• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.10 no.1
• /
• pp.1-9
• /
• 2001

The development of flexible automation in the manufacturing industry is concerned with production activities performed by unmanned machining system A major topic relevant to metal-cutting operations is monitoring toll wear, which affects process efficiency and product quality, and implementing automatic toll replacements. In this paper, the measurement of the cutting force components has been found to provide a method for an in-process detection of tool wear. The static com-ponents of cutting force have been used to detect flank wear. To eliminate the influence of variations in cutting conditions, tools, and workpiece materials, the force modeling is performed for various cutting conditions. The normalized force dis-parities are defined in this paper, and the relationships between normalized disparity and flank were are established. Final-ly, artificial neural network is used to learn these relationships and detect tool wear. According to proposed method, the static force components could provide the effective means to detect flank wear for varying cutting conditions in turning operation.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.17 no.11
• /
• pp.1093-1101
• /
• 2007

This study presents the design improvement process for door module. Its objective evades the resonance generated at module plate due to the operation of window regulator motor. For this study, the design improvement process is composed of experimental methods having three steps. First step is modal analysis at door assembly status for acquisition of dynamic characteristics which are modal frequency and damping. Second step is a vibration experiment to get the test mode considered an efficiency of window regulator motor. Last step is a vibration measurement by the form of $6{\times}6$ array on module plate. A vibration measurement of $6{\times}6$ array form can be got to three analysis results which are a transfer path of vibration using cross correlation function, a vibration map using OA level and a contribution by frequency band using coherent output power spectrum on module plate. These results are applied to SDM(structural dynamic modification) for design improvement to get around the resonance on module plate by the excitation of window regulator motor.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.48 no.7
• /
• pp.82-90
• /
• 2011

An accurate signal integrity verification method based on high-frequency measurements is proposed. For practical transmission lines that require a package process, process variations metal roughness and skin effects and boundary conditions may have deteriorative effects on circuit performance. These effects are represented in terms of parameters that can be readily utilized for field-solver. Thereby a more accurate signal integrity verification using field-solver can be achieved. It is shown that in both single and coupled lines the signal transients using the proposed method have excellent agreement with the measurement data.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.222-228
• /
• 2007

In order to solve the problem of traffic holdups and environmental pollution(contamination), several metropolises are operating the subway and many local government plans hereafter the light rail vehicle operation and it is in the process of preparing. This point of time, it need to evaluate the comfortable characteristic of the seat which is closely connected with passenger and it should be reflected to the product design through the data analysis. The methods of the comfortable characteristic evaluation should be considered to various methods from physical factor to psychological factor. Among these, the most universal and possible quantitative measurement estimate through 'Body pressure measurement system'. From this paper, it was measured the body pressure of the subway seat which is in the process of operating in a domestic and it will be compared and analyzed the material & seat shape, so we evaluated the comfortable characteristic of the short-distance transportation railway vehicle. It was operated the man and woman who belongs in standard shape of Korean, we compared and analyzed the Peak position where the body pressure is visible and body pressure spread out.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.1
• /
• pp.242-259
• /
• 2015

Three-dimensional video coding is one of the main challenges restricting the widespread applications of 3D video and free viewpoint video. In this paper, a novel fractal coding algorithm with motion-vector-field-based motion estimation for depth map sequence is proposed. We firstly add pre-search restriction to rule the improper domain blocks out of the matching search process so that the number of blocks involved in the search process can be restricted to a smaller size. Some improvements for motion estimation including initial search point prediction, threshold transition condition and early termination condition are made based on the feature of fractal coding. The motion-vector-field-based adaptive hexagon search algorithm on the basis of center-biased distribution characteristics of depth motion vector is proposed to accelerate the search. Experimental results show that the proposed algorithm can reach optimum levels of quality and save the coding time. The PSNR of synthesized view is increased by 0.56 dB with 36.97% bit rate decrease on average compared with H.264 Full Search. And the depth encoding time is saved by up to 66.47%. Moreover, the proposed fractal depth map sequence codec outperforms the recent alternative codecs by improving the H.264/AVC, especially in much bitrate saving and encoding time reduction.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.8 no.4
• /
• pp.97-103
• /
• 2009

Since a demand for an extensive range of earthmoving equipment like a hydraulic excavator with a capacity of 85tons has been asked in construction fields, a performance of its track drive unit has to be verified experimentally. Among the verification of the performances, a torque measurement is at issue, in which a torque meter is utilized widely. However, the very large scaled torque meter is necessary when a discharged torque from the track drive unit is increased significantly. In addition, the price for experimental set-up of a torque meter is too high due to its limitation of the geometry such as long length, and a break down in operation occurs frequently. In this study, to measure a high torque up to 200,000Nm, a new technique was proposed as an alternative of conventional measurement by using a torque meter. The new technique enables to measure the high torque stably in a compact space via a torque arm and two load cells. The experimental results showed a propriety of the proposed torque measuring technique for a track drive unit with very large capacity.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.8 no.3
• /
• pp.654-659
• /
• 2007

This study suggests a measure method for measuring variables that are used for hotel corporations' CRM performance. For this purpose, I present a combined method between factor analysis and AHP(Analytic Hierarchy Process) analysis. Factor analysis gives us a result that shows a group of highly correlated variables and another group of less correlated variables. Thus, factor analysis can only give information of factor categorization. Although researchers add ANOVA analysis or regression analysis, these efforts can not connect its results with factor analysis. Therefore, In hotel CRM performance analysis, calculation of each factor's importance is strongly required. For that reason, I suggest a method that combines AHP analysis with factor analysis for Hotel CRM performance measurement.

• Asian Journal of Atmospheric Environment
• /
• v.9 no.2
• /
• pp.137-145
• /
• 2015

This study focused on the measurement of the actual charging state of ambient aerosol particles, which is important for understanding the intricate process of adverse health effects caused by particulate matter (PM). The net electrostatic charging state of $PM_{2.5}$ collected on filter media was measured in this study. The Faraday cage method and surface potential measurements were used in this study. The results showed that the polarities of the net charging state measured using these two methods were in agreement for 42 out of 48 samples (87.5%), and 36 samples (75%) were negatively charged. The filters were not significantly charged by friction between the filters and air not containing PM. Charge addition to or leakage from the filters was not observed over a two-month storage period. Net charging state of $PM_{2.5}$ collected on the filters was concluded to be negative in most cases, based on data's support of the assumption that aerosol charging state is not altered by the process of PM collection using filter.

• Journal of the Korean Magnetics Society
• /
• v.27 no.4
• /
• pp.145-152
• /
• 2017

The arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) method that can evaluate tissue perfusion using blood in the body. The characteristic of non-invasive examinations without contrast agents and the quantitative measurement of perfusion volume is possible, which are increasingly being used for clinical and research purposes. Up to the present, The ASL method has lower SNR than the perfusion imaging method using contrast agent and because optimization of various parameter in the imaging process is difficult, Which may result in measurement errors. To improve this, ASL methods using various technologies are introduced. This paper briefly introduces the outline of ASL, its features in imaging process, various techniques, and clinical application.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.11
• /
• pp.843-851
• /
• 2020

This study focuses on identifying and prioritizing the broader performance measures for the service supply chains by taking the case of Majan Electricity Company, Sohar, in the Sultanate of Oman. For an examination of the uniformity of ultimate objectives and the priorities therein, two strata of respondents with a total of fourteen respondents were approached for their valuable insights. Suitable structured instruments were personally administered to elicit the insightful and worthy responses. The two multi-criteria decision-making techniques, namely, the Fuzzy Analytical Hierarchy Process and the Best-Worst Method were used to reach a meaningful prioritization of the identified and refined broader performance measurement dimensions. The results show that there exists a minor gap between the two respondents' groups in terms of their prioritizations. The major finding points to the difference in terms of the topmost priorities as revealed by the two set of respondents. For one group of respondents, the customer satisfaction matters the most, whereas for the other group, it is the overall profitability that matters the most. This gap against the utopian state assists in concluding that there is a requirement to reorient the employees so as to have a shared and common understanding of the organizational priorities.