• International Journal of Automotive Technology
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• v.8 no.4
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• pp.403-411
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• 2007

This article describes a methodology based on experiments and 1D modeling work related to the exhaust system analysis of a small two-stroke engine. The primary goal of this work was to understand how the design criteria of a compact exhaust system influenced the exhaust port pressure, since its evolution controls not only engine performance but also exhaust emissions. On the experimental side, a fully instrumented 50cc two-stroke engine was used to check the behavior of three different exhaust systems. A problem related to instantaneous pressure measurements in unsteady, hot flow was detected and solved during the study. To build the 1D model of the three exhaust systems, experimental information on the steady flow and the impulse test rigs was obtained under controlled conditions in specific facilities. Accurate comparisons between measured and calculated exhaust port instantaneous pressures were obtained from the following different exhaust system configurations: a straight duct, a tapered pipe and the three compact exhaust systems. The last step in the method used this model to analyze the pressure waves inside the exhaust system and detect the influence of the geometric parameters. The results should lead to improvements in the design process of complex compact exhaust systems in two-stroke engines.

• KIEAE Journal
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• v.15 no.3
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• pp.75-82
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• 2015

Purpose: This paper tried to understand the architectural concept of Neo Corbusian architects who had succeed to the Le Corbusier's principles of modern architecture and developed into their own creative architecture and formed a big achievement in the contemporary architecture. As representative Neo Corbusian architects, Henri Cirianni, Alvaro Siza and Laurant Beaudouin were selected to study their own design concepts and principles. Method: Three step study was conducted for the paper; Firstly, investigated significant differences about modern architecture between Le Corbusier and three neo corbusian architects; Secondly, analyzed the architectural meanings of 'Plan Libre' and 'Promenade Architecture' of three neo corbusian compared to Le Corbusier's ones; Finally, deducted their own design process to integrate the architectural concept of 'Plan Libre', 'Promenade Architecture' and 'Natural Light into architectural design. Results: According to the results of the research, Henri Cirianni, Alvaro Siza and Laurant Beaudouin made a splendid progress of Corbusier's modern concept, and then, created his own originative architecture by combining Plan Libre', 'Promenade Architecture' and 'Natural Light.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.4
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• pp.51-58
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• 2008

This paper presents a new design of the precision stage for the reticle in lithography process and a low hunting control method for the stage. The stage has three axes for X, Y, ${\theta}_z$ those actuated by three voice coil motors individually. The designed reticle stage system has three gap sensors and voice coil motors, and supported by four air bearings and the forward/inverse kinematics of the stage were solved to get an accurate reference position. When a stage is in regulating control mode, there always exist small fluctuations(stage hunting) in the stage movement. Because the low stage hunting characteristic is very important in recent lithography and nano-level applications, a special regulating controller for ultra low hunting is proposed in this paper. Also this research proposed the 2-step transmission system for preventing the noise infection from environmental devices. The experimental results showed the proposed regulating control system reduced hunting noise as 35nm(rms) when a conventional PID generates 77nm(rms) in the same mechanical system. Besides the reticle stage has 100nm linear accuracy and $1{\mu}rad$ rotation accuracy at the control frequency of 8kHz.

• Women's Health Nursing
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• v.30 no.2
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• pp.107-116
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• 2024

Purpose: This study was conducted to develop a cultural competence scale for nurses regarding the lesbian, gay, bisexual, and transgender (LGBT) community and to test its validity and reliability. Methods: The study adhered to the 8-step process outlined by DeVellis, with an initial set of 25 items derived through a literature review and individual interviews. Following an expert validity assessment, 24 items were validated. Subsequently, a preliminary survey was conducted among 23 nurses with experience caring for LGBT patients. Data were then collected from a final sample of 322 nurses using the 24 items. Item analysis, item-total score correlation, examination of construct and convergent validity, and reliability testing were performed. Results: The item-level content validity index exceeded .80, and the explanatory power of the construct validity was 63.63%. The factor loadings varied between 0.57 and 0.80. The scale comprised five factors: cultural skills, with seven items; cultural awareness, with five items; cultural encounters, with three items; cultural pursuit, with three items; and cultural knowledge, with three items; totaling 21 items. Convergent validity demonstrated a high correlation, affirming the scale's validity. Internal consistency analysis yielded an overall reliability coefficient of 0.97, signifying very high reliability. Each item is scored from 1 to 6 (total score range, 21-126), with higher scores reflecting greater cultural competence in LGBT care. Conclusion: This scale facilitates the measurement of LGBT cultural competence among nurses. Therefore, its use should provide foundational data to support LGBT-focused nursing education programs.

• The KIPS Transactions:PartD
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• v.15D no.5
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• pp.705-712
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• 2008

Recently, interests in the notion of PKMS(Process based on Knowledge Management System) utilizing BPMS(Business Process Management System) and KMS(Knowledge Management System) have been significantly increased. Specially, most public organizations require their own effective knowledge management strategies since public business service needs various knowledge types. Based on a comprehensive framework that reflects lifecycle requirements of KMS and BPMS, we propose an PKMS system architecture, which performs step-by-step knowledge-providing strategy in public organization. To propose a PKMS architecture, this paper first investigates inter-relationships between public business and various knowledge types, and classifies knowledge types into three groups and then we suggest knowledge management strategies considering priority order among knowledge groups. Based on the proposed knowledge management, a PKMS system architecture can combine the advantages of the KM and BPM paradigms. This paper presents the PKMS system applied to employment insurance business part in real environment and demonstrated the advantages via inter-relationships between KM and BPM requirements.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.355-360
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• 2002

ElectroSlag Strip Overlaying (ESSO) process has been around since 1970. ESSO process had limited acceptance due to a few problems associated with the use of this process in its very early stage. Limited knowledge and, most significantly, poor quality of the equipment and welding flux gave the ESSO process a bad name. However, this process is well accepted today and used in North America, Europe and Japan. The ESSO process provides low dilution overlays at high deposition rates, excellent and consistent deposit chemistry with excellent surface quality, and virtually no defects. Capitan has taken this process one step further through extensive research and development of the process itself as well as the equipment. The improvement brought to the process warranted the issuance in May 2000 of an US patent. This study demonstrates the feasibility of this process with immediate positive production results. The main achievements of this work are as follows: $\textbullet$ Development of six various strip-flux combinations on three different base materials: carbon steel, $\frac{1}{4}$ Cr/.5 Mo and 2 $\frac{1}{4}$ Cr/l Mo, fully tested with: penetrant, ultrasound, bends, hardness, overlay chemistry, corrosion and hydrogen disbonding. $\textbullet$ 12" dia. 90 hot formed elbows from straight pipe electroslag overlayed with "1 layer" and "2 layer" Alloy 625 $\textbullet$ a very unique development of miniaturized overlaying equipment able to perform overlay in pipe with diameters as low as 10" (254 mm). This development has large applications in the field of offshore, petrochemical, refining, pulp and paper and power generation industries. The aftermath of this development was its immediate acceptance by major end users with the completion of four projects of overlayed pipe in the USA and Far East Asia.

• Transactions of Materials Processing
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• v.24 no.4
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• pp.227-233
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• 2015

In this paper, the effect of flow stress, friction, temperature, and velocity on finite element predictions of metal flow lines after cylindrical upsetting is presented. An actual three-stage hot forging process involving an upsetting step is utilized and experimental metal flow lines are measured to study the effect of the various process variables. It was found that temperature and velocity for reasonable values of friction have little influence on metal flow lines especially those located deep within the cylinder but that flow stress has a direct influence on the flow lines. It was shown that a pure power law material model cannot reflect the real flow stress of hot material because it underestimates the flow stress especially around the dead-metal zone for the upsetting of a cylindrical specimen. It is thus recommended that a proper lower limit of flow stress be assumed to alleviate this issue.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.119-126
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• 2003

This paper presents an algorithm of automatically finding magnitude of each maintenance index regarding step response characteristic for speed control system of driving roller in rolling process. For speed response data with noise, we distinguished possible cases that the number of maximum values is 2 or more into three separate types. Also, we suggested a way of selecting a candidate for reasonable maximum overshoot in each type and developed a decision algorithm of checking whether a candidate chosen is correct maximum overshoot. In terms of two types of test, we showed that magnitude and position in time axis of maximum overshoot can be found well via such algorithm presented in this paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.15-19
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• 2001

A dedicated reverse engineering(RE) system for rapid manufacturing of human head in a 3D bust has been developed. The first step in the process is to capture the surface details of a human head and shoulder by three scanners based upon the digital moire fringe technique. Then the multiple scans captured from different angles are aligned and merged into a single polygonal mesh, and the aligned data set is refined by smoothing, subdividing or hole filling process. Finally, the refined data set is sent to a 4-axis computer numerically control(NC) machine to manufacture a replica. In this paper, we mainly describe on the algorithms and software for aligning multiple data sets. The method is based on the recently popular Iterative Closest Point(ICP) algorithm that aligns different polygonal meshes into one common coordinate system. The ICP algorithm finds the nearest positions on one scan to a collection of points on the other scan by minimizing the collective distance between different scans. We also integrate some heuristics into the ICP to enhance the aligning process. A typical example is presented to validate the system and further research work is also discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.5 s.236
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• pp.568-576
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• 2005

A 3-D finite element model combined with a volume tracking method is presented in this work to simulate the mold filling for casting processes. Especially, the analysis involves an adaptive grid method that is created under a criterion of element categorization of filling states and locations in the total region at each time step. By using an adaptive grid wherein the elements, finer than those in internal and external regions, are distributed at the surface region through refinement and coarsening procedures, a more efficient analysis of transient fluid flow with free surface is achieved. Adaptive grid based on VOF method is developed in tetrahedral element system. Through a 3-D analysis of the benchmark test of the casting process, the efficiency of the proposed adaptive grid method is verified. Developed FE code is applied to a typical industrial part of the casting process such as aluminum road wheel.