• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.11
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• pp.1058-1063
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• 2010

The vibration analysis of a rotating cantilever beam with tip mass was studied by using DTM(differential transformation method). DTM is one of the numerical methods, for finding series solutions by transforming differential equations to algebraic ones similar with Laplace transform. The advantages of the DTM are that it is easy to understand and is effective in finding numerical solutions. Applying DTM, the natural frequencies of a rotating cantilever beam were obtained taking into consideration the effects of tip mass. Also, convergence study of DTM was performed to decide the number of terms used in eigenvalue problems. Numerical results obtained by DTM show good agreement with those by other methods. As a result, it is expected that DTM can be a useful method in vibration analysis such as that of a rotating cantilever beam with tip mass.

• Korean Journal of Computational Design and Engineering
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• v.19 no.3
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• pp.245-252
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• 2014

Engineering applications of global optimization techniques are recently abundant in the literature and it may be caused by both new methodologies arising and faster computers coming out. Many of the optimization techniques are based on natural or biological phenomena. This study put focus on enhancing the performace of Cuckoo Search (CS) among them since it has the least number of parameters to tune. The proposed enhancement can be achieved by applying surrogate-based optimization at every cycle of CS, which fortifies the exploitation capability of the original method. The enhanced algorithm has been applied several engineering design problems with constraints. The proposed method shows comparable or superior performance to the original method.

• Journal of Mechanical Science and Technology
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• v.15 no.11
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• pp.1572-1579
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• 2001

We investigate the possibility of application of the Goore Scheme to turbulence control for drag reduction. In Part I, we examine the performance of the original Goore Scheme by applying it to a si mple one-dimensional problem. For the application of the scheme to turbulence control, we extend the scheme's capability so that it can treat multi-dimensional problems and examine its validity theoretically. The convergence of the extended scheme with a dynamic memory is faster by an order of magnitude than the original scheme. In Part II, we apply the proposed scheme to reduce drag for turbulent channel flows through direct numerical simulation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.141-143
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• 2011

A Study on the Curtain Wall parts that appear to cause problems and to improve information exchange system by applying the model of SOA-based development directions are suggested. Availability of the IT industry than other industries that have closed in the field of construction such as SOA. IT systems for the compatibility of the information being sought may be applied. In the future adoption of SOA and Web service-based approach to information exchange with suppliers and improving the efficiency of information for the construction to cover the entire field of research will be conducted as a SOA system.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.127-133
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• 2007

Underfloor air distribution system is generally known to be more energy-saving and provide more comfort as compared with overhead air distribution system. In practice, however, some buildings to which underfloor air distribution system is applied have less effectiveness in saving energy and are getting dissatisfaction with cold draft caused by wind velocity of air distribution in terms of comfort. It is judged that such problems are due to failure to consider properties of underfloor air distribution system in applying it and identical design with the design standards for the existing overhead air distribution system. This study aims at introducing an air conditioning type of the occupied zone for underfloor all distribution system to see its effectiveness in saving energy for air conditioning of the occupied zone through a comparative simulation with the existing air conditioning type.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1149-1156
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• 2011

A rockbolt is one of the most important reinforcement of on-site soil, as with the shotcrete and steel rib. The rockbolt by setting within the tunnel can prevent the deformation of the ground profile; furthermore it improves the structural behavior of soil and rock. In general, the rockbolt is mainly used with reinforced steel. However, steel pipe or the materials with the same strength can be used depending on the soil conditions, ground water outflow condition, and the surrounding of applying location. In Korea, most tunnel construction sites have used cement mortar or resin for steel reinforcement on the rock. Due to the ground water outflow in the construction site, the usability of steel reinforcement is poor and it requires curing time especially after installation. To improve exist above problems, this study introduces the development of a swelled steel pipe rockbolt, as well as presents the field testing and performance results.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.1
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• pp.1-7
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• 2003

In this paper, we discuss the control scheme on active compliance control of flexible manipulators. The active compliance control scheme is extended from the scheme for rigid manipulators. To illustrate the validity of the proposed control scheme, we show experimental results for the case when the end-effector is not moving and when it is moving while applying force. Although flexible manipulators show some problems of stability yet it is clear from these results that flexible manipulators are more effective to reduce damage of environment because of link flexibility than rigid ones.

• International Journal of Knowledge Content Development & Technology
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• v.7 no.1
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• pp.5-22
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• 2017

This study discusses the library professionals' perception of the ICT Applications in engineering college libraries in Tamil Nadu. The relevant data was collected from the library professionals in the self financing engineering colleges situated in Kanchipuram and Thiruvallur district of Tamil Nadu. 625 questionnaires were distributed, 504 replied with a response rate of 80.64%. It was found that the respondents with experience 'Below 5 years'gave 'Lack of infrastructure' as the first priority. 'Lack of interest on the part of users' and 'No support from administration in training library professionals' were the second and third preferences indicated by the respondents. The least preferences were given for 'Fear of ICT application'. Similarly, respondents with experience '6-10 years' indicated 'No support from administration in training library professionals' as the first priority. The least preference was given for 'Inadequate training in ICT applications' by the above respondents. It can be inferred that the professionals accepted and need the training in ICT applications.

• International journal of advanced smart convergence
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• v.13 no.2
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• pp.44-47
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• 2024

With the advancement of Internet technology, online sales and purchases of products have become active. Along with this, the importance of user reviews is also being highlighted. Although user reviews are actively utilized for product sales and purchases, it is difficult to quickly and easily obtain useful information due to the abundance of user reviews. Therefore, prioritizing user reviews is a necessary service for customers that requires careful consideration. Metadata, which contains important information, can be effectively used to prioritize user reviews. However, it is crucial to select and use metadata appropriately according to the purpose. Lean Startup proposes a strategy of repeatedly correcting the problems of ideas or making early transitions to continue trying different approaches. In this paper, we propose a three-step method applying the Lean Startup process to analyze ways to prioritize user reviews using metadata: Build Priority, Measure Priority, Learn Priority.

• Korean Journal of Computational Design and Engineering
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• v.20 no.3
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• pp.291-297
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• 2015

A water jet cleaning robot system for micro drill bits is to refurbish micro drill bits used for the PCB manufacturing process. It can refurbish drill bits with the minimum diameter of ${\phi}0.15{\sim}0.075mm$ of which the total quantity have been discarded before. Micro drill bits with the minimum diameter of ${\phi}0.075mm$ can be cleaned by applying the water jet cleaning robot system out of the manual ultrasonic cleaning in the past for the cleaning equipment as the initial process in refurbishing. This study analyzed problems, while applying the apparatus mechanism for the workability such as the robot traces of Transfer Robot I and II, drill bit loading and unloading, and cleaning tasks in the water jet cleaning robot system in an effort to carry out simulations. In addition, the cleaning work process was optimized as the work process was verified in advance and the production quantity was analyzed through simulations.