMA中基于深度确定策略梯度的能效优化策略
14
作者 张云 《电信科学》 北大核心 2024年第5期112-120,共9页
利用认知无线电非正交多址接入(cognitive radio non-orthogonal multiple access,CR-NOMA)技术可缓解频谱资源短缺问题,提升传感设备的吞吐量。传感设备的能效问题一直制约着传感设备的应用。为此,针对CR-NOMA中的传感设备,提出基于深... 利用认知无线电非正交多址接入(cognitive radio non-orthogonal multiple access,CR-NOMA)技术可缓解频谱资源短缺问题,提升传感设备的吞吐量。传感设备的能效问题一直制约着传感设备的应用。为此,针对CR-NOMA中的传感设备,提出基于深度确定策略梯度的能效优化(deep deterministic policy gradientbased energy efficiency optimization,DPEE)算法。DPEE算法通过联合优化传感设备的传输功率和时隙分裂系数,提升传感设备的能效。将能效优化问题建模成马尔可夫决策过程,再利用深度确定策略梯度法求解。最后,通过仿真分析了电路功耗、时隙时长和主设备数对传感能效的影响。仿真结果表明,能效随传感设备电路功耗的增加而下降。此外,相比于基准算法,提出的DPEE算法提升了能效。 展开更多
关键词 传感设备 能量采集 认知无线电非正交多址接入 能效 深度确定策略梯度
下载PDF
基于深度强化学习的IRS辅助NOMA-MEC通信资源分配优化
15
作者 方娟 刘珍珍 +1 位作者 陈思琪 李硕朋 《北京工业大学学报》 CAS CSCD 北大核心 2024年第8期930-938,共9页
为了解决无法与边缘服务器建立直连通信链路的盲区边缘用户卸载任务的问题,设计了一个基于深度强化学习(deep reinforcement learning, DRL)的智能反射面(intelligent reflecting surface, IRS)辅助非正交多址(non-orthogonal multiple ... 为了解决无法与边缘服务器建立直连通信链路的盲区边缘用户卸载任务的问题,设计了一个基于深度强化学习(deep reinforcement learning, DRL)的智能反射面(intelligent reflecting surface, IRS)辅助非正交多址(non-orthogonal multiple access, NOMA)通信的资源分配优化算法,以获得由系统和速率和能源效率(energy efficiency, EE)加权的最大系统收益,从而实现绿色高效通信。通过深度确定性策略梯度(deep deterministic policy gradient, DDPG)算法联合优化传输功率分配和IRS的反射相移矩阵。仿真结果表明,使用DDPG算法处理移动边缘计算(mobile edge computing, MEC)的通信资源分配优于其他几种对比实验算法。 展开更多
关键词 非正交多址(non-orthogonal multiple access NOMA) 智能反射面(intelligent reflecting surface IRS) 深度确定性策略梯度(deep deterministic policy gradient DDPG)算法 移动边缘计算(mobile edge computing MEC) 能源效率(energy efficiency EE) 系统收益
下载PDF
基于UPPAAL-TRON的高速铁路列控系统非确定性时延一致性测试研究 被引量:6
16
作者 吕继东 朱晓琳 +2 位作者 王海峰 李开成 唐涛 《铁道学报》 EI CAS CSCD 北大核心 2016年第1期54-64,共11页
高速铁路列车运行控制系统是一个典型的实时系统,如何保证列控系统在时延约束条件下功能实现的正确性至关重要。传统的离线测试方法已广泛用于列控系统功能一致性测试中,然而,随着系统复杂度的提高,物理环境中时延的非确定性制约传统离... 高速铁路列车运行控制系统是一个典型的实时系统,如何保证列控系统在时延约束条件下功能实现的正确性至关重要。传统的离线测试方法已广泛用于列控系统功能一致性测试中,然而,随着系统复杂度的提高,物理环境中时延的非确定性制约传统离线测试方法的应用。本文引入"在线测试"的概念,利用时间自动机理论对典型场景车载设备的RBC切换过程建模,并定义可观测消息通道将该模型划分为环境和设备两部分,从而借助工具UPPAAL-TRON"边生成边执行"测试用例,找出了在非确定性时延下,仿真RBC测试模型与测试需求中不一致的地方。并通过改进测试模型中RBC处理占用参数的设置,实现对RBC切换过程中跨界传递联锁消息时延非确定性的一致性测试。 展开更多
关键词 列控系统 非确定性时延 一致性测试 UPPAAL-TRON RBC切换
下载PDF
原油采购-远洋运输方案模糊聚类图优化法 被引量:6
17
作者 肖文涛 徐宁 +3 位作者 刘志玲 周晓玲 王震 李启 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第3期176-182,共7页
总结中国原油采购-远洋运输业务流程,分析原油采购-远洋运输方案优化问题的特殊属性。原油采购-远洋运输方案优化是包含多种高维度变量的动态-模糊组合优化的大规模NP(non-deterministic polynomial)难问题,需要多个区域业务人员根据市... 总结中国原油采购-远洋运输业务流程,分析原油采购-远洋运输方案优化问题的特殊属性。原油采购-远洋运输方案优化是包含多种高维度变量的动态-模糊组合优化的大规模NP(non-deterministic polynomial)难问题,需要多个区域业务人员根据市场和需求的动态变化协作完成,超出现有方法的解决范畴。提出模糊聚类图优化法,通过实时挖掘和利用启发性优化信息以及全局视野拼接由启发式算法所搜索到的局部静态优化方案,实现大规模原油采购-远洋运输方案的全局优化。应用结果表明,模糊聚类图优化法弥补了传统建模求解的方法的不足,充分结合了人的灵活决策优势与计算机暴力计算特点,可辅助业务人员适应原油采购-远洋运输方案优化的动态-模糊特性,通过合理调整运输任务(即调整优化模型的目标函数和限制条件)实现原油采购-远洋运输方案优化,具有较强的决策支持作用。 展开更多
关键词 原油远洋运输优化 NP难问题 差分进化算法 聚类图解法
下载PDF
中子-中子碰撞非线性输运的确定论模拟 被引量:1
18
作者 黄凯 傅学东 +2 位作者 应阳君 李金鸿 竹生东 《强激光与粒子束》 EI CAS CSCD 北大核心 2018年第11期146-153,共8页
从几个方面着手提高确定论方法的计算精度:首先,中子输运计算的相空间离散采用间断有限元处理方法,并使用较大的角度离散数和散射阶数;其次,使用蒙特卡罗直接统计方法得到高精度多群截面;最后,引入收敛于真解的中子-中子碰撞源迭代。数... 从几个方面着手提高确定论方法的计算精度:首先,中子输运计算的相空间离散采用间断有限元处理方法,并使用较大的角度离散数和散射阶数;其次,使用蒙特卡罗直接统计方法得到高精度多群截面;最后,引入收敛于真解的中子-中子碰撞源迭代。数值算例验证表明,经过改进的确定论方法具有良好的稳定性和精度,能以可靠的精度求解考虑中子-中子碰撞过程的非线性问题。 展开更多
关键词 中子-中子碰撞 确定论 非线性输运 碰撞源迭代 间断有限元
下载PDF
FAREY SEQUENCE OF NONLINEAR DIFFERENTIAL DYNAMIC SYSTEM IN TWO DIMENSIONS 被引量:1
19
作者 H. Q. Jin and S. N. Xu Shenyang Institute of Technology , Shenyang 110015 , China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1234-1236,共3页
In this paper , through the discrim ination of Farey sequence in the forced Brusselator withweak coupling , it is proved that there is a topological translation fro m a nonlinear differen tial system ( limit cycle)... In this paper , through the discrim ination of Farey sequence in the forced Brusselator withweak coupling , it is proved that there is a topological translation fro m a nonlinear differen tial system ( limit cycle) to the circle m ap . 展开更多
关键词 non - linearity Farey sequence phase lock CHAOS
下载PDF
Ways to Overcome Anxiety in the English Listening Class in College (SUN JING-YU KE SU-FEN)
20
作者 孙晶玉 柯素芬 《呼伦贝尔学院学报》 1999年第1期74-77,87,共5页
In my ten-yeat experience of tenching English as major in college , I feel that students experience more difficulties in listening lessons than in other lessons. What, then, prevents students from achieving success in... In my ten-yeat experience of tenching English as major in college , I feel that students experience more difficulties in listening lessons than in other lessons. What, then, prevents students from achieving success in the listening class? I suggest that anxiety is one of the major factors, which interferes with students listening comprehension. And I would agree with writers such as Gardner and Horwitz et al. (1991)that anxiety may impede learner’s ability to perform successfully in all aspects of learning a foreign language. I feet it is particularly significant for listening. 展开更多
关键词 LISTENING anxiety creation of non - ANXIETY environment skills and process focus COUNSELLING corner exposure to authentic English
下载PDF
上一页 1 2 8 下一页 到第
使用帮助 返回顶部