scholarly journals Models, describing vehicles processing on offshore terminals

2020 ◽  
Author(s):  
Ю.В. Горгуца
Keyword(s):  
Service Time ◽  
Statistical Data ◽  
Service Systems ◽  
Weather Factors ◽  
Time Intervals ◽  
Final Model ◽  
Channel One ◽  
Basic Model ◽  
Mass Service ◽  
Random Events

При проектировании рейдовых причалов, строительство которых получило широкое развитие в настоящее время, невозможно воспользоваться методами, предлагаемыми ныне действующими Нормами технологического проектирования, так как они были выполнены для традиционных защищённых акваторий и опираются на статистический материал, полученный по существующим портам. Для разработки методов определения простоев судов при обработке судов на рейдовых причалах с учётом потока помех от метеофакторов (штормов) как потока случайных событий в данной статье описывается исследование новых моделей систем массового обслуживания. Используется метод суперпозиций – находятся решения для простых моделей, которые затем используются для получения решений по более сложным моделям. Первоначально рассматривается простейшая модель, состоящая из потоков вызовов (штормов) и прибора (порта). Поток вызовов - пуассоновский. Время обслуживания – произвольное с преобразованием Лапласа-Стилтьеса Полученные результаты используются для исследования модели с потоками помех от ветров двух различных направлений. Далее исследуется однолинейная модель с «ненадёжным» прибором. Входящий поток – пуассоновский поток подходящих к порту судов. Время обслуживания - длительность интервалов времени между освобождением места у причала для судна, ожидающих на рейде. Выход из строя прибора, как в свободном, так и в занятом обслуживанием состоянии определяется наступлением шторма – событием пуассоновского потока с интервалами между событиями – интервалами между наступлением штормов. Длительность восстановления работоспособности прибора – определяемая в первой модели длительность простоя причала из-за воздействия метеофакторов. Суда, оказавшиеся в порту при наступлении шторма «дообслуживаются» после его окончания Итоговая модель – многоканальная с параллельно работающими приборами (причалам) и экспоненциальным временем обслуживания судов. Полученные результаты сравнивались со статистическими и показали их высокую сходимость, что доказывает их достоверность. While designing offshore terminals, which are being built quite widely in recent time, it is impossible to use methods, proposed by current technological design norms, because they were created for traditional protected waters and are based on statistical data, acquired by existing ports. This article describes the research of new models of mass service systems to develop methods of defining demurrage while processing vehicles on offshore terminals, taking into account disturbance flow from weather factors (storms) as flow of random events. Method of superpositions is used - to find solutions for simple models, which are used afterwards for getting solutions for more complicated models. Initially the basic model is reviewed, consisting of flow of challenges (storms) and device (port). Challenges flow is Poisson. Service time - arbitrary with transformation of Laplace-Stiltjes. Results acquired are used for researching the model with disturbance flows from windows of various directions. Next the unilineal model with “unreliable” device is researched. Incoming flow is Poisson flow of incoming vehicles. Service time - length of time intervals between berths exemption for vehicles awaing on raid. Device failure, both in free and in maintenance mode was defined by storm incoming - the event of Poisson flow with intervals between events - intervals between storms. Duration of device efficiency recovery - is the defined in the first model duration of terminal demurrage due to weather influence. Vessels, caught up in the port during storm will be maintained after its end. Final model is multi-channel one with working devices (terminals) and exponential time of vessel service. Acquired results have been compared with statistical data, which showed they high convergence, proving their reliability.

Markov chains governed by complicated renewal processes

1970 ◽  
Vol 2 (02) ◽  
pp. 287-322
Author(s):  
T. Gergely ◽  
I. N. Tsukanow ◽  
I. I. Yezhow
Keyword(s):  
Markov Chains ◽  
Sojourn Time ◽  
Practical Importance ◽  
Service Systems ◽  
Independent Random Variables ◽  
Renewal Processes ◽  
Time Intervals ◽  
Mass Service ◽  
Fixed Region ◽  
Mutually Independent

In this work Markov chains governed by complicated processes are introduced and investigated (Section 1). In Section 2 an ergodic theorem for these processes is formulated, while in Section 3 the sojourn time of the process in a fixed region is studied; in Section 4 some examples are considered. The processes studied are of practical importance in the description of mass service systems and the theory of reliability for which the time intervals between successive demands cannot be assumed to be mutually independent random variables. It is shown that the dependence parameter r of these processes, if it is sufficiently large, allows us to formulate a relationship between the time intervals in question.

SIMULATION MODELING AS AN APPROACH IN SOLVING THE PROBLEMS OF MASS SERVICE SYSTEMS

2020 ◽  
Vol 4 (26) ◽  
pp. 35-44
Author(s):  
V. E. Taratun ◽  
◽  
V. S. Shaperova ◽  
Keyword(s):  
Key Words ◽  
Simulation Modeling ◽  
Statistical Data ◽  
Queuing System ◽  
Service Systems ◽  
Passenger Traffic ◽  
Mass Service ◽  
Complex Technical Systems ◽  
Technical Systems

The article studies the queuing system using the example of Pulkovo airport. The statistical data characterizing the growth of passenger traffic are presented. The problems of the queuing system and the method of its solution through the use of simulation are considered. Key words: simulation modeling, passenger traffic, throughput, CMO, complex technical systems, forecasting.

Markov chains governed by complicated renewal processes

1970 ◽  
Vol 2 (2) ◽  
pp. 287-322 ◽  
Author(s):  
T. Gergely ◽  
I. N. Tsukanow ◽  
I. I. Yezhow
Keyword(s):  
Markov Chains ◽  
Sojourn Time ◽  
Practical Importance ◽  
Service Systems ◽  
Independent Random Variables ◽  
Renewal Processes ◽  
Time Intervals ◽  
Mass Service ◽  
Fixed Region ◽  
Mutually Independent

In this work Markov chains governed by complicated processes are introduced and investigated (Section 1). In Section 2 an ergodic theorem for these processes is formulated, while in Section 3 the sojourn time of the process in a fixed region is studied; in Section 4 some examples are considered. The processes studied are of practical importance in the description of mass service systems and the theory of reliability for which the time intervals between successive demands cannot be assumed to be mutually independent random variables. It is shown that the dependence parameter r of these processes, if it is sufficiently large, allows us to formulate a relationship between the time intervals in question.

scholarly journals Imitating modeling of mass service systems

2019 ◽  
Vol 6 (4) ◽  
Author(s):  
Vera Yudanova
Keyword(s):  
Statistical Data ◽  
Single Channel ◽  
Discrete Event ◽  
Main Tool ◽  
Service Systems ◽  
Queuing Systems ◽  
Visual Models ◽  
Mass Service ◽  
Event Model ◽  
Object Oriented Approach

The theory of мass service systems is applied in many areas of human activity – economy, strategic tasks, computer science and technology, problems of natural science, etc. Analytical methods for the study of mass service systems allow you to get only a set of certain characteristics of the parameters of the object under study. Imitating modeling methods make it possible not only to build visual models of the functioning of complex systems with any degree of detail, but also to implement various types of computational algorithms for data processing and analysis. The theoretical aspects of the use of imitating models in the theory of mass service are described in the literature extensively, but not systematically, the issues of using modern software and computing tools in modeling problems of such systems are presented only by a few sources. In this article the author reveals introductory questions in the use of the concept of discrete-event type of imitating modeling as the main tool of research of discrete objects with stochastic character of functioning. A comparison is made of elements of queuing systems and components of a discrete event model. The examples of solving practical tasks on modeling single-channel and multi-channel queuing systems examine the capabilities of the Anylogic imitating modeling environment: a process modeling library with the ability to collect and present statistical data, programming elements to expand the model’s functionality, implement an object-oriented approach in the structure of the model itself and in the tools of the developer. The imitating modeling results are analyzed using an simple experiment in Anylogic as an example.

On the distribution of the number of cyclically occurring random events

1972 ◽  
Vol 9 (3) ◽  
pp. 681-683
Author(s):  
Leon Podkaminer
Keyword(s):  
Random Variables ◽  
Independent Random Variables ◽  
Time Intervals ◽  
Time Period ◽  
Random Events ◽  
Mutually Independent

The probabilities of the occurrence of n events in a certain time period are calculated under the assumptions that the time intervals between the neighbouring events are mutually independent random variables, satisfying some analytic conditions.

scholarly journals MODELING OF THE OPERATIONAL SITUATION IN THE EXCLUSION ZONE

2020 ◽  
Vol 1 (1) ◽  
pp. 42-51
Author(s):  
A Tsyhankov ◽  
V Nizhnyk ◽  
Y Feshchuk ◽  
O Teslenko ◽  
Yа Ballo
Keyword(s):  
Service Time ◽  
Emergency Service ◽  
Statistical Data ◽  
The State ◽  
Empirical Dependence ◽  
Exclusion Zone ◽  
Fire Station ◽  
Service Areas ◽  
Normative Response ◽  
Definition Of

The urgency of the work is due to the objective dynamics of changes in the level of man-made and natural threats in the exclusion zone and unconditional (compulsory) resettlement, increasing the volume of taskssolved by operational and rescue units of the State Emergency Service of Ukraine, the need for security people who are, work and live in the Exclusion Zone. Potential threats and dangers in the exclusion zone and unconditional (compulsory) resettlement have been identified. The analysis of statistical data on the involvement of fire and rescue equipment for firefighting. The empirical dependence of the involvement offire and rescue equipment of the State Emergency Service of Ukraine on the elimination of fires in the exclusion zone during the year on their number has been established. It was found that most often 4 to 7 units of fire and rescue equipment of the State Emergency Service of Ukraine are involved in extinguishing fires. Based on the processing of numerical analysis of statistical data, the following conclusions were made: 95% of the time during the year, fire and rescue units are on duty (without calls); 438 hours a year put out single fires; Two hours a year, two fires are extinguished simultaneously. The analysis of calls by service time is carried out. It is established that the service time of calls of fire and rescue units in 25% of cases is up to 2 hours and in 22% of cases is 7-8 hours. An assessment of the locations of fire and rescue units and forest posts with the definition of their service areas. As a result of calculations, it was established that to ensure the normative response to fires at existing facilities in the exclusion zone, it is necessary to provide 4 additional locations of forces and means of fire and rescue units, as well as to ensure the functioning of the fire station on the Vector complex. 

scholarly journals Simulation model of situational control of transshipment machinery fleet

2019 ◽  
Vol 135 ◽  
pp. 02028
Author(s):  
Igor Zub ◽  
Yuriy Ezhov ◽  
Viktor Shchemelev
Keyword(s):  
Simulation Model ◽  
Petri Nets ◽  
Service Time ◽  
Statistical Data ◽  
Stochastic Nature ◽  
Conflict Situations ◽  
Short Period ◽  
Situational Management ◽  
And Storage

The seaport is a place for cargo transshipment and storage. The speed of vehicle processing is one of the indicators of port’s performance. The time of vehicles being under processing depends on the performance of a fleet of transshipment machinery. The stochastic nature of vehicles’ arriving leads to the intense operation of handling facilities and formation of wait lists for vehicles to be loaded or unloaded, or to the downtime of transshipment machinery when vehicles are absent. Depending on the operational situation, transshipment machinery is brought out for maintenance operations that can be performed by unit, which provides the increase in the technical use coefficient. For maintenance of individual units, the decomposition of handling facility is performed; statistical data on the time of maintenance conduction for all units is collected. Statistical data are entered into the database. When transshipment machinery is brought out of operation for a short period, the unit is selected, the service time of which coincides with the downtime of a brought out facility. To visualize the process of situational management of maintenance and define conflict situations, a simulation model was developed with the use of the apparatus of Petri nets. The analysis of the model helped to reveal conflict situations that can be solved both during situational management of transshipment machinery fleet and by means of models nested into conflict places.

scholarly journals Spectral Analysis in Solving Problems of Managing Accident Rate in Aviation

2015 ◽  
Vol 4 (6) ◽  
pp. 12-16
Author(s):  
Попов ◽  
Yuriy Popov ◽  
Куменко ◽  
A. Kumenko
Keyword(s):  
Spectral Analysis ◽  
Management System ◽  
Statistical Data ◽  
Safety Management ◽  
Flight Safety ◽  
Accident Rate ◽  
Time Intervals ◽  
Aviation Accidents ◽  
Management Structure ◽  
Relative Safety

Based on the analysis of statistical data on the number of aviation accidents per 100 thousand flight hours for the period of 1960-2012, the article proposes the use of periodogram as a method of spectral analysis to detect cycles and determine whether there is any indication of flight safety management system at different time intervals. It shows that strategic influences on safety system (within stable and well-functioning management structure) directly and extensively shape the trend of relative safety indicator.

On the distribution of the number of cyclically occurring random events

1972 ◽  
Vol 9 (03) ◽  
pp. 681-683
Author(s):  
Leon Podkaminer
Keyword(s):  
Random Variables ◽  
Independent Random Variables ◽  
Time Intervals ◽  
Time Period ◽  
Random Events ◽  
Mutually Independent

The probabilities of the occurrence of n events in a certain time period are calculated under the assumptions that the time intervals between the neighbouring events are mutually independent random variables, satisfying some analytic conditions.

Does the Gamma Distribution Refer to an Underlying Mechanism in Binocular Rivalry?

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 22-22 ◽  
Author(s):  
P H C Vallen ◽  
P R Snoeren ◽  
Ch M M de Weert
Keyword(s):  
Distribution Function ◽  
Gamma Distribution ◽  
Binocular Rivalry ◽  
Waiting Times ◽  
Underlying Mechanism ◽  
Stimulus Strength ◽  
Time Intervals ◽  
Neural Spikes ◽  
Random Events ◽  
Process Speed

Thirty years ago, Levelt (1967 British Journal of Psychology58 143 – 145) fitted the distribution of dominance times in binocular rivalry with the gamma distribution (the distribution function of waiting times for N random events with process speed lambda). Ever since, the gamma distribution has been used to describe the rivalry phase durations, without an explanatory underlying mechanism being given. Although Levelt suggested lambda to be proportional to the stimulus strength (eg contrast, luminance, blur, amount of contour) and N to be ‘successive neural spikes’, this suggestion has never been tested. The purpose of this study was to test whether or not N and lambda represent characteristics of the observer and the stimulus, respectively. To collect the data as accurately as possible, we performed a large number of measurements involving different designs and stimuli. In contrast to previous experiments, collected data were not pooled but were compared within each subject. We tested the hypothesis by collecting time intervals from subjects responding to numerous conditions in which disk - ring stimuli were varied in contrast, blur, or amount of contour in one eye.

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