• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2009.05b
• /
• pp.163-166
• /
• 2009

All sorts of technique for schedule progress management is being developed recently, These can change and develop the abstractive concept model to a detailed model that describes the visual 3D image about a schedule plan. but, this technique is troublesome, because this requires the handwork by means of connection between 3D-CAD and scheduling Program. In this study, the process of real-time schedule progress control system using the integrated database by 3D-CAD object information system and schedule module is presented. This study present the process of a schedule progress management using UML, and the process of real-time schedule progress management using RFID system. Through this study, we want to realize the rapid generation of estimated schedule information and to simulate and analyze actual schedule information by real-time.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.400-408
• /
• 2009

Simulation applications for analyzing the productivity of construction operations at operation level and project schedules at project level are crucial methods in project management. The application at two different levels should be very tightly linked to each other in practice. However, appropriate integration at the levels is not achieved in that existing systems do not support to integrate operation models into a schedule model. This paper presents a new approach named to Discrete Event Simulation-Nesting modeling approach, which supports not only productivity analysis at operation level but also schedule management at a project level. The system developed by the authors allows creating operation models at the operation level, maintaining them in operation model library, executing sensitivity analysis to find the behaviors of the operation models when different combination of resources are used as existing DES systems do. On top of the conventional functions, the new system facilitates to find the optimum solution of resource combinations which satisfy the user's interest by computing the hourly productivity and the hourly cost of the operation. By drag-and-dropping an operation model kept in the operation model library, the operation models are integrated into an activity of the schedule model. When a complete schedule model is established by nesting operation models into the schedule model, stochastic simulation based scheduling is executed. A case study is presented to demonstrate the new simulation system and verify the validity of the system.

• Journal of the Korea Institute of Building Construction
• /
• v.11 no.1
• /
• pp.1-8
• /
• 2011

Linear scheduling method limits to present works of work breakdown structure as a form of lines and was often developed manually. In other words, linear schedule could not utilize activity, work breakdown structure, and etc. information of network schedule such as CPM(Critical Path Method) and has been used only for reporting or confirming construction master plan. Therefore, it is necessary to develop system which can automatically generating the linear schedule based on the network schedule having many accumulated and useful construction schedule information. Thus, this research has an effort to establish data process model, data flow diagram, and data model in order to make linear schedule. In addition, this research addresses the system solution structure, user interface class diagram and logic diagram, and data type schema. The results of this paper can be used as a preliminary research for developing linear schedule generating system prototype by utilizing the network schedule information.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.2
• /
• pp.33-44
• /
• 2022

The simulation function by the 4D system is a representative BIM function in the construction stage. For the 4D simulation, schedule information for each activity must be created and then linked with the 3D model. Since the 3D model created in the design stage does not consider schedule information, there are practical difficulties in the process of creating schedule information for application to the construction stage and linking the 3D model. In this study, after extracting the schedule information of the construction stage using the HDBSCAN algorithm from the 3D model in the design stage, authors propose a methodology for automatically generating schedule information by identifying precedence and sequencing relationships by applying the topological alignment algorithm. Since the generated schedule information is created based on the 3D model, it can be used as information that is automatically linked by the common parameters between the schedule and the 3D model in the 4D system, and the practical utility of the 4D system can be increased. The proposed methodology was applied to the four bridge projects to confirm the schedule information generation, and applied to the 4D system to confirm the simplification of the link process between schedule and 3D model.

• Journal of the Korea Institute of Building Construction
• /
• v.10 no.4
• /
• pp.31-39
• /
• 2010

As the linear scheduling method has been used since the Empire State Building linear schedule in 1929, it is being applied in various fields, such as construction and manufacturing. When addressing concurrent critical paths occurring in a linear construction schedule, empirical researches have stressed resource management, which should be applied for optimizing workflow, ensuring flexible work productivity and continuous resource allocation. However, work relationships have been usually overlooked in making the linear schedule from an existing network schedule. Therefore, this research analyzes the previous researches related to the linear scheduling model, and then proposes a method that can be applied for adopting the relationships of a network schedule to the linear schedule. To this end, this research considers the work relationships occurring in changing a network schedule into a linear schedule, and then confirms the activities movement phenomenon of linear schedule due to workspace change, such as physical floors change. As a result, this research can be used as a basic research in order to develop a system generating a linear schedule from a network schedule.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.11
• /
• pp.5890-5896
• /
• 2013

This Study aimed at suggesting the plan for accumulating and utilizing schedule information of IFC file in BIM-based delivery system. For this Propose, First, literature review is conducted for analyzing utilization plan of schedule information and the IFC standard. Second, Schedule Planning process is analyzed to draw Schedule elements, and schedule information items is derived by analyzing schedule process and commercial software. Also, schedule elements in the IFC schema is derived by analyzing IFC schema through drawn schedule information. Finally, this study suggests a concept model accumulating and utilizing Schedule information included in IFC schema, and a conceptual delivery process of BIM model by analyzing BIM Application Guideline for Facility Project by PPS (Public Procurement Service) for accumulating IFC delivery files This study will expects to contribute to accumulate information of BIM model at the point of nationally introducing BIM.

• Journal of Construction Engineering and Project Management
• /
• v.3 no.2
• /
• pp.21-34
• /
• 2013

Various risk factors affect construction projects. Due to the uncertainties created by risk factors, actual activity durations frequently deviate from the estimated durations in either favorable or adverse direction. For this reason, evaluation of schedule uncertainty is required to make decisions accurately when managing construction projects. In this regard, this paper presents a new computer simulation model - the Repetitive Schedule Risk Analysis Model (RSRAM) - to evaluate unit-based repetitive building project schedules under uncertainty when activity durations and risk factors are correlated. The proposed model utilizes Monte Carlo Simulation and a Critical Path Method based repetitive scheduling procedure. This new procedure concurrently provides the utilization of resources without interruption and the maintenance of network logic through successive units. Furthermore, it enables assigning variable production rates to the activities from one unit to another and any kind of relationship type with or without lag time. Details of the model are described and an example application is presented. The findings show that the model produces realistic results regarding the extent of uncertainty inherent in the schedule.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.36 no.3
• /
• pp.27-43
• /
• 2011

This paper investigates properties of the newsvendor problem under a schedule involving progressive multiple discounts compared with the standard newsvendor problem under a no-discounts schedule. Unlike most conventional approaches using the criticial fractile to analyze the retailer and/or supplier behavior(s) in the newsvendor problem, our approach uses riskless profit. From the properties revealed through a series of computational experiments, two conjectures regarding the relationship between the expected profits of both newsvendor problems as a generalization over Khouja's argument (1995) are raised. Those conjectures encourage newsvendors who may face budget or warehouse capacity restriction to use the extended model under a multiple-discounts schedule rather than the standard model with no-discounts schedule because they apply for every order quantity as well as the optimal order quantity. In addition to the conjectures, some insightful results are found to justify the implementation of a multiple-discounts schedule from the computational experiments and a new interpretation for implementation of a multiple-discounts schedule that has not been addressed in Khouja is provided.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2004.08a
• /
• pp.163-172
• /
• 2004

A fast, accurate model for calculating roll gap variables are critical to the implementation of computer based automation systems for cold rolling mills. Based on the work of Fleck and Johnson, rollgap simulator with non-circular arc model was developed using the influence function. This developed model is capable of predicting values of force, torque and slip which can be applied over the wide range of rolling conditions including cold rolling/DR/temper mill with high execution speed. Friction coefficient was obtained as a function of operation conditions through analyzing measured data. After combination of rollgap simulator with production strategy, draft schedule for No.3 RCM (Reversible Cold Rolling Mill) in Incheon works of Dongbu Steel was developed. This draft schedule will be installed in the setup computer of No.3 RCM replacing old Hitachi model.

• Information Systems Review
• /
• v.6 no.2
• /
• pp.195-208
• /
• 2004

In this paper we propose a new software project development management model incorporating quality management to schedule management. Though many efficient techniques such as code review and inspection are used to remove defects, the effect of defect removal time on project schedule hasn't been studied much. However, poor quality management has an important effect upon overall schedule and sometimes software projects fails due to it. Thus, quality management and schedule management should be considered together and we need to reflect the time to maintain software quality into the schedule management. For the proposed model we introduced "Quality Value" representing the needed time to remove software defects. We assume PSP/TSP to gather the needed data for quality value. The proposed model can be used to predict the effect of software defects on schedule in advance and to prevent schedule lag.