• International Journal of Precision Engineering and Manufacturing
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• 제5권2호
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• pp.60-67
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• 2004

For improving the motion accuracy of hydrostatic tables, a corrective machining algorithm is proposed in this paper. The algorithm consists of three main processes. The reverse analysis is performed firstly to estimate the rail profile from the measured linear and angular motion error, in the algorithm. For the next step, the corrective machining information is obtained based upon the estimated rail pronto. Finally, the motion errors on the correctively machined rail are analyzed by using the motion error analysis method. These processes are iterated until the analyzed motion errors are satisfactory within the target accuracy. In order to verify the validity of the algorithm theoretically, the motion errors calculated by the estimated rail after the corrective machining process, are compared with those by the true rail which is previously assumed as the initially measured value. The motion errors calculated using the estimated rail show good agreement with the assumed values, and it is shown that the algorithm is effective in acquiring the corrective machining information to improve the accuracy of hydrostatic tables.

• International Journal of Precision Engineering and Manufacturing
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• 제5권3호
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• pp.62-68
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• 2004

Effectiveness of a corrective machining algorithm, which can construct the proper machining information to improve motion errors utilizing measured motion errors, is verified experimentally in this paper, Corrective machining process is practically applied to single and double side hydrostatic bearing tables. Lapping process is applied as a machining method. The machining information is obtained from the measured motion errors by applying the algorithm, without any information on the rail profile. In the case of the single-side table, after 3 times of corrective remachining, linear and angular motion errors are improved up to 0.13 $\mu\textrm{m}$ and 1.40 arcsec from initial error of 1.04 $\mu\textrm{m}$ and 22.71 arcsec, respectively. In the case of the double-side table, linear and angular motion error are improved up to 0.07 /$\mu\textrm{m}$ and 1.42 arcsec from the initial error of 0.32 $\mu\textrm{m}$ and 4.14 arcsec. The practical machining process is performed by an unskilled person after he received a preliminary training in machining. Experimental results show that the corrective machining algorithm is very effective and easy to use to improve the accuracy of hydrostatic tables.

• Journal of Mechanical Science and Technology
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• 제17권6호
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• pp.896-905
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• 2003

A linear motor has many advantages next to conventional feed mechanisms: high transitional speed and acceleration, high control performance, and good positioning accuracy at high speed. Through the omission of a power transfer element, the linear motor shows no wear and no backlash, has a long lifetime, and is easy to assemble. A disadvantage of the linear motor is low efficiency and resultant high-temperature rise in itself and neighboring structures during operation. This paper presents the thermal behavior of the linear motor as a feed mechanism in machine tools. To improve the thermal behavior, an insulation layer is used. By placing the insulation layer between the primary part and the machine table, both the temperature difference and the temperature fluctuation in the machine table due to a varying motor load are reduced.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.635-640
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• 2000

Thermal deformation of machine tools can be evaluated from the analysis of the whole temperature field. However, it is extremely inefficient and impossible to acquire the whole temperature field by measuring temperatures of every point. So, a temperature estimator, which can estimate the whole temperature field from the temperatures of just a few points, is required. In this paper, 1-dimensional heat transfer problem is modeled with modal analysis and state space equations. and then state observer is designed to estimate the intensity of heat source and the whole temperature field in real-time. The reliability of this estimator is verified by making a comparison between solutions by the proposed method and the exact solutions of examples. The proposed method is applied to the estimation of temperature distribution in a ball screw system.

• 한국환경복원기술학회지
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• 제22권1호
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• pp.13-31
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• 2019

Green spaces are recognised for the benefits. They bring to the quality of people's lives. However, since the 1980s there has been a general increase in poorly-managed green spaces. In an attempt to address this issue, green space policy has changed its focus on green space management through the gradual introduction of green space evaluation tools, such as the Green Flag Award (GFA). The GFA, as an established green space evaluation tool in the UK, reflects a shift in policy drivers of green spaces management. However, there is a lack of research investigating the contextualisation between a wide range of policy contexts and such green space evaluation tools (the GFA in this study). The aims of this study are therefore to explore the development of green space evaluation since the late 1990s, with respect to the growth of the GFA and its impact on other evaluation tools across the UK and several countries. To address the aims, this study employs in-depth literature reviews on UK green space policy mainly conducted by government. In addition, case studies are presented, focusing on the GFA and independent green space evaluation tools intrinsically derived from the GFA in the UK's cities and Nordic countries. Results show that based on the awareness of the severity of declining standards of green spaces, newly emerging policy arrangements have been adopted to address negative issues, which affect the standard of green spaces such as the transfer of responsibility for green space management, the implementation of Compulsory Competitive Tendering and ongoing budget cuts. Significantly, the GFA's indicators reflect the emerging changes of economic and social contexts associated with green spaces management where, in particular, the prospect of continuous budget cuts, which encourages communities to become involved in green space management. The GFA has widely contributed to leading such UK's cities and other countries to be able to create their independent green space evaluation tools in different approaches based on stakeholders' (mainly community) involvement in the decision-making process of green space evaluation. In conclusion, this study implies that successful green space evaluation tools do embody the value of green spaces and address drivers of emerging green space management with correspondence to the context of policy arrangements. Importantly, stakeholders have an opportunity to be involved in a partnership in the decision-making process through some green space evaluation tools. It is hoped that for well-managed green spaces this study will contribute valuable knowledge to our existing understanding of green space management in an era of austerity.

• 지식경영연구
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• 제10권3호
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• pp.51-80
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• 2009

The purpose of this study is to empirically analyze the impact that occurs when Korean organizations make practical use of various information technology tools and systems in the knowledge management process, such as sharing, learning and creating knowledge. Such a process is usually made through online and offline knowledge management activities. This paper also verifies how the externalization of tacit knowledge, and the internalization of explicit knowledge via the Internet and offline socialization activities have altered the mechanisms of knowledge transfers inside organizations. For the research, a survey was conducted on the satisfaction and usability levels of information technology, and the impact of IT usage on the results of knowledge management activities and knowledge transfers. 622 Korean organizations were surveyed, including major listed firms and public organizations. The results were examined as an online/offline integration process using SECI's Model proposed by Nonaka (1994, 1995). The analysis shows that information technology satisfaction and the usage of information technology help accelerate the pace of the knowledge flow and amplify the volume of the knowledge transfer by boosting the externalization and internalization processes-also known as knowledge management activities. However. there is no distinct correlation between information technology and socialization, an offline knowledge transferal activity. In particular, the quality of knowledge-an end result of knowledge transfer-does not improve merely by the externalization of online knowledge and instead requires the internalization of knowledge processes. Above all, the research reveals that offline socialization processes vastly contribute to the improvement of knowledge quality. This paper suggests that in order to ensure a transfer of quality knowledge, an organization or a company should focus on the use of information technology rather than the satisfaction level of information technology, and that knowledge transfers via the Internet has limitations in creating high quality of knowledge. For an organization to ensure the transfer of high-quality knowledge, the organization should not entirely hinge the transfer of knowledge online, as it is essential to have an offline method-a form of socialization such as a 'community of practice.'

• 무역상무연구
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• 제60권
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• pp.27-46
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• 2013

The Incoterms and United Nations Convention on Contract for the international Sales of Goods(CISG) allocate a risk in their articles. These rules make a decision that the parties who make a transaction are bound to bear the risk or damages of goods. Though a goods have a damages or loss during a transportation, buyer is liable for the payment of purchase price. In this case, this paper defines the meaning whether who can bear the risk under Incoterms and CISG. In the majority cases which deal between parties, after shipment or at the end of carriage, the loss or damages are found in buyer's hand. If a damages or loss is made during transit, customarily these risk are covered by insurance. Otherwise, these rules provide a tools for solving this problems. Then, between parties should be accomplished their target equitably.

• International Journal of Quality Innovation
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• 제4권1호
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• pp.1-19
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• 2003

This paper describes the origins, evolution of Quality Function Deployment and its transfer to the West. Following a comprehensive review of the literature and how QFD has been defined, and applied, the paper analyses the critical factors which impinge on QFD implementation success. A discussion which covers the enabling criteria found to be inherent in Japanese applications is contrasted with the Western approaches documented hitherto. In particular the Company Wide Quality Control (CWQC) approach in Japan versus the emerging concept of Total Quality Management and their impact on QFD implementation. A critical analysis of the main differences isolated from the review of the literature and which characterise the Japanese method of QFD implementation which is leading, and The Western approaches which appear to be lagging is included in the paper, together with some useful conclusions:

• Journal of Multimedia Information System
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• 제3권3호
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• pp.47-52
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• 2016

This research paper examines the usage of graphic imaging in Holographic Projections to further advance the medical field. It highlights the importance and necessity of this technology as well as avant-garde techniques applied in the process of displaying images in digital holography. This paper also discusses the different types of applications for holograms in society today. Different tools were utilized to transfer a set of a cancer patient's brain tumor data into data used to produce a 3D holographic image. This image was produced through the transfer of data from one program to another. Through the use of semi-automatic segmentation through the seed region method, we were able to create a 3D visualization from Computed Tomography (CT) data.

• International Journal of Knowledge Content Development & Technology
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• 제4권2호
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• pp.5-23
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• 2014

The instant messenger (IM) is frequently encountered as a facilitator of communication in both social and working contexts. Nevertheless, there are concerns about the extent to which IMs bring organizational benefits, thereby overcoming interruptions to work. In this study, we focus on how IM tools contribute to knowledge transfer at work, as well as their influence on team performance. Our research model is validated by a survey of work professionals (n=41) at a small sized company. Implications and conclusions are discussed.