• International conference on construction engineering and project management
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• 2011.02a
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• pp.445-452
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• 2011

The schedule hierarchy in construction project is generally composed of three levels. The highest level is a milestone schedule and represented by Bar Chart format. The middle level is an integrated project schedule (IPS) and represented by CPM (Critical Path Method) format. The lowest level is a detail working schedule and usually represented by Bar Chart. The traditional scheduling techniques such as ADM (Arrow Diagramming Method) or PDM (Precedence Diagramming Method) cannot represent all kinds of schedule within schedule hierarchy as identical schedule format. However, the BDM (Beeline Diagramming Method) technique can represent all kinds of schedule within schedule hierarchy as identical CPM format. This paper describes the basic concept, principle, interpretation methods, and schedule computation methods of the BDM as a new networking technique that can represent all kinds of overlapping relationships between activities, and then presents an example of representing three level's schedules within schedule hierarchy by the BDM technique.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.8-13
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• 2017

Nuclear power plant (NPP) constructions are large scale projects that are executed for several years, and schedule control utilizing various schedules is a critically important factor. Recently Korea independently developed the Advanced Power Reactor (APR) 1400 and is building nuclear facilities applying this new reactor type. The construction of Shin-Kori NPP (SKN) Unit 3, which adopted the APR1400, was completed and commercial operation has begun, while, SKN 4, Shin-Hanul NPP (SHN) Units 1&2, and SKN 5&6 are currently under construction. Prior to the development of the APR1400, Korea built 24 reactors and accumulated the schedule data of various reactor types which provided the foundation for schedule reduction to be possible. However, as there is no schedule development and review system established based on the standard schedule data (standard activities, durations, etc.) by reactor type, the process for developing the schedule for new builds is low in efficiency consuming much time and manpower. Also all construction data has been accumulated based on schedule activities. But because the connectivity of activities between projects is low, it is difficult to utilize such accumulated data (causes for schedule delay, causes for design changes, etc.) in new build projects. Due to such reasons, issues continue to arise in the process of developing standard schedule activities and a standard schedule for nuclear power plant construction. In order to develop a standard schedule for NPP construction, i) the development of an NPP standard schedule activity list, ii) development of the connection logic of NPP standard schedule activities, iii) development of NPP standard schedule activity resources and duration, and iv) integration of schedule data need to be performed. In this paper, an analysis was made on the coherence of schedule activity descriptions of existing NPPs by applying the probabilistic methodology on activities with low connectivity due to the utilization of the numbering system of four APR1400 reactors (SHN 1&2 and SKN 3&4).This study also describes the method for developing a standard schedule activity list and connectivity measures by extracting same and/or similar schedule activities.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.3
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• pp.396-402
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• 2018

Earned Value Management(EVM) has been used to manage and forecast defense project schedule and cost over the last two decades in the world. However to support the lacking ability of schedule analysis in traditional EVM, earned schedule(ES) has been introduced as a tool to more accurately estimate schedule performance. This paper compares which method EVM or ES, provides more accurate schedule predictors in 32 Korean defense research and development projects. As a result of comparison, the ES method can predict the future schedule more reliably than the EVM method. We also analyze early warning function of schedule performance index considering project duration extension point. Through the analysis results, we confirm that both the EVM and the ES method lack the ability of the early warning in terms of the current schedule management criterion.

• Journal of the Korean Home Economics Association
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• v.32 no.2
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• pp.49-60
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• 1994

Recently there has been new work schedule developed in some companies which means starting the work at 7 and finishing at 4 This article studied on the effects of new work schedule on the time allocation by married couples. It was compared with the time spent by married couples in group of old work schedule. And it studied whether the change of work schedule affects the time allocation and satisfaction of couples. This survey was conducted from November to December 1993 One hundred and twenty none couples were considered to be valid sample for this study. The findings of this study are as follows: 1. Couples with new work schedule did perceive changes in the time allocation. 2. The total time for transportation and market work of husbands was decreased and leisure time showed a increase when there is new work schedule. 3. Husbands with new work schedule perceived that they spent more time in the household work leisure sharing with their children and sharing with spouses than husbands with old work schedule. 4. Couples with new work schedule showed higher marital satisfaction and family life satisfaction than couples with old work schedule.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.4
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• pp.567-574
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• 2019

Traditional project progress method(PPM) has been used for Korean defense research and development project management for the last 20 years. However, it is difficult to intuitively understand the performance in terms of the project schedule, because the PPM does not provide the function of managing and forecasting project schedule. Therefore, this paper proposes new schedule managing and forecasting function for the PPM using earned schedule management concept. We verify the effectiveness of the proposed functions through several defense projects and prove that it is possible to reinforce the schedule management function of the PPM.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.25-30
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• 2005

This experiment was carried out for the improvement of drying schedules for 50 mm-thick Japanese red pine (Pinus densiflora Sieb. et Zucc.) lumber. Drying rates were analyzed comparatively after drying to 15% of final moisture content through the applications of conventional kiln drying schedule, time schedule, continuously rising temperature schedule, and drying rate schedule. As results drying rate of 50 mm-thick red pine lumber was 0.53%/hr with conventional kiln drying schedule, 0.9%/hr with time schedule, 2.29%/hr with continuously rising temperature schedule, and 1.52%/hr with drying rate schedule, respectively.

• Journal of Internet Computing and Services
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• v.8 no.4
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• pp.105-117
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• 2007

In order to succeed in a bid or development, the project manager should estimate its cost and schedule more accurately in the early stage of the project. Usually, the nominal schedule of most projects can be derived from rule of thumb, first-order estimation practice, or ball-park schedule estimation table. But the rule-of-thumb models for the nominal schedule estimation are so various, and the first-order estimation practice does not provide sufficient information. So they do not help much to decide on the proper development effort and schedule for a particular size of project. This paper presents a statistical regression model for deciding the development effort and schedule of a project using the ball-park schedule estimation table. First, we have redefined such words suggested in the ballpark schedule estimation table as shortest possible schedule, efficient schedule and nominal schedule, Next, we have investigated the relationship between the development effort and the schedule. Finally, we have suggested a model for estimating the development effort and the more accurate schedule of such particular sizes of software as are not presented in the ball-park schedule estimation table. The experimental results show that our proposed regression analysis model decreases the mean magnitude of relative error by 2% at maximum. Also this model can estimated the development effort and schedule for a particular size of software.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.3
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• pp.65-77
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• 1994

There are so many situations in which production schedules need to be rescheduled, due to the uncertainty or dynamic characteristics existing in manufacturing environment. Under the circumstances, it is necessary to build a system which helps a schedule manager understand the dynamic situations and reflect his insight into the system easily. We developed a system that can improve a production schedule. The system consists of a schedule editor and a schedule generator. The schedule editor, a rule-based system, always keeps a schedule feasible by keeping track of local changes in the revised one. The schedule generator consists of a two-phase heuristic method. In the lst phase it generates a schedule by a priority rule with Giffler and Thompson algorithm then it improves the performance in terms of the makespan in the 2nd phase. Experimental results show that, most of the times, the system generates a better schedule than the one with ordinary priority rules only.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.131-136
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• 2006

In constructing projects, there exist various kinds of work interferences, which cause a delay of the outset and completion of planned schedule because of some attributions, such as variability, uncertainty and complexity. and so schedule delay has been treated as a natural phenomenon. To reduce or prevent the schedule delay, a constant confirmation of schedule delay and a preparation of counter plans for finding out the cause structure of schedule delay should have been done. However, all this time the research has been mostly done on the calculation method or claim cases of schedule delay. Moreover, the analysis method did not consider the trait, which cause the schedule delay, in constructing projects. This paper restricts the range of the cause analysis of schedule delay to the field of site management in the projects and divides the cause structure of schedule delay into the cause objects and cause attributes of schedule delay according to the input elements. The system of classifying causes of schedule delay is examined by interviews with experts and questionnaire. Additionally, this paper analyzes the attributes of cause attributes and cause subjects and presents the analysis method and procedure of schedule delay with the application of VSM.

• IE interfaces
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• v.11 no.3
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• pp.129-141
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• 1998

In this paper, a rescheduling procedure is developed for shipbuilding master production schedule. Shipyard initially develops backward production schedules for the entire shipbuilding process, and then refines the schedule by stage. The rescheduling procedure of this paper tries to resolve the schedule discrepancies between the outdoor backward schedule and the refined indoor schedule. Through the proposed rescheduling procedure, outdoor schedule can be successfully adjusted using buffer days and duration reduction. An Object-oriented program is also developed to automate the procedure. We can observe the improvement on productivity and quality of rescheduling works from the application of the developed procedure.