• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.113-124
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• 2008

Distributed operation of overall structural design process, by which product optimization and process parallelization are simultaneously implemented, is presented in this paper. The database-interacted hybrid method, which selectively takes the accustomed procedure of the conventional method in the framework of the optimal design, is utilized here. The staged application of design constraints reduces the computational burden for large complex optimization problems. Two kinds of numeric and graphic processes are simultaneously implemented by concurrent engineering approach in the distributed environment of PC networks. The former is based on finite element optimization method and the latter is represented by AutoCAD using AutoLISP programming language. Numerical computation and database interaction on servers and graphic works on independent clients are communicated through message passing. The numerical experiments for some steel truss models show the validity and usability of the method. This study has sufficient adaptability and expandability, in that it is based on general methodologies and industry standard platforms.

• Journal of Information Technology Application
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• v.2 no.1
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• pp.139-160
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• 2000

This paper suggests a technique for evaluating cognitive process when a working group performs its group tasks. First, it review a theory of distributed cognition which provides a theoretical background for investigating group's cognitive process. Then, it presents a procedure for DGOMS(Distributed GOMS) evaluation which is an extension from GOMS. GOMS is an analytica evalutation technique that has been used at the individual level. DGOMS analyzes task completion time and compares workload among group members on the basis of each member's task execution time, communication time, and cognitive workload. DGOMS can be applied to a situation where a group of people are working together for a common goal using a technical subsystem such as information systems.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.621-631
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• 2017

In this paper, we study the various impacts of connecting distributed generation (DG) to the distribution network. The comprehensive evaluation index system (CEIS) of four hierarchies is established, considering economy, reliability and voltage quality, and the calculation methods of different indexes are presented. This paper puts forward an improved triangular fuzzy number analytic hierarchy process (ITFNAHP) to weight the second level indexes (SLI) and the third level indexes (TLI), and calculates the variation coefficient to weight the fourth level indexes (FLI). We calculate the comprehensive weight coefficients based on the weight coefficients of the SLI, TLI and FLI, and then calculate the comprehensive evaluation of satisfaction (CES) of different access schemes. On the basis of the IEEE 33-bus example system, simulations of the calculation methods and the comprehensive evaluation method are carried out under different DG access schemes according to the same total investment cost and the same permeability, respectively, and the simulation results are analyzed and discussed.

• Particle and aerosol research
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• v.6 no.2
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• pp.61-67
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• 2010

In this paper, we describe a new method to form polymer thin films, in which carbon nanotubes (CNTs) are homogeneously distributed so that they can strengthen the mechanical property of resulting polymer film. To do so, we first homogeneously mixed CNTs with polymer in a DMF solvent. With the assistance of ultrasonic nebulizer, the polymer/CNT solution was then aerosolized into micro-sized droplets and finally turned into solidified polymer/CNT composite particles by gas-phase drying process. As the results of SEM and TEM analysis, CNTs were found to be homogeneously immobilized in the polymer matrix particles due to rapid drying process in the gas phase. For comparison purpose, (i) the polymer/CNTs composite particles prepared by aerosol processing method and (ii) polymer/CNTs sheets prepared by simple solution-evaporation method were employed to form polymer/CNTs composite thin films using a hot press. As the result, the aerosol processing of composite particles was found to be a much more effective method to form homogeneously distributed-CNTs in the polymer matrix thin film.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.2
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• pp.255-269
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• 2008

The increasing dynamic and distributed nature of a business and manufacturing environment makes it hard to collaborate between design and manufacturing parties. The seamless collaboration necessitates a manufacturing quote service (MQS) that delivers manufacturing quotes timely for designer's requests. After envisioning a SOA-inherited collaboration framework, the paper details MQS' functionalities, and syntax and semantics of collaboration messages (i.e., RFQ and manufacturing quote). The MQS is implemented as a Web Service so as to be accessible by designers. For each RFQ, the MQS adaptively generates a responding manufacturing quote by using the DPM library and real-time shop status information. The paper also presents an evolution process that shows the whole process of RQF generation from given product design data. The proposed framework enabled partners to exchange engineering data rapidly and adaptively during the dynamic collaboration, and also increased the benefits of distributed and global production.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.257-262
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• 2001

As computer-related technologies have been developed, legacy design systems have not been appropriate for new computing environment. Therefore, it is necessary that most of them are either modified or newly developed. However, this requires quite much amount of cost and time. This paper presents a method of extending legacy design system without modification using XML and XSLT. In order to apply the developed method, a good example of legacy design systems, AGMA gear rating system has been extended so as to be suitable for the distributed computing environment. An XML document for AGMA gear rating process is defined. It is transformed to the form of the input document of AGMA gear rating system by XSLT processor according to the transformation rules defined in the AGMA gear rating XSLT document. After that, AGMA gear rating system reads this input document and generates an output document in the server. These operations are automatically executed by the external legacy system controller without user interactions. Using these operations, AGMA gear rating web service has been developed based on SOAP and WSDL to provide the functions of legacy AGMA gear rating system through the distributed network. Any system or user can implement AGMA gear rating process independently to the platform type, without making it for oneself, by simply referring the AGMA gear rating web service via Internet.

• Journal of the Korean Professional Engineers Association
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• v.21 no.4
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• pp.19-32
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• 1988

Whereas is non-symmetrical distribution manufacturing process the traditional X-chart by Shewhart is not plotted relatively on the central line but plotted on the skew of upper-hand side or lower-hand side. That is to say, for the purpose of producing either upper-specification-oriented items or lower-specification-oriented items, and when we carry out tighter control so as to have them pass only its specifications, the distribution shape naturally has a non-normal distribution. In the Shewhart X-chart, which is the most widely used one in Korea, such skewed distributions make tile plots to be inclined below or above the central line or outside the control limits although no assignable causes can be found. To overcome such short comings is non-normally distributed processes, a distribution-free type of confidence interval can be used, which should be haled on order statistics. This thesis is concerned with the design of control chart based on a sample median which is easy to use in practical situation and therefore properties for non-normal distributions, such as Gamma, Beta, Lognormal, Weibull, Pareto, and Truncated-normal distributions, may be easily analyzed. To enhance this improvement, I proved the property of practical applications of control chart method by comparing and analyzing the case studies of practical application of special purpose control chart method, and also by introducing the new designed median control chart.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.6 no.3
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• pp.264-269
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• 2006

This paper presents the strategy for searching a hidden object in an unknown area for using by multiple distributed autonomous robotic systems (DARS). To search the target in Markovian space, DARS should recognize th ε ir surrounding at where they are located and generate some rules to act upon by themselves. First of all, DARS obtain 6-distances from itself to environment by infrared sensor which are hexagonally allocated around itself. Second, it calculates 6-areas with those distances then take an action, i.e., turn and move toward where the widest space will be guaranteed. After the action is taken, the value of Q will be updated by relative formula at the state. We set up an experimental environment with five small mobile robots, obstacles, and a target object, and tried to research for a target object while navigating in a un known hallway where some obstacles were placed. In the end of this paper, we present the results of three algorithms - a random search, an area-based action making process to determine the next action of the robot and hexagon-based Q-learning to enhance the area-based action making process.

• Geomechanics and Engineering
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• v.5 no.3
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• pp.241-261
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• 2013

The bearing mechanism of pile during installation and loading process which controls the deformation and distribution of strain and stress in the soil surrounding pile tip is complex and full of much uncertainty. It is pointed out that particle crushing occurs in significant stress concentrated region such as the area surrounding pile tip. The solution to this problem requires the understanding and modeling of the mechanical behavior of granular soil under high pressures. This study aims to investigate the sand behavior around pile tip considering the characteristics of sand crushing. The numerical analysis of model pile loading test under different surcharge pressure with constitutive model for sand crushing is presented. This constitutive model is capable of predicting the dilatancy of soil from negative to positive under low confining pressure and only negative dilatancy under high confining pressure. The predicted relationships between the normalized bearing stress and normalized displacement are agreeable with the experimental results during the entire loading process. It is estimated from numerical results that the vertical stress beneath pile tip is up to 20 MPa which is large enough to cause sand to be crushed. The predicted distribution area of volumetric strain represents that the distributed area shaped wedge for volumetric contraction is beneath pile tip and distributed area for volumetric expansion is near the pile shaft. It is demonstrated that the finite element formulation incorporating a constitutive model for sand with crushing is capable of producing reasonable results for the pile loading problem.

• Journal of Distribution Science
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• v.18 no.11
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• pp.47-59
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• 2020

Purpose: The purpose of this study is to investigate the distribution of ancient Korean books around the world, and to study the process and impact of Myongsimbogam's distribution to East Asia and Europe. Research design, data and methodology: This study conducted literature research as its research method. The scope of research covers Korea, China, Japan, Vietnam, Spain, Germany and Russia. Results: Ancient Korean books were distributed through the Kwanpan and Banggakbon, and leaked overseas in historical circumstances. Myongsimbogam was distributed to Korea, China, Japan, Vietnam, Spain, France, Germany, and Russia. Myongsimbogam was the first ancient book to be translated into Western languages. Conclusions: The distribution of Myongsimbogam promoted the exchange of spiritual civilizations in the East and West, and became the basis for maintaining an individual philosophy, as well as social order. Therefore, the distribution of Myongsimbogam needs to be further expanded. For this, it is necessary to translate Myongsimbogam into English and popularize it through e-books, audio books and various lectures. While previous studies on Myongsimbogam have mainly focused on personality and moral education, this study is significant in that it examines the distribution and dissemination process of Myongsimbogam, its influence and significance.