Upper Bounds on Performance Measures of Heterogeneous Queues

In many real-life queueing systems, the servers are often heterogeneous, namely they work at different rates. This paper provides a simple method to compute tight upper bounds on two important performance measures of single-class heterogeneous multi-server Markovian queueing systems, namely the average number in queue and the average waiting time in queue. This method is based on an expansion of the state space that is followed by an approximate reduction of the state space, only considering the most probable states. In most cases tested, we were able to approximate the actual behavior of the system with smaller errors than those obtained from traditional homogeneous multiserver Markovian queues, as shown by GPSS simulations. In addition, we have correlated the quality of the approximation with the degree of heterogeneity of the system, which was evaluated using its Gini index. Finally, we have shown that the bounds are robust and still useful, even considering quite different allocation strategies. A large number of simulation results show the accuracy of the proposed method that is better than that of classical homogeneous multiserver Markovian formulae in many situations.

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Concentration of Measure for Products of Markov Kernels and Graph Products via Functional Inequalities

Combinatorics Probability Computing ◽

10.1017/s0963548300004594 ◽

2001 ◽

Vol 10 (1) ◽

pp. 1-28 ◽

Cited By ~ 2

Author(s):

C. HOUDRÉ ◽

P. TETALI

Keyword(s):

State Space ◽

Spectral Gap ◽

Upper Bounds ◽

The State ◽

Concentration Of Measure ◽

Concentration Inequalities ◽

Functional Inequalities ◽

Graph Products ◽

Markov Kernels

We present versions of concentration inequalities for products of Markov kernels and graph products. We also present discussions of a variety of consequences such as sharp upper bounds, in terms of the diameter of the state space, on the spectral gap.

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Image Thresholding Segmentation on Quantum State Space

Entropy ◽

10.3390/e20100728 ◽

2018 ◽

Vol 20 (10) ◽

pp. 728 ◽

Cited By ~ 2

Author(s):

Xiangluo Wang ◽

Chunlei Yang ◽

Guo-Sen Xie ◽

Zhonghua Liu

Keyword(s):

State Space ◽

Quantum State ◽

Structural Characteristics ◽

The State ◽

Entropy Maximization ◽

Image Thresholding ◽

Optimal Thresholds ◽

Segmented Images ◽

Computation Speed

Aiming to implement image segmentation precisely and efficiently, we exploit new ways to encode images and achieve the optimal thresholding on quantum state space. Firstly, the state vector and density matrix are adopted for the representation of pixel intensities and their probability distribution, respectively. Then, the method based on global quantum entropy maximization (GQEM) is proposed, which has an equivalent object function to Otsu’s, but gives a more explicit physical interpretation of image thresholding in the language of quantum mechanics. To reduce the time consumption for searching for optimal thresholds, the method of quantum lossy-encoding-based entropy maximization (QLEEM) is presented, in which the eigenvalues of density matrices can give direct clues for thresholding, and then, the process of optimal searching can be avoided. Meanwhile, the QLEEM algorithm achieves two additional effects: (1) the upper bound of the thresholding level can be implicitly determined according to the eigenvalues; and (2) the proposed approaches ensure that the local information in images is retained as much as possible, and simultaneously, the inter-class separability is maximized in the segmented images. Both of them contribute to the structural characteristics of images, which the human visual system is highly adapted to extract. Experimental results show that the proposed methods are able to achieve a competitive quality of thresholding and the fastest computation speed compared with the state-of-the-art methods.

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Application of Digital Filters to Check Quality of the Automatically Scaled Ionograms

Journal of Electrical Engineering ◽

10.2478/jee-2015-0026 ◽

2015 ◽

Vol 66 (3) ◽

pp. 164-168 ◽

Cited By ~ 5

Author(s):

Luboš Rejfek ◽

Zbyšek Mošna ◽

Daniel Kouba ◽

Josef Boška ◽

Dalia Burešová

Keyword(s):

Impulse Response ◽

Digital Filters ◽

Finite Impulse Response ◽

The State ◽

Simple Method ◽

Automatic Scaling ◽

Finite Impulse Response Filters ◽

Basic Characteristics ◽

Impulse Response Filters

Abstract The ionospheric observatory Pruhonice serves to monitor the state of ionosphere using ground-based vertical sounding instrument - the Digisonde DPS-4D. Measured ionograms are automatically evaluated (scaled) and basic characteristics are derived. The ionograms and the scaled parameters are sent to the international databases. Especially during disturbed conditions the automatic scaling could give unreliable results. This paper presents simple method how to detect accidental errors in automatic scaling based on the parameters derived from ionograms and on an application of the finite impulse response filters.

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PENYIMPANGAN FUNGSI DAN NILAI-NILAI PANCASILA DALAM PENEGAKAN HUKUM SEBAGAI PEDOMAN HIDUP DALAM BERMASYARAKA

Hukum Dan Dinamika Masyarakat ◽

10.36356/hdm.v16i1.849 ◽

2018 ◽

Vol 16 (1) ◽

Author(s):

Ervina Dwi Indriastuti

Keyword(s):

Real Life ◽

The State ◽

Hard Work ◽

Legal Norm ◽

Founding Fathers ◽

The Republic ◽

Gt Element ◽

The Mind ◽

Laws And Regulations

Pancasila has become the agreement of the Indonesian people as the basis of the Unitary State of the Republic of Indonesia, but in its implementation efforts experience various obstacles both internal and external. Pancasila as a view of the nation's life needs to be implemented in real life, this has been exemplified by the founding fathers of the nation through hard work and struggle to produce Indonesian independence. Concern for the legal conditions that are in favor so far from the element of justice makes the mind interested in discussing whether the values taught by Pancasila are still heeded or ignored. Pancasila which is the nation's ideology as a view of life and the foundation in the activities of society, nation and state is impressed only to be memorized without application, including in the field of law. The quality of the state which is the benchmark for safeguarding the nation's ideology is eagerly awaited to control the implementation of a just law based on the noble values of Pancasila. Pancasila as the basis of the State is based as a source of law in Indonesia. All laws and regulations must be an elaboration of the principles contained in Pancasila. All laws and regulations that are not in accordance with Pancasila, are null and void. Therefore, to be able to understand the accuracy of laws and regulations, it is necessary to understand the concepts, principles and values contained in Pancasila. Pancasila as the basis of the state is implemented to be a legal norm that is compelling, binding and sanctions.

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Performance Evaluation and Dimensioning of Systems through Kernel Estimation

Mathematical Problems in Engineering ◽

10.1155/2011/348262 ◽

2011 ◽

Vol 2011 ◽

pp. 1-20 ◽

Cited By ~ 9

Author(s):

G. M. Gontijo ◽

G. S. Atuncar ◽

F. R. B. Cruz ◽

L. Kerbache

Keyword(s):

Performance Measures ◽

Call Center ◽

Kernel Smoothing ◽

Blocking Probability ◽

Queueing Systems ◽

Real Life ◽

Kernel Estimation ◽

Queue Size ◽

Number Of Customers ◽

Arrival Pattern

We extend the analysis of queueing systems for real-life situations, where the arrival pattern of customers is unknown. In real systems, we must understand how the choice of a method of estimation influences the configuration of the system. Using kernel smoothing, we evaluate algorithms to estimate performance measures of a system, including the invariant probability distribution of the number of customers in the system, the blocking probability, the average queue size, and the average client queue time. We successfully apply the method to the arrivals to a call center to plan and improve the performance of these important queueing systems.

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State-space prediction of soil respiration time series in temperate, semi-arid grassland in northern China

Soil Research ◽

10.1071/sr12068 ◽

2012 ◽

Vol 50 (4) ◽

pp. 293 ◽

Cited By ~ 5

Author(s):

Xiaoxu Jia ◽

Ming'an Shao ◽

Xiaorong Wei

Keyword(s):

Soil Respiration ◽

Surface Temperature ◽

State Space ◽

State Space Model ◽

Soil Surface ◽

Northern China ◽

The State ◽

Soil Surface Temperature ◽

Semi Arid

The prediction of soil respiration (Rs) has traditionally been studied using classical statistical methods. These methods do not consider temporal/spatial coordinates and assume independence between samples. The aim was to determine the primary factors influencing Rs and to develop a state-space model able to predict soil respiration. This study was conducted during one growing season, from July to October 2010, in temperate, semi-arid grassland. Data were collected for Rs, air temperature, soil surface temperature, soil temperature at a depth of 5 cm, soil moisture, air pressure, and relative humidity. Additionally, a novel autoregressive state-space method was used to simulate and predict Rs based on primary factors, and the quality of prediction was compared with the quality of prediction using classical statistics. Soil surface temperature and soil moisture were identified as primary factors affecting Rs. The state-space model that included soil surface temperature was a simple but effective model, accounting for 95% of the variation in Rs. The classical statistical models, however, represented only 39–69% of the variation in Rs. Furthermore, the quality of prediction of the state-space models was consistently much better than the quality from the classical statistical methods. State-space analysis is an effective tool for studying the temporal relationships between soil respiration and influencing factors. Additionally, the state-space method is recommended for predicting soil respiration using soil surface temperature in semi-arid grassland in northern China.

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A New Lumped Parameter Model for Natural Gas Pipelines in State Space

Energies ◽

10.3390/en11081971 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1971 ◽

Cited By ~ 8

Author(s):

Kai Wen ◽

Zijie Xia ◽

Weichao Yu ◽

Jing Gong

Keyword(s):

Natural Gas ◽

State Space ◽

Transient Flow ◽

Transfer Functions ◽

The State ◽

Lumped Parameter Model ◽

Actual Behavior ◽

Gas Pipelines ◽

Computational Point ◽

Lumped Parameter

Many algorithms and numerical methods, such as implicit and explicit finite differences and the method of characteristics, have been applied for transient flow in gas pipelines. From a computational point of view, the state space model is an effective method for solving complex transient problems in pipelines. However, the impulse output of the existing models is not the actual behavior of the pipeline. In this paper, a new lumped parameter model is proposed to describe the inertial nature of pipelines with inlet/outlet pressure and flow rate as outer variables in the state space. Starting from the basic mechanistic partial differential equations of the general one-dimensional compressible gas flow dynamics under isothermal conditions, the transfer functions are first acquired as the fundamental work. With Taylor-expansion and a transformation procedure, the inertia state space models are derived with proper simplification. Finally, three examples are used to illustrate the effectiveness of the proposed model. With the model, a real-time automatic scheduling scheme of the natural gas pipeline could be possible in the future.

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Neutrosophic Event-Based Queueing Model

10.54216/ijns.060103 ◽

2020 ◽

pp. 48-55

Author(s):

Mohamed Bisher Zeina ◽

Keyword(s):

Performance Measures ◽

Waiting Time ◽

Communication Systems ◽

Queueing Systems ◽

Real Life ◽

Main Tool ◽

Expected Number ◽

Mean Waiting Time ◽

Event Based ◽

Number Of Customers

In this paper we have defined the concept of neutrosophic queueing systems and defined its neutrosophic performance measures. An important application of neutrosophic logic in queueing systems we face in real life were discussed, that is the neutrosophic events accuring times, because of its wide applications in networking and simulating communication systems specialy when probability distribution is not known, and because it’s more realistic to consider and to not ignore the imprecise events times. Event-based table of a neutrosophic queueing system was presented and its neutrosophic performance measures were derived, i.e. neutrosophic mean waiting time in queue, neutrosophic mean waiting time in system, neutrosophic expected number of customers in queue and neutrosophic expected number of customers in system. Neutrosophic Little’s Formulas (NLF) were also defined which is a main tool in queueing systems problems to make it easier finding performance measures from each other.

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