• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.5
• /
• pp.54-59
• /
• 2012

This study dealt with effect of the grinding in SCM420H planetary gears. The hardness, tooth profile, lead and roughness of the gear surface can be improved by grinding process. Therein, the grinding techniques are widely used especially as one of the physical surface improvement methods. As the results, the gear grinding process reduced vibration and noise, and increased the life of the gear. And the gear grinding improved the surface of gear tooth in a short time and low cost, thus, it is a very important process in manufacturing industry. But nowadays, it is hard to find the detail information of gear grinding process. The test piece is a planetary gear which is used in the industrial machine. The manufacture process of the test piece contains hobbing, shaving, carburizing and grinding. This study investigated the effect of the grinding process to the physiognomy and the fatigue strength of test piece which was made by SCM420H.

• Industrial Engineering and Management Systems
• /
• v.9 no.3
• /
• pp.215-226
• /
• 2010

Since product design strongly depends on the experience and ability of the designers, and a long lead time is required for the product design stage, introducing a support system related to this experience and ability is an effective technique to reduce the lead time. In this paper, an information system is developed to support the development of engineering mechanisms with the evaluation of the assembly process on the basis of the abstract functions required for new products. The developed system is based on a database system involving the following data structure: (1) a hierarchical structure related to information about the product functions, (2) the relationship between the parts and engineering functions and/or mechanisms of products, and (3) the relationship between the parts and manufacturing characteristics. The system stores the relationships between the product functions, structure of parts, and assembly characteristics. This information can then be interactively retrieved using the data structure described in (1), (2), and (3). A procedure for designing new products is proposed that involves using the information about existing products. This paper presents the characteristics of the proposed procedure and the developed information system. In addition, a case study of the redesign of a simple structured robot by using the proposed procedure is discussed.

• Journal of Industrial Convergence
• /
• v.21 no.3
• /
• pp.57-64
• /
• 2023

As the technology advances and convergence progresses, companies are increasingly interested in the appropriability mechanism. Therefore in this study tried to understand the effectiveness of the appropriability mechanism of domestic IT companies. To this end, 7 appropriability mechanisms were finally derived and empirically analyzed from a review of previous studies and experts. As a result of the analysis, the importance of lead time advantage, patent, secrecy, complementary sales and service, design registered, complementary manufacturing, and learning curve effect was shown in the order of SW companies. HW companies, the importance of patent, secrecy, lead time advantage, design registered, complementary sales and service, learning curve effect, and complementary manufacturing were shown in the order of importance. Also patent, secrecy, and lead time advantage was selected as important factors. The results of in this study are expected to be used as useful guidelines on establishing an appropriability mechanism strategy in companies.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.24 no.5
• /
• pp.489-495
• /
• 2015

Forging is a manufacturing process involving the shaping of metal using localized compressive forces and the process of deforming metal into a predetermined shape using certain tools and press according to the temperature. Forging provides stronger metal parts than that possible by casting or machining. Conventional clutch jaw parts have been developed through cold forging and precision machining; however, fabrication of integral clutch jaw parts for farm machinery has not been reported yet. These parts were developed by applying a complex forging technology combining cold and hot forging. The integrated forming technology proposed in this study will be useful for reducing the lead-time for manufacturing, improving the accuracy of products, and eliminating the welding process.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10b
• /
• pp.1250-1255
• /
• 1990

This paper discusses an optimal cyclic scheduling problem for a FMC (Flexible Manufacturing Cell) modeled by a two-machine flowshop with two machining centers with APC's (Automated Pallet Changers), an AGV (Automated Guided Vehicle) and loading and unloading stations. Cyclic production in which similar patterns of production is repeated can significantly reduce the production lead-time and WIP (Work-In-Process) in such flexible, automated system. Thus we want to find an optimal cyclic schedule that minimizes the cycle time in each cycle. However, the existence of APC's as buffer storage for WIP makes the problem intractable (i.e., NP-complete). We propose an practical approximation algorithm that minimizes, instead of each cycle time, its upper bound. Performances of this algorithm are validated by the way of computer simulations.

• Journal of Information Processing Systems
• /
• v.15 no.1
• /
• pp.181-188
• /
• 2019

A production system is a management system that supports all activities to perform production operations at the manufacturing site. From the point-of-view of a smart factory, smart manufacturing systems redesigned the concept of onsite production systems to fit the entire system and its necessary functional composition. In this study, we select the key functions needed to build a smart factory for a PCB line and propose a new six-step model for the deployment of a smart manufacturing system by integrating essential functions. The smart manufacturing system newly classified the production and operation tasks of PCB manufacturing and selected necessary functions through requirement analysis and benchmarking of advanced companies. The selected production operation tasks are mapped to the functions of the system and configured into seven modules, and the optimal deployment model is presented to allow flexible responses to the characteristics of the tasks. These methodologies are first presented in this study, and the proposed model was applied to the PCB line to confirm that they had significant changes in the work method, qualitative effects, and quantitative effects. Typically, lead time and WIP have reduced by about 50%.

• The Journal of Information Systems
• /
• v.17 no.4
• /
• pp.301-319
• /
• 2008

The display market has been replaced by the FPD (Flat Panel Display) from the CRT (Cathode-Ray Tube) since the late 1990s. In the FPD production line, the most equipment has high price. Thus, when the equipment has multi-function, the repetitive process is arranged for the equipment. However, such disposition of equipment results in more complicated process flow owing to repetitive operations. This reduces the production capacity and increases lead-time in turn. In this paper, we develop an AutoMod simulation system that derives to information about the quantity, production lead-time, utilities of facilities, and occupation rates of racks. In this simulation system, we consider the situation where the equipment might be broken and suspended randomly. For the developed system, we first evaluate a production plan with current layout and then, propose a revised alternative plan. Using the same simulation scheme, we investigate comparing the production quantity and lead-time with the two plans. In addition, for a proposed alternative, we try to forecast the most adequate rule between the two job dispatching rules which are FOR (Fewest Operation Remaining) and FCFS (First Come First Serve) through simulation.

• Journal of the Society of Naval Architects of Korea
• /
• v.53 no.1
• /
• pp.29-36
• /
• 2016

In shipbuilding and offshore plant construction, pipe-stools of various types are installed. Moreover, these are many quantities but they must be installed in a successive manner. Due to these characteristics the pipe-stool installation processes easily tends to cause the schedule delays in the overall production processes. In order to reduce delay, the goal of this study is to predicts production’s lead time before manufacturing. Through this predictions it’s expected to reduce total production’s lead time by improving it's process. First of all, we made MLR(Multiple Linear Regression) and PLSR(Partial Least Square Regression) model to predict pipe-spool's lead time and then compared predictability of MLR and PLSR model. If a explanatory variable is added, it will be possible to predict results precisely.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2987-2997
• /
• 2011

As a public transit playing an important role in the era of high gas prices, subway corresponds the national strategy 'Low carbon, Green growth'; accordingly, passengers who would use the transportation are steadily increasing. Subway operators are required to provide subway users with services based on higher-quality system, safety, convenience & high reliability level. Furthermore, as the legally allowed maximum life time of EMUs is extended, it is necessary to localize & standardize the parts of EMUs. This paper presents a modelling of systematic EMU(SR001) manufacturing technique which enables us to reflect passenger and subway operator's demands in the whole EMU manufacturing process from the initial design phase to its completion by making full use of the know-how based on subway operators' experiences. SR001 enabled SMRT's staffs to participate in the EMU design & its equipment manufacturing; consequently, it realized the innovative system which meets passengers' requirements. Moreover, the process lead time was reduced dramatically. The result of this research will be helpful in providing useful guidelines for railway industry policy and development making in Korea.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.30 no.4
• /
• pp.141-154
• /
• 2007

Nowadays, customer-oriented manufacturing enterprises such as airplane, ship, ship engine, etc are knowledge-intensive and higher added value industries. In these companies, to quickly respond customer's order, a quotation management is a very important task. But, this task is very complex, time-consuming, resource- consuming, and difficult process because it is related with many departments within a company. In this paper, for the effective and efficient quotation management, the concept of product specification framework is introduced because a quotation BOM (bills of material) can be created from product specification. Also, this paper presents the product specification framework based quotation management process and implements the quotation management system for the ship engine division of 'H' company, one of customer-oriented manufacturing enterprises. As a result, the proposed quotation management concept reduced a lead time of drawing out quotations from $3{\sim}10$ days to 1 hour. And, the constructed quotation management system achieved a rapidity, accuracy, quality, and workload reduction of the quotation management process.