• Communications of the Korean Mathematical Society
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• v.28 no.2
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• pp.383-396
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• 2013

We consider an M/PH/1 queue with deterministic impatience time. An exact analytical expression for the stationary distribution of the workload is derived. By modifying the workload process and using Markovian structure of the phase-type distribution for service times, we are able to construct a new Markov process. The stationary distribution of the new Markov process allows us to find the stationary distribution of the workload. By using the stationary distribution of the workload, we obtain performance measures such as the loss probability, the waiting time distribution and the queue size distribution.

• IE interfaces
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• v.25 no.2
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• pp.196-203
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• 2012

In the postal delivery service, both the standardization of business process and the workload measurement is very important part of saving the cost and improving the efficiency. However, these are not easy to apply to real situation because of the labor-intensive and diversification of delivery environment. In this study, we develop the methodology for the standardization of business process and workload measurement model of the postal delivery service. Firstly, we introduce the work factor analysis on the postal delivery process. Then, we propose the methodology workload measurement model based on diversification of delivery environment.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1362-1366
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• 2003

Workload programming is allocating suitable workloads of production process according to the needs of products, which would minimize the total cost of both work and stock under some constraint conditions. In this paper, a production process flow chart of discrete manufacturing is presented by a Petri net, and the optimization model of workload-stock is established. An approach of the optimal workloads is provided by means of the integer matrix theory. An example is given to verify this method.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.05a
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• pp.135-144
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• 1999

A major concern in Concurrent Engineering is the control and management of workload in a period of process. As a general rule, leveling the peak of workload in a certain period is difficult because concurrent processing is comprised of various processes, including overlapping, paralleling and looping. Therefore, workload management with resource constraints is so beneficial that effective methods to analyze design process This study presents a procedure to transform the IDEF3 process model into the precedence logic network model for more useful assessment of the process. This approach is expected to facilitate resolving resource constrained scheduling problems more systematically in Concurrent Engineering environment.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.11
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• pp.461-470
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• 2013

This paper proposes high speed kernel data collection method for analysis of memory workload, using technique of direct access to process's memory management structure. The conventional analysis tools have a slower data collection speed and they are lack of scalability due to collection only formalized memory information. The proposed method collects kernel data much faster than the conventional methods using technique of direct collect to process's memory information, page table, page structure in the memory management structure, and it can collect data which user wanted. We collect memory management data of the running process, and analyze its memory workload.

• IE interfaces
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• v.9 no.3
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• pp.257-268
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• 1996

This paper illustrates the process of developing and configuring the prototype Computer Analysis System for Controlling Occupational WORKload (CAS-COWORK). The software interface between the database and expert system was attempted. The database is used for storing and retrieving series of data entered by general users and the expert system is used for identifying and solving occupational problem areas. Two theories were applied in developing the algorithm base of CAS-COWORK that were used to calculate overall workload stress level. The fuzzy set theory was introduced to capture the subject‘s workload stress perception. The Analytic Hierarchy Process (AHP) was introduced to estimate the importance of the task and workplace variables. The purpose of the system development is for future prediction and problem solving which would be highly valuable to the industrial engineer.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.30
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• pp.25-34
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• 1994

Mental workload has a improtant place in modern work environment such as human-computer interaction. Designing man-machine system requires knowledge and evaluation of the human cognitive process which controls information flow during our works. Many studies estimate reaction time as a index of menatal workload. This paper investigates what reflacts the workload of human information handling when the informations grow its degree. Experiment result introuce the memory time that explain the information-load more sensitive than react time. And react time shows learning effect but memory time does'nt show that effect So it can be concluded that cognitive learning or work schema needs more time to achieve dexterity than motor skill.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.231-240
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• 1999

A major concern in Concurrent Engineering is the control and management of workload in a period of process. As a general rule, leveling the peak of workload in certain period is difficult because concurrent processing is comprised of various processes, including overlapping, paralleling looping and so on. Therefore, the workload management with resource constraints is so beneficial that effective methods to analyze design process are momentous. This study presents the Timed Petri Nets approach of precedence logic networks, and provides an alternative for users to analyze constraint processes to resolve conflicts of resources. Another approach to Continuous Time Markov Chain using Stochastic Petri Nets is also proposed. These approaches are expected to facilitate resolving resource constrained scheduling problems more systematically in Concurrent Engineering environment.

• Journal of Korea Society of Industrial Information Systems
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• v.21 no.6
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• pp.1-12
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• 2016

In this paper, we consider a general discrete-time queueing system with D-BMAP(discrete-time batch Markovian arrival process) and D-policy. An idle single server becomes busy when the total service times of waiting customer group exceeds the predetermined workload threshold D. Once the server starts busy period, the server provides service until there is no customer in the system. The steady-state workload distribution is derived in the form of generating function. Mean workload is derived as a performance measure. Simulation is also performed for the purpose of verification and a simple numerical example is shown.

• Journal of radiological science and technology
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• v.45 no.3
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• pp.213-223
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• 2022

Although the number of computed tomography(CT) is increasing every year, it is insufficient to establish appropriate workload calculation standards of radiologic technologist to provide optimal medical services to patients, such as patient safety management and infection management. The purpose of this study is to present guidelines for calculating the appropriate workload of radiologic technologist by analyzing the work flow of CT procedures and the time required for CT examination in major hospitals. As for the study subjects and methods, the appropriate process for each step of CT examination was investigated to systematically present the process and time required for the actual examination, and the CT procedure time of 104,105 adult patients and 465 pediatric patients under the age of 6 were analyzed. For the time required, data according to the use of contrast medium, procedure type, and adult/child were collected and compared. The test time of CT examination using contrast medium took about 13 minutes when one radiologic technologist worked and about 9 minutes when two radiologic technologists worked. The time required for the procedures were statistically significant depending on the presence or absence of contrast medium, multi-phase procedure, and patient age (considering pediatric patients). As a result, in order to thoroughly perform patient safety and infection management, the appropriate workload increased by about 40% when there were two radiologic technologists. The limit workload was an average of 32 people per day with one radiologic technologist per 15 minutes, and 48 people per day with two radiologic technologist per 10 minutes. This is a marginal workload, and in the case of procedures that require more time to acquire radiographic images, the interval between reservations should be widened.