• Design & Manufacturing
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• v.14 no.3
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• pp.8-16
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• 2020

In this study, the vibration signal of the mold was measured and analyzed to monitoring the process time and characteristics during injection molding. A 5 inch light guide plate mold was used to injection molding and the vibration signal was measured by MPU6050 acceleration sensor module attached the surface of fixed mold base. Conditions except for injection speed and packing pressure were set to the same value and the change of the vibration signal of the mold according to injection speed and packing pressure was analyzed. As a result, the vibration signal had a large change at three points: "Injection start", "V/P switchover", and "Packing end". The time difference between "injection start" and "V/P switchover" means the injection time in the injection molding process, and the time difference between "V/P switchover" and "Packing end" means the packing time. When the injection time and packing time obtained from the vibration signal of the mold are compared with the time recorded in the injection molding machine, the error of the injection time was 2.19±0.69% and the error of the packing time was 1.39±0.83%, which was the same level as the actual value. Additionally, the amplitude at the time of "injection start" increased as the injection speed increased. In "V/P switchover", the amplitude tended to be proportional to the pressure difference between the maximum injection pressure and the packing pressure and the amplitude at the "packing end" tended to the pressure difference between the packing pressure and the back pressure. Therefore, based on the result of this study, the injection time and packing time of each cycle can be monitored by measuring the vibration signal of the mold. Also, it was confirmed that the level and trend of process variables such as the injection speed, maximum injection pressure, and packing pressure can be evaluated as the change of the mold vibration during injection molding.

• Journal of the Korea Safety Management & Science
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• v.6 no.1
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• pp.97-108
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• 2004

This Study will introduce the concept of A TP(A vailable To Promise) and CTP(Capable to Promise) through the existing study, the process analysis of CTP, the modeling of algorithm and the embodiment of system. This research considers the environment of using Job-Shop method. The CTP algorithm models using LPST(Latest Possible Start Time) and EPST(Earliest Possible Start Time) method especially. It is important part of executing CTP systems. The CTP modeling and implementing develops to system which is capable to implement in the various business environment through additional and continuous research.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1003-1007
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• 1987

The system start-up function of TDX-1A that should be executed during installation or emergency has been designed to meet requirements of the distributed real time control system. It is performed in a centralized manner by the dedicated processor according to the maintenance and administration mechanism of the system. Upon execution, it provides information on the system state for the ESS personal. In additions, it protects the loss the charging and statistics data, and minimizes the effect on the customer service. This paper describes the design concept of the system startup function and its implementation method and also calculates its the execution time.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.141-147
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• 2016

Background: A project for building a neutron time-of-flight (nTOF) facility is progressing. We expect that the construction will start in early 2016. Before that, a detailed simulation based on the current architectural drawings was performed to optimize the performance of our facility. Materials and Methods: Currently, several parts had been modified or changed from the original design to reflect requirements such as the layout of the electron beam line, shape of the vacuum chamber producing a neutron beam, and the underground layout of the nTOF facility. Detailed analysis for these modifications has been done with MCNP simulation. Results and Discussion: An overview of our photo-neutron source and KAERI nTOF facility were introduced. The numerical simulations for heat deposition, source term, and radiation shielding of KAERI nTOF facility were performed and the results are discussed. Conclusion: We are expecting that the construction of the KAERI nTOF facility will start in early 2016, and these results will be used as basic data.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.121-130
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• 2004

This Study will introduce the concept of CTP(Capable-to-Promise) Algorithm, CTP process, and the modeling of algorithm. This research is based on the environment of using Job-Shop method. CTP algorithm model use LPST(Latest Possible Start Time) and EPST(Earliest Possible Start Time) method especially. It is important part of executing CTP system. The CTP modeling and implementing develops to system which is able to implement in the various business environment through additional and continuous research.

• Proceedings of the Safety Management and Science Conference
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• 2003.11a
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• pp.117-127
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• 2003

This Study will introduce the concept of ATP(Available To Promise) and CTP(Capable to Promise) through the existing study , the process analysis of CTP(Capable to Promise), the modeling of algorithm and the embodiment of system. This research considers the environment of using Job-Shop method. The CTP algorithm models espicially through using LPST(Latest Possible Start Time) and EPST(Earlist Possible Start Time) method. It is important part of executing CTP(Capable to Promise), The CTP(Capable to Promise) modeling and implementing system develops to system which is capable to implement in the various business environment through addational and continuous research.

• The KSFM Journal of Fluid Machinery
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• v.11 no.3
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• pp.50-55
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• 2008

The diverter system is a key component in achieving a high accuracy liquid flow rate standard using a static gravimetric system with a flying start and stop method. The diverter is a moving device used to direct flow alternately along its normal course(by pass) or towards the weighing tank. The time needed for collection into the weighing tank is measured using a timer. So it is important to the diversion period is sufficiently fast and triggering point of timer which is determined the filling time. On this studies show that uncertainty of diverter system for changing diversion speed and triggering point was estimated in accordance with Guide to The Expression of Uncertainty in Measurement(ISO).

• International conference on construction engineering and project management
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• 2011.02a
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• pp.468-473
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• 2011

The goal of a project manager is generally to minimize the cost of the project and also to cope with uncertainty. This paper deals with the problem of project scheduling a set of activities satisfying precedence constraints in order to minimize the sum of the costs associated with the starting times of the activities in the network with imprecise activity durations, represented by means of interval or fuzzy numbers. So far this problem has been completely solved by several authors when the activities durations have crisp values. However, they do not consider the imprecision in activity durations in their models. Here the framework of possibility theory is proposed to solve this problem. In fuzzy arithmetic, usually, the interval calculations are used for the aim of complexity reduction and simplification. Thus the case of interval-valued durations is first addressed, and then extended to fuzzy intervals. A numerical example is used to illustrate the developed concept.

• IE interfaces
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• v.4 no.1
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• pp.47-61
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• 1991

This paper develops MRP system with two-types of lead time(average lead time and emergent lead time). In this proposed MRP system, Material Requirement Planning is scheduled by using average lead time, but the emergent lead time is used only when start date of planned order is past. Btrieve data management technique and Stack structure are used for recalculating procedure of planned order with the TURBO PASCAL Version 5.5. An example is also considered.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.1-14
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• 2021

Innovation and Scale-up of Start-up companies are becoming important national tasks. In the past, it was spread the start-up policy paradigm such as 'Start-up America', 'Start-up Chile', 'Start-up Britain' to overcome the recession globally. However as the economic recovery has become more visible recently in advanced economies, it is shifting from a start-up support policy to a scale-up oriented policy paradigm such as 'Scale-up America', Scale-up UK', 'Scale-up Denmark'. It is necessary to enter the scale-up phase beyond the start-up phase to increase the number of high-quality jobs and to continue economic growth. Therefore, it is necessary to grow the start-up into a strong medium-sized company and to lay the foundation for survival. Therefore, the purpose of this study is to consider the antecedent factors that influence the scale-up aspiration for the start-up firm to grow into a scale-up company, and empirically identifies the differences between the stages of economic development and entrepreneurs in the country. In order to accomplish the purpose, this study predicted scale-up by aspiration which is a predictor of scale-up behavior because it is difficult to achieve visible growth in a short period of time due to the characteristics of start-up companies. In order to empirically explore these relationships, the data were collected from nascent entrepreneurs who have less than 3.5 years of the Adult Population Survey(APS) among the subjects surveyed by the Global Entrepreneurship Monitor(GEM) and the national economic development stage are divided into Innovation-driven, Efficiency-driven, Factor-driven type economies. For the test hypotheses, this study adopted the multi-level model analysis for comparison between national economic development stages and using the R 3.5.0 program. The results of this study are as follows. There is difference between the national economic development and the entrepreneur in the relationship between innovation orientation of entrepreneurs and scale-up aspirations. As the economy of the country develops, the innovation activity of the entrepreneur becomes more active. Since start-ups are heavily influenced by entrepreneurs, there is a difference in the degree of aspiration depending on how innovative an entrepreneur is in the same environment. In terms of the relationship between innovation orientation and scale-up aspiration, the fear of failure was found to differ between national economic development and entrepreneurs. The fear of failure differ from country to country, and this is one of the important factors affecting entrepreneurial activities. It is expected that the factors influencing the growth of the start-up companies which are identified through the results of these studies, will be used to create a suitable scale-up ecosystem according to the national economic development stage.