In this paper, using the stochastic decomposition and renewal theory we provide the direct method for analysis the departure process of single sever M/G/1 queueing system, and further discuss the departure process of ...In this paper, using the stochastic decomposition and renewal theory we provide the direct method for analysis the departure process of single sever M/G/1 queueing system, and further discuss the departure process of GI/G/1 queueing system. The method provided in this paper is new and concise, which make us see dearly the structure of the departure process of a single server queueing system.展开更多
By studying the spectral properties of the underlying operator corresponding to the M/G/1 queueing model with optional second service we obtain that the time-dependent solution of the model strongly converges to its s...By studying the spectral properties of the underlying operator corresponding to the M/G/1 queueing model with optional second service we obtain that the time-dependent solution of the model strongly converges to its steady-state solution. We also show that the time-dependent queueing size at the departure point converges to the corresponding steady-state queueing size at the departure point.展开更多
In this paper, we consider point spectra of the operator corresponding to the M/M/1 queueing model with working vacation and vacation interruption. We prove that the underlying operator has uncountable eigenvalues on ...In this paper, we consider point spectra of the operator corresponding to the M/M/1 queueing model with working vacation and vacation interruption. We prove that the underlying operator has uncountable eigenvalues on the left real line and these results describe the point spectra of the operator. Then, we show that the essential growth bound of the C_0-semigroup generated by the operator is 0 and therefore it is not quasi compact, the essential spectral bound of the C_0-semigroup is equal to 1. Moreover, our results imply it is impossible that the time-dependent solution of the model exponentially converges to its steady-state solution.展开更多
It is well known, in queueing theory, that the system performance is greatly influenced by scheduling policy. No universal optimum scheduling strategy exists in systems where individual customer service demands are no...It is well known, in queueing theory, that the system performance is greatly influenced by scheduling policy. No universal optimum scheduling strategy exists in systems where individual customer service demands are not known a priori. However, if the distribution of job times is known, then the residual time (expected time remaining for a job), based on the service it has already received, can be calculated. Our particular research contribution is in exploring the use of this function to enhance system performance by increasing the probability that a job will meet its deadline. In a detailed discrete event simulation, we have tested many different distributions with a wide range of C2 and shapes, as well as for single and dual processor system. Results of four distributions are reported here. We compare with RR and FCFS, and find that in all distributions studied our algorithm performs best. In the study of the use of two slow servers versus one fast server, we have discovered that they provide comparable performance, and in a few cases the double server system does better.展开更多
The Distributed Queuing (DQ) algorithm is predicted as one of the solutions to the issues currently found in IoT networks over the use of Aloha based algorithms. Since recently, the algorithm has been of interest to m...The Distributed Queuing (DQ) algorithm is predicted as one of the solutions to the issues currently found in IoT networks over the use of Aloha based algorithms. Since recently, the algorithm has been of interest to many IoT researchers as a replacement of those Aloha variants for channel access. However, previous works analyzed and evaluated the DQ algorithm without any consideration of the stability of its queues, assuming it is stable for any given number of nodes in the network. In this paper, we define the DQ stability condition in a single-channel M2M environment considering a traffic model of periodic and urgent frames from each node in the network. Besides, a steady-state evaluation of the algorithm’s performance metrics is also presented. In general, the DQ algorithm, when it is stable, was observed not to efficiently use the contention slots for the collision resolution. In a single-channel environment, the DQ algorithm is found to outperform the Aloha based algorithms only in an idle-to-saturation scenario.展开更多
目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用...目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用第八期T,N,M分期对数据的T,N,M分期进行整理,标准化,筛选,筛选条件为患者第八期T,N,M分期明确,有符合要求的观察结局,如死亡或存活。通过筛查出的患者的不同病理分型的数据,运用SPSS26.0统计软件进行统计描述,采用Kaplan-Meier法。描绘生存曲线并估计患者的生存率,死亡率。生存时间分布的组间比较采用Log-Rank检验,对分析结果中P α = 0.05,以P Objective: Study on the prognostic risk model of cervical cancer patients based on SEER database, analyze the relevant factors affecting the prognosis of cervical cancer, and provide scientific reference for the prognosis recovery and treatment of cervical cancer patients. Methods: The SEER database was used to preliminarily screen the data related to cervical cancer, download the data of different pathological types of cervical cancer patients in line with the study, and select the eighth stage T, N, M to sort out, standardize and screen the T, N and M stages of the data. The screening conditions were that the eighth stage T, N and M stages of patients were clear, and there were satisfactory observed outcomes, such as death or survival. Through the data of different pathological types of patients screened, spss26 0 statistical software for statistical description, using Kaplan Meier method. Draw the survival curve and estimate the survival rate and mortality of patients. The inter group comparison of survival time distribution adopts log rank test to conduct multi factor Cox analysis on the variables with statistical significance of P α = 0.05, P < 0.05. Result: (1) Kaplan Meier univariate analysis: different pathological stages of T stage, N stage and M stage have an impact on the survival of patients, which is statistically significant (P < 0.05), and can affect the survival of patients to varying degrees. (2) Cox multivariate analysis: T stage, N stage and M stage were independent prognostic factors affecting the survival time of patients. Conclusion: Different T, N and M pathological stages of different cervical cancer patients can affect the prognosis of cervical cancer patients to varying degrees. They have a significant impact on the mortality and survival rate of cervical cancer patients, and can provide relevant basis for the development and improvement of the treatment scheme of cervical cancer.展开更多
In the era of big data,traditional statistical inference methods are faced with great challenges.Taking the two-sample distribution test scenario of big data as an example,this paper proposes the BB-KS test based on m...In the era of big data,traditional statistical inference methods are faced with great challenges.Taking the two-sample distribution test scenario of big data as an example,this paper proposes the BB-KS test based on m out of n bootstrap for solving a single-machine memory and computing constraints.It is verified to the feasibility and effectiveness of the proposed test method through theoretical analysis and numerical simulation.The results show that the BB-KS test can improve the calculation efficiency of the test to a certain extent in the single machine scenario.展开更多
文摘In this paper, using the stochastic decomposition and renewal theory we provide the direct method for analysis the departure process of single sever M/G/1 queueing system, and further discuss the departure process of GI/G/1 queueing system. The method provided in this paper is new and concise, which make us see dearly the structure of the departure process of a single server queueing system.
基金supported by the National Natural Science Foundation of China(11371303)Natural Science Foundation of Xinjiang(2012211A023)Science Foundation of Xinjiang University(XY110101)
文摘By studying the spectral properties of the underlying operator corresponding to the M/G/1 queueing model with optional second service we obtain that the time-dependent solution of the model strongly converges to its steady-state solution. We also show that the time-dependent queueing size at the departure point converges to the corresponding steady-state queueing size at the departure point.
基金Supported by the National Natural Science Foundation of China(Grant No.11801485)
文摘In this paper, we consider point spectra of the operator corresponding to the M/M/1 queueing model with working vacation and vacation interruption. We prove that the underlying operator has uncountable eigenvalues on the left real line and these results describe the point spectra of the operator. Then, we show that the essential growth bound of the C_0-semigroup generated by the operator is 0 and therefore it is not quasi compact, the essential spectral bound of the C_0-semigroup is equal to 1. Moreover, our results imply it is impossible that the time-dependent solution of the model exponentially converges to its steady-state solution.
文摘It is well known, in queueing theory, that the system performance is greatly influenced by scheduling policy. No universal optimum scheduling strategy exists in systems where individual customer service demands are not known a priori. However, if the distribution of job times is known, then the residual time (expected time remaining for a job), based on the service it has already received, can be calculated. Our particular research contribution is in exploring the use of this function to enhance system performance by increasing the probability that a job will meet its deadline. In a detailed discrete event simulation, we have tested many different distributions with a wide range of C2 and shapes, as well as for single and dual processor system. Results of four distributions are reported here. We compare with RR and FCFS, and find that in all distributions studied our algorithm performs best. In the study of the use of two slow servers versus one fast server, we have discovered that they provide comparable performance, and in a few cases the double server system does better.
文摘The Distributed Queuing (DQ) algorithm is predicted as one of the solutions to the issues currently found in IoT networks over the use of Aloha based algorithms. Since recently, the algorithm has been of interest to many IoT researchers as a replacement of those Aloha variants for channel access. However, previous works analyzed and evaluated the DQ algorithm without any consideration of the stability of its queues, assuming it is stable for any given number of nodes in the network. In this paper, we define the DQ stability condition in a single-channel M2M environment considering a traffic model of periodic and urgent frames from each node in the network. Besides, a steady-state evaluation of the algorithm’s performance metrics is also presented. In general, the DQ algorithm, when it is stable, was observed not to efficiently use the contention slots for the collision resolution. In a single-channel environment, the DQ algorithm is found to outperform the Aloha based algorithms only in an idle-to-saturation scenario.
文摘目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用第八期T,N,M分期对数据的T,N,M分期进行整理,标准化,筛选,筛选条件为患者第八期T,N,M分期明确,有符合要求的观察结局,如死亡或存活。通过筛查出的患者的不同病理分型的数据,运用SPSS26.0统计软件进行统计描述,采用Kaplan-Meier法。描绘生存曲线并估计患者的生存率,死亡率。生存时间分布的组间比较采用Log-Rank检验,对分析结果中P α = 0.05,以P Objective: Study on the prognostic risk model of cervical cancer patients based on SEER database, analyze the relevant factors affecting the prognosis of cervical cancer, and provide scientific reference for the prognosis recovery and treatment of cervical cancer patients. Methods: The SEER database was used to preliminarily screen the data related to cervical cancer, download the data of different pathological types of cervical cancer patients in line with the study, and select the eighth stage T, N, M to sort out, standardize and screen the T, N and M stages of the data. The screening conditions were that the eighth stage T, N and M stages of patients were clear, and there were satisfactory observed outcomes, such as death or survival. Through the data of different pathological types of patients screened, spss26 0 statistical software for statistical description, using Kaplan Meier method. Draw the survival curve and estimate the survival rate and mortality of patients. The inter group comparison of survival time distribution adopts log rank test to conduct multi factor Cox analysis on the variables with statistical significance of P α = 0.05, P < 0.05. Result: (1) Kaplan Meier univariate analysis: different pathological stages of T stage, N stage and M stage have an impact on the survival of patients, which is statistically significant (P < 0.05), and can affect the survival of patients to varying degrees. (2) Cox multivariate analysis: T stage, N stage and M stage were independent prognostic factors affecting the survival time of patients. Conclusion: Different T, N and M pathological stages of different cervical cancer patients can affect the prognosis of cervical cancer patients to varying degrees. They have a significant impact on the mortality and survival rate of cervical cancer patients, and can provide relevant basis for the development and improvement of the treatment scheme of cervical cancer.
文摘In the era of big data,traditional statistical inference methods are faced with great challenges.Taking the two-sample distribution test scenario of big data as an example,this paper proposes the BB-KS test based on m out of n bootstrap for solving a single-machine memory and computing constraints.It is verified to the feasibility and effectiveness of the proposed test method through theoretical analysis and numerical simulation.The results show that the BB-KS test can improve the calculation efficiency of the test to a certain extent in the single machine scenario.
