• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.7
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• pp.1654-1663
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• 1994

Even if the ball bearing was conservatively designed considering the dynamic capacity and the rating life, sometimes the bearing was early failed on account of the misalignment and the lubricant contaminations etc. Misalignment was generated when bearing-shaft system transmitted large power and when the bearing was inadequately mounted. It was possible to predict the fatigue life of ball bearing under the misalignment considering the motions of ball, cage and raceway, and the factors of the effect on fatigue life. Misalignment affected on ball bearing as radial and moment load and the relationships between misalignment and moment were obtained. In this paper, the analysis of the load distributions between ball and raceway, and the prediction of fatigue life of deep groove ball bearing under radial and moment loads were carried out. And, the new formulation of equivalent dynamic load considering the effects of moment load was proposed.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.7
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• pp.841-847
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• 1999

For successful assembly of flexible parts, informations about their deformation as well as possible misalignments between the holes and their mating parts are essential. Such informations can be acquired from visual sensors. For robotic assembly, the corrective assembly motion to compensate for such misalignments has to be determined from the measured informations. However, this may not be simply derived from the measured misalignment alone because the part deformation progressively occurs during misalignment compensation. Based on the analysis of flexible parts assembly process, this paper presents a neural net-based inference system that can infer the complex relationship between the corrective motion and the measured information of parts deformation and misalignments. And it verifies the performance of the implemented inference system. The results show that the proposed neural net-based misalignment compensation algorithm Is effective in compensating for the lateral misalignment, and that it can be extended to the assembly tasks under more general conditions.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.79-84
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• 2001

The motivation behind this work is to understand the phenomenon of friction-induced vibration and squeal due to misalignment. In present paper, it is studied on effect of misalignment between friction-induced vibration and squeal by an experiment using a pin-on-disk type experimental apparatus. In order to build an analytical model of the friction-induced vibration system with misalignment, the system is modeled as a single-DOF and 3-DOF system. The results show that the single DOF system can only show stick／slip phenomenon, but the 3-DOF system can show squeal due to misalignment. Consequently, it can be said that the misalignment in a friction-induced vibration system is a source of squeal noise.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.636-643
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• 2009

NHC means that the velocity of the vehicle in the plane perpendicular to the forward direction is almost zero. The main error source of NHC is the mounting misalignment which is the difference between the body frame of a land vehicle and the sensor frame of an inertial measurement unit. This paper suggests new NHC algorithm that can reduce position errors by real-time estimation of mounting misalignment. Then NHC/ZUPT integrated land navigation system is designed and its performances are analyzed by simulations with van test data. Simulation results show that the proposed NHC/ZUPT land navigation system improves navigation accuracy regardless of misalignment angle and is very useful when SDINS operates stand-alone for land vehicle navigation with large mounting misalignment.

• Phonetics and Speech Sciences
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• v.1 no.4
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• pp.61-71
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• 2009

This study aims to investigate whether the misalignment between syllable and word onsets due to the process of resyllabification affects Korean-English late bilinguals perceiving English continuous speech. Two word-spotting experiments were conducted. In Experiment 1, misalignment conditions (resyllabified conditions) were created by adding CVC contexts at the beginning of vowel-initial words and alignment conditions (non-resyllabified conditions) were made by putting the same CVC contexts at the beginning of consonant-initial words. The results of Experiment 1 showed that detections of targets in alignment conditions were faster and more correct than in misalignment conditions. Experiment 2 was conducted in order to avoid any possibilities that the results of Experiment 1 were due to consonant-initial words being easier to recognize than vowel-initial words. For this reason, all the experimental stimuli of Experiment 2 were vowel-initial words preceded by CVC contexts or CV contexts. Experiment 2 also showed misalignment cost when recognizing words in resyllabified conditions. These results indicate that Korean listeners are influenced by misalignment between syllable and word onsets triggered by a resyllabification process when recognizing words in English connected speech.

• International Journal of Fluid Machinery and Systems
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• v.5 no.2
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• pp.91-99
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• 2012

The Fighter aircraft transmission system consists of a light weight, High Speed Flexible Coupling (HSFC) known as Power Take-Off shaft (PTO) for connecting Engine gearbox (EGB) with Accessory Gear Box (AGB). The HSFC transmits the power through series of specially contoured metallic annular thin flexible plates whose planes are normal to the torque axis. The HSFC operates at high speed ranging from 10,000 to 18,000 rpm. The HSFC is also catered for accommodating larger lateral and axial misalignment resulting from differential thermal expansion of the aircraft engine and mounting arrangement. The contoured titanium alloy flexible plates are designed with a thin cross sectional profile to accommodate axial and parallel misalignment by the elastic material flexure. This paper investigates the effect of misalignment on the transmission characteristics of the HSFC couplings. A mathematical model for the HSFC coupling with misalignment has been developed for analyzing the torque transmission and force interaction characteristics. An extensive testing has been conducted for validating characteristics of the designed coupling under various misalignment conditions. With this the suitability of the model adapted for the design iteration of HSFC development is validated. This method will reduce the design iteration cycles of HSFC and can be extended for the similar development of flexible couplings.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.63-73
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• 2021

This study investigates the key determinants of exchange rate (RER) misalignment for the period 1991 to 2020. The BEER technique has been used to estimate the degree of the equilibrium exchange rate. To explore the actual exchange rate misalignment and to assess the behavior of variables that are different in different regimes of undervaluation and overvaluation, the nonlinear technique of Markov regime-switching (MSM) was applied. The mean and variance of each regime are highly significant and show that undervaluation episodes have a low mean (116.139) and more volatility (1.229) while overvaluation episodes have a high mean (126.732) with less volatility (0.871). The findings show that MSM accurately identifies exchange rate misalignment in both regimes as separate incidents of overvaluation and undervaluation. Results further depict that misalignment of the RER is affected by terms of trade, net foreign assets, interest differential, government investment, and consumption decision. Results recommend that if policymakers want to use the exchange rate as a policy tool, they must first consider the drivers of the equilibrium exchange rate. As a result, any deliberate actions to address exchange rate misalignment must focus on the underlying fundamentals that drive the exchange rate.

• Tribology and Lubricants
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• v.36 no.1
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• pp.27-33
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• 2020

Self-equalizing tilting pad thrust bearings are usually employed in turbomachines to achieve high stability and reliability. A tilting pad bearing can incorporate self-equalizing links to handle the misalignment between the bearing and the thrust collar. In this popular design method, the pads sit on the upper-level plates and the lower-level plates stay on the retainer base. With misalignment, the pads that are heavily loaded are pushed down. Consequently, the link pushes up the pads on the opposite side, keeping the bearing surface parallel to the thrust collar surface. The self-equalizing link is used to handle the misalignment from the thermal and mechanical effects. In this study, the experimental investigation deals with the performance of self-equalizing tilting pad thrust bearings. The test rig for evaluating the performance of bearing is developed which can control the misalignment angle. Simultaneous measurements are taken for the force acting on each pad. Pad metal temperature and oil film thickness are functions of the shaft speed, bearing load, misalignment angle, and design of leveling plates. The effect of misalignment on bearing performance is discussed. The results demonstrate that the load on each pad depends on the test conditions(especially misalignment angle), and the load influences the performance of bearings.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1461-1469
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• 2011

Using three-dimensional (3-D) FE analyses, this paper provides a method for analyzing the effects on stresses and strains produced by angular and concentric misalignment of a test specimen for a torsion test. To quantitativele compare of the FE results, the average bending strain for the angular, concentric, and combined misalignment was proposed. To verify the effects of axial misalignment of the test specimens, we used both circular and tubular specimens. From the FE results, we proposed general predictions for the effects caused by the various types of axial misalignment and its direction. In addition, we confirmed the effect of initial yielding moment based on the initial yielding condition for axial misalignment of specimens in torsion tests.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.3
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• pp.71-74
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• 2013

In this study, the effects of wafer warpage on the misalignment during wafer stacking process were investigated. The wafer with $45{\mu}m$ bow height warpage was purposely fabricated by depositing Cu thin film on a silicon wafer and the bonding misalignment after bonding was observed to range from $6{\mu}m$ to $15{\mu}m$. This misalignment could be explained by a combination of $5{\mu}m$ radial expansion and $10{\mu}m$ linear slip. The wafer warpage seemed to be responsible for the slip-induced misalignment instead of radial expansion misalignment.