• Journal of Institute of Control, Robotics and Systems
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• v.11 no.4
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• pp.344-352
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• 2005

The modem production systems are required to produce many items. This is due to the fact that society has become more complex and the customers' demands have become more varied. The demand for complex production systems of various purposes, which can flexibly change the content of work, has increased. One of such production systems is FMS (Flexible Manufacturing System). Limited resources must be used in FMS when a number of working procedures are simultaneously being undertaken because the conditions of stand-by job processes cannot be changed. Researchers are currently being conducted to determine ways of preventing deadlocks. In this study, we proposes the algorithm for detection and recovery of a deadlock status using the DDAPN(Deadlock Detection Avoidance Petri Net). Also, we apply the proposed algorithm has a feature to the FMS.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.860-863
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• 1994

Main sources of increased vibrations and air noise on ship are main and auxiliary engines and ship ducts. The various ways of transfer of vibration energy and air noise in passenger cabin of a vessel require, in general case, of various methods of attenuation. The transfer of vibration energy from engines through a support requires, alongside with shock-absorbers, availability active shock-absorbers. The transfer of vibration energy and hydrodynamic noise on ship ducts requires availability, alongside with flexible muffler, active mufflers. The availability of air noise from working equipment can require, along with absorbent covers, of space systems of active noise control. In the given article it is spoken about the unified approach to formation of the block-diagram of active noise and vibration control. The complex approach permits to receive additional efficiency in reduction of noise in passenger cabin of vessels.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.33
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• pp.247-275
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• 2007

This paper is to propose the Direction for the institutional improvement of Financial Supply Chain Management(FSCM) Solution which are currently coming into operation under Global e-Trading Platform. The Financial Supply Chain compromise the entire trade processes and information that manage a trader's cash, Accounts payable and receivable, Risk, working capital, and so on in international trade transaction. From a buyer's perspective, this involves the full procurement-to-payment process. For the seller, it is the order-to-cash cycle. Bolero provides the party concerned a e-trade platform which conformed to these fundamental pre-requisites to underpin fully electronic trade. But this FSCM solution have failed to provide the efficient platform to effectively manage the process of Global e-Trade because it does not correspond with e-Trade environment. Therefore, present FSCM system need the institutional improvement as follows: AA) Strengthening the role of the correspondent Bank under e-Trade System, BB) Extending the function of e-Trade intermediary institution, CC) The introduction of Trade Insurance System, etc. So, by streamlining and automating these processes on an open and flexible platform, The party concerned can optimize their trade transaction and maintain better relations with their business partners

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.7
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• pp.677-682
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• 2007

Concurrent competition for finite resources by multiple parts in flexible manufacturing systems(FMS's) and inappropriate initial marking or net structure of Petri net with share resources results in deadlock. This is an important issue to be addressed in the operation of the systems. Deadlock is a system state so that some working processes can never be finished. Deadlock situation is due to a wrong resource allocation policy. In fact, behind a deadlock problem there is a circular wait situation for a set of resources. Deadlock can disable an entire system and make automated operation impossible. Particularly, an unmanned system cannot recover from such a status and a set of jobs waits indefinitely for never-to-be-released resources. In this paper, we proposed a deadlock prevention method using siphon and trap of Petri net. It is based on potential deadlock which are siphon that eventually became empty. This method prevents the deadlock by the control of transition fire and initial marking in the Petri net. An given example of FMS is shown to illustrate our results with deadlock-free.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.2
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• pp.112-117
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• 2016

In the construction industry, concrete polishing is used to grind and rub the surface of concrete grounds with polishing machines to increase the strength of the concrete after deposition. Polishing is performed manually in spite of the generation of dust and the requirement of frequent replacements of the polishing pad. The concrete polishing robot developed in this research is a novel polishing automation system for preventing the workers from being exposed to poor working environments. This robot is able to change multiple polishing tools automatically; however, the workers can conveniently replace the worn-out polishing pads with new ones. The mobile platform of the polishing robot employs omnidirectional wheels to enable a flexible motion even in small and complicated workspaces. To evaluate the performance of the developed concrete polishing robot, extensive experiments including square trajectory tracking, automatic tool changing, actual polishing, and path generation simulation were performed.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.567-573
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• 2003

Korean High Speed Train (KHST) has been tested on high speed line in JungBu site since it was developed in 2002. The data acquisition system was developed to accomplish successfully this on-line test for proving the dynamic Performance of KHST. This system was consist of the personal computers based on National Instrument PXI modules and the test programs based on Labview 6i. This paper shows that this system is efficient to acquire the test data through the multi-channels connected the accelerometers which located in long distance places and flexible to change and add channels for data acquisition. The dynamic analysis of an on-line test is very complicate because the environmental conditions, as examples radius of curve, inclination of the track, tunnels, bridges, and so forth, and running conditions, as examples driving, braking, the number of working motors, and so forth, have an effect on the results. Therefor, the analysis method is important and this paper proposes the efficient procedure graphically, showing the proposed method simplify the accelerations of 5th bogie frame acquired during the on-line test for KHST.

• Archives of design research
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• v.11 no.2
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• pp.17-28
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• 1998

With the renewed definition of "office". it's function and role has been reduced. Therefore. home oofices are beginning to draw people's attention. Office within the home is called SOHO (Small Office Home Office). SOHO has become possible with the development of information and telecommunication network technology. Recently. companies are adopting the SOHO system along with the trends of business restructuring. The SOHO offers workers to enjoy more flexible work time and enhance concentration thus improving jop efficiency. Companies will be able to cut down on fixed expenses and increase productivity. In addition. such working conditions will contribute to relieve traffic and environmental problems and furthermore it will make it possible to take advantage of potential workforce of women. the elderly and the handicapped. "Home Office" is expected to be one of the prevailing work system in the near future. Therefore. it is all the more important to study design problems including space design and furniture arrangement in order to improve work efficiency and provide a creative working environment. Moreover. architects and interior designers as well as experts on related fields such as information network. telecommunications. management and employment should continue to carry out joint researches for reasonable home office furniture and environment design.nd environment design.

• Journal of Families and Better Life
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• v.28 no.2
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• pp.63-76
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• 2010

A law facilitating a family-friendly social environment was legislated in December 2007. According to the law, projects for facilitating a family-friendly social environment consisted of a family-friendly working environment, a community environment, and the promotion of a family-friendly culture. There has been much progress in developing a family-friendly working environment through projects such as those advocating for flexible work hours, an employee support system, and child care and a family care support system. However, in terms of a family-friendly community environment project, there was no noticeable advancement. Hence, this study was conducted to find ways to vitalize the family-friendly village project in terms of the family-friendly community environment project. The major findings of this study were as follows: A family-friendly village could be structured on the three axes of time, space, and relation. The model of the family-friendly village project consists of the following three steps: motivation, systematization, and participating & practicing. In the motivation step, integration, community, and sustainability were needed as basic ideologies for a family-friendly village. In the systematization step, providing systematic educational systems for residents taking on leadership and activist roles was stressed. In the participating & practicing step, many ways to facilitate residents' social relationships were suggested: starting the project from matters of common interests, making the resolution of families' problems a communal task of the residents, accepting the opinions of various groups associated with the matter, and taking a differentiated project process according to the geographic, socio-economic, and demographic characteristics of the groups. It is strongly suggested that the family-friendly village should be taken as a common functional scheme in everyone of eight livable village models because a key factor in a family-friendly village, family care, serves an essential function in any livable village model.

• Proceeding of KASS Symposium
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• 2005.05a
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• pp.116-124
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• 2005

The recent large-spatial structures are frequently made from light-weight structural system and it has a good mechanical efficiency and uses new materials. The large space is made by light-weight structural system using tension members mainly, and generally it is called a soft structure. The cable dome structures which are a soft structures are very flexible, the stresses and nodal coordinates of other members are changed when we control the stress of one member. Therefore, we have to do two kind of works for effective and accurate construction of the cable dome structures. The first work is making a working scenario to complete the final objective form and the second is revising constructional errors occurred in process of the actual works. These works are called constructional analysis. At this time, we have to consider geometric nonlinearity to reflect the sensitivity by the initial stresses of cable dome structures, and constructional analysis comes down to a nonlinear problem after all. In this study, we try to approach the constructional analysis of the cable dome structures using the numerical method, and then verify it.

• Journal of Biosystems Engineering
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• v.31 no.5 s.118
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• pp.430-435
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• 2006

Greenhouse horticulture in South Korea covered about 52,000 ha in 2005. Greenhouse area of about 12,000 ha has been heated during winter season with heating cost of $20{\sim}40%$ of total Production cost. Farmers engaged in greenhouse horticulture were changed into aged people. Therefore the laborsaving of working process and the saving of greenhouse heating cost should be accomplished simultaneously to increase income of greenhouse horticulture. The best method for saving of greenhouse heating cost is to install thermal tunnels into greenhouse. Then hot air heaters using fossil fuel should be changed into hot water heaters. In other words air heating using forced convection should be changed into natural convection system. In this research coil tube made of flexible PE pipe was designed as hot water heat exchanger and its heat exchanging characteristics were analyzed. This new heat exchanger has been adopted as a natural convection system for hot water heating of greenhouse horticulture.