• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.8
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• pp.718-723
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• 2007

The new concept spark plug was developed to study its influence on the combustion characteristics of SI engine. It has pre-ignition chamber in the lower end of spark plug and flame hole, in which fresh mixture gas can be introduced without any fuel supply system. This spark plug was tested with a commercial SI engine. Fuel consumption rate, emission gas and MBT timing were measured in the engine dynamometer for various flame hole numbers, hole positions, hole sizes of the pre-ignition chamber of the spark plug. And average flame propagation speed was measured by using the head gasket ionization probe in single cylinder engine. The new concept spark plug induces fast bum in combustion compared with the conventional spark plug, and MBT(Minimum advance for Best Torque) timing was retarded about $3{\sim}5^{\circ}$ crank angle. The flame hole number, hole direction and volume of pre-ignition chamber were found to influence the combustion characteristics.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.51-63
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• 2018

The study aims to articulate a definition of luxury brands, to propose a framework for consumer luxury brand relationships and to provide empirical evidence of the proposed model. The study conducted two surveys in Portugal and the United States in 2009 and 2013 for selected luxury brands. The study employs factor analysis and structural equation modelling techniques to test the hypotheses. The study finds a link between luxury products and consumer's psychological association represents in a hierarchical order of: cognitive attributes at its base level, extrinsic attributes on a secondary level and intrinsic attributes at the advance level. The findings suggest a concept for luxury brands from three dimensions of: luxury product characteristics, consumer's psychological characteristics, and consumer's psychological association with the luxury product. The research was conducted in Portugal and the United States so that there is always a potential criticism concerning the ability to generalize research results to a broader international population. The findings provide a holistic perspective in the understanding of luxury brand constructs and a definition of luxury brands in the way why consumers involve symbolic consumption. The successful application of the findings in a brand setting would be of particular interest to marketers and brand strategists.

• The Journal of Korea Robotics Society
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• v.9 no.1
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• pp.57-66
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• 2014

This paper describes the design concept of a bio-inspired legged underwater and estimating its performance by implementing simulations. Especially the leg structure of an underwater organism, diving beetles, is fully adopted to our designing to employ its efficiency for swimming. To make it possible for the robot to both walk and swim, the transformable kinematic model according to applications of the leg is proposed. To aid in the robot development and estimate swimming performance of the robot in advance, an underwater simulator has been constructed and an approximated model based on the developing robot was set up in the simulation. Furthermore, previous work that we have done, the swimming locomotion produced by a swimming patten generator based on the control parameters, is briefly mentioned in the paper and adopted to the simulation for extensive studies such as path planning and control techniques. Through the results, we established the strategy of leg joints which make the robot swim in the three dimensional space to reach effective controls.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.63-72
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• 2014

Pyroprocess technology has been considered as a fuel cycle option to solve the spent fuel accumulation problems in Korea. The Korea Atomic Energy Research Institute has been studying pyroprocess technology, and the conceptual design of an engineering-scale pyroprocess facility, called the Advanced Fuel Cycle (AFC) facility, has been performed on the basis of a 10tHM throughput per year. In this paper, the concept of the AFC facility was introduced, and its safety evaluations were performed. For the safety evaluations, anticipated accident events were selected, and environmental safety analyses were conducted for the safety of the public and workers. In addition, basic radiation shielding safety analyses and criticality safety analyses were conducted. These preliminary safety studies will be used to specify the concept of safety systems for pyroprocess facilities, and to establish safety design policies and advance more definite safety designs.

• Journal of Korean Society for Quality Management
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• v.49 no.4
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• pp.467-482
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• 2021

Purpose: The main theme of this study is to determine the optimal control limit of conditional variance investigation by mathematical approach. According to the determination approach of control limit presented in this study, it is possible with only one parameter to calculate the control limit necessary for budgeting control system or standard costing system, in which the limit could not be set in advance, that's why it has the advantage of high practical application. Methods: This study followed the analytical methodology in terms of the decision model of information economics, Bayesian probability theory and Taguchi's quality loss function concept. Results: The function suggested by this study is as follows; ${\delta}{\leq}\frac{3}{2}(k+1)+\frac{2}{\frac{3}{2}(k+1)+\sqrt{\{\frac{3}{2}(k+1)\}^2}+4$ Conclusion: The results of this study will be able to contribute not only in practice of variance investigation requiring in the standard costing and budgeting system, but also in all fields dealing with variance investigation differences, for example, intangible services quality control that are difficult to specify tolerances (control limit) unlike tangible product, and internal information system audits where materiality standards cannot be specified unlike external accounting audits.

• Journal of The Korean Association of Information Education
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• v.6 no.3
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• pp.288-297
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• 2002

The paradigm of education has changed with the progress of the information and communication technology. In school, there has been developing and animately discussing many data and ways of using web-practicality for teaching and learning. On the other hand, relatively, there are negligent faces about web-practicality for extension of emotion and will of our children. The common points of pre-studies about the increase of self-concept show that it is difficult to join all of the information because the work is off-line, therefore limiting it's advance so that the program is improved. This study has designed and embodied the system of web based self-expression training program. The result of application of this system has showed the positive effect on formation of self-concept of Cheongju elementary school students.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.40-45
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• 2001

Arbitration is adopted recently as dispute resolution vehicle for major construction projects in Korea. These arbitration cases show that complex construction disputes are resolved reasonably by newly-introduced arbitration process and this trend will continue. This paper reviews the expanded concept of dispute resolution for the new approaches to the disputes resolution processes in construction projects. The expanded concept includes that disputes need to be assessed reactively and proactively in construction project and need to be managed effectively in advance. In this paper, dispute resolution methods used in Korea are reviewed and analyzed against ADR methods available in US construction industry The new approaches to the dispute resolution Processes are based on the concept of 'Disputability' which means dispute management through prevention, avoidance and predictability of dispute issues and characteristics.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.305-313
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• 2020

The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

• Journal of Ship and Ocean Technology
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• v.5 no.2
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• pp.1-13
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• 2001

Data in one Product Model for shipbuilding is inevitably referenced and manipulated during each phase of design or production activities, and data or manipulation status naturally varies from the original with the advance of each activities. For Object-Oriented approach, it is hard to identify classes dealing with those variations, and even if once a product model is developed, it might be getting much harder to modify it to cope with a new additional phase of activities. This paper proposes an Instance-Oriented Modeling Method, temporarily named “Concept-Relationship Modeling Approach”, which handles Data structure and Behavior independently of each other in order to resolve the difficulties above.

• Journal of the Korea Safety Management & Science
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• v.6 no.1
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• pp.71-79
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• 2004

According to the changing environment of management, the concept of the one-to-one marketing is appeared in the environment of management by high Quality that customers needs. In this paradigm, CRM(Customer Relationship Management) offering integrated multiple view points is able to be executed by the advance of Information Technology (IT). In this study, the environment and the management status of the steel company that CRM implemented is analyzed. This study presents the system architecture which applies OLAP(on-line analytical processing), web technologies, and logistics service. Then this research presents a variety of effects and development direction in the future.