• Journal of the Korean Society for Precision Engineering
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• v.13 no.4
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• pp.122-128
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• 1996

In high speed and high precision assembly systems such as a surface mounting device and robotend effector, the contact force control is required. As the operation repeats, the repetitive control is applied to reduce the periodic contact force errors. Since high order unmodelled dynamics are easily excited in contact force control, a Q filter was introduced and its robust stability was analyzed. Simulation and Experimental results show the effectiveness of the algorithm.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.133-139
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• 1974

The objective of this study is to compare the effects of raw materials as method of speeding up mounting of matured silkworm, for reducing concentrated labor during mounting periods. The results obtained from this study are summarized as fellows： (1) Quercus acutissima Carrs showed the most remarkable effect of repellent. Persicaria blumei Gross and Artemisia asiatica Nakai were followed in order. The rest repellents were also expected to be applicable. considering known material (silk-up) with lower mounting percentage. (2) The effective methods of preparation of repellent were to make distillate. Decocted solution type was considered to be the easiest way of preparation. (3) It seemed to be that there was little effect of repellent on the qualities of cocoon and silk. (4) When a repellent was applied to a silkworm bed, immatured silkworms were observed to mount. Thus it suggests that the repellent will give remarkable effects only when the degree of matured of silkworms is uniform.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.4
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• pp.239-244
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• 2003

The common errors in preoperative treatment plan for the orthognathic surgery can be occurred during cast impression, cast mounting procedure with face-bow transfer, surgical stent fabrication, and so on. One of the most common errors exists during mounting process of the model on the articulator. Accurate mounting of dental casts to articulator should be achieved by transferring the 3-dimensional spatial relationship of the maxillary arch to an articulator. A face-bow is used for transfer this relationship to articulator, usually by relating the face-bow to a plane of reference of maxillary cast. The purpose of this study is evaluation of the accuracy of face-bow transferring of maxillary model to the articulator. The maxillary casts of thirty patients for orthognathic surgery were mounted on articulator with an face-bow instrument. The relationship of occlusal plane angle to Frankfort horizontal plane relations were compared the cephalogram with the cast-mounted articulator. As a result of this study, the significant difference between the maxillary occlusal planes angle in the cephalogram and articulator were found. The results were followed, 1. The mean occlusal plane angle in cast-mounted articulator was $13.5^{\circ}\;(SD{\pm}5.4)$. 2. The mean occlusal plane angle in cephalogram was $10.4^{\circ}\;(SD{\pm}4.3)$. 3. The mean difference of occlusal plane angle between cast-mounted articulator and cephalogram was $3.3^{\circ}\;(SD{\pm}4.6)$. According to the result, we should suggest that the occlusal plane angle to Frankfort plane in cast-mounted articulator is more steeper than that of cephalogram. And then, maxillofacial surgeon should try to get a more predictable result by suggesting the proper correction method and mounting the cast accurately.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.10
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• pp.915-921
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• 2017

Recently, studies to reduce vibration and noise of automobiles have been actively conducted. However, previous studies did not concentrate on the optimization of the mount system with passive or active mounts. This study analytically studies an active mounting system with three active structural paths between source and receiver and the feasibility has been verified. Active mounting system has a coupled structure of piezoelectric stack actuators and passive mounts. A dynamic model of the whole system is prepared and the control force and phase of the stack actuators in each path are determined to target full isolation of each path. Its performance on vibration attenuation is investigated and based on it, optimized combinations of passive and active paths for the best attenuation are presented.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.11
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• pp.1037-1046
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• 2013

In this study, the establishment of the criteria for accurate measurement is investigated via a statistical analysis of experimental results. The magnitude of influence on measurement errors is severely affected by the number of paths, mounting angle of sensor, straight pipe length in sequence, and Reynolds number. Three-dimensional numerical analysis has been conducted to understand the flow patterns downstream of a double bent pipe. Numerical analysis shows that the results well agreed with the experimental ones in case of a sensor mounting angle of $0^{\circ}$ and L/D = 3, 5 of $45^{\circ}$, $135^{\circ}$ in a single path. As a result, when the Reynolds number is 700,000-1,400,000, the sensor error of a single-path ultrasonic flowmeter is reduced with the mounting condition of L/D = 3, $45^{\circ}$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.338-344
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• 2021

In this study, an actual test procedure was considered for the effective operation of a bulletproof test. The problems of the existing system were drawn in two ways. First, it is difficult to mount items of various shapes. Second, various test standards cannot be applied. To improve these problems, an automated and standardized mounting system was designed/applied to mount various items. The multi-purpose mount was compatible with the backing support for body armor testing. The sample holding frame was located inside and was designed to mount samples of various sizes and shapes through vertical movement and fixation without a separate detachment/attachment process. A comparison of the economics before and after the introduction of the item mounting system confirmed the effectiveness of the system by the increased number of daily tests and equipment utilization and reduced hourly cost.

• Journal of Power System Engineering
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• v.12 no.2
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• pp.23-28
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• 2008

The primary objective of this study is to truly understand reaction force be due to engine exciting force. Exciting forces of the engine apply a source of the vehicle NVH(Noise, Vibration, Harshness). To understand reaction force was applied MSC.Nastran software. Analyzed frequency response analysis of powertrain mount system. First, engine exciting force was applied field function. Also nonlinear characteristics was applied field function : such as dynamic spring constant and loss factor. And nonlinear characteristics was applied CBUSH. Generally characteristics of rubber mount is constant frequency. But characteristics of hydraulic mount depend to frequency. Therefore nonlinear characteristics was applied. Powertrain mounting system be influenced by powertrain specification, mount position, mount angle and mount characteristics etc. In this study, we was analyzed effects of powertrain mounting system. And we was varied dynamics spring constant and loss factor of mounts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.515-518
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• 2006

A vibration test for a cylindrical rod inserted on the grid support structure was tested using the sine sweep excitation method with closed loop force control. The effect of the mounting location of a test rod on the vibration characteristics of a rod continuously supported by the full size($16{\times}16$) grid support was identified. An electromagnetic vibration shaker, non-contact displacement sensor and HP/VXI data acquisition device were used and TDAS software was also used as a data sampling and processing tools. The natural frequencies and mode shape of the test rod were consistent with the previous works of a rod vibration test with partial grids($3{\times}3,\;5{\times}5\;and\;7{\times}7$). The frequency characteristics of the rod according to the mounting location were shown clear discrepancies, but mode shapes were nearly same. As the test rod closes to the bottom clamping region of the spacer grid, peak vibration amplitudes of the rod become smaller.

• Journal of Sericultural and Entomological Science
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• v.33 no.2
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• pp.97-99
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• 1991

Disinfection of the rotatory cocooning frame is difficult under a multiple rearing system as the work is successively done. Accordingly, to investigate the effect of formalin fumigation on the rotatory cocooning frame during mounting period the mulberry leaves smeared with the water extract of dust collected form cocoonin frame after treatement were fed on the just molted 3rd instar larvae, 82% of them died with disease during 6 days, and negative effect of formalin fumigation takes place in terms of the cocoon reelability, showing 41% of it.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.6
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• pp.138-144
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• 2010

If the vibration is occurred in a large-sized bus roof, it makes people annoying and complaining the quality of a large-sized bus. So in design stage, it must be considered. To assess vibration at the roof which is equipped with air conditioner in design stage, finite element model is constructed. Computer simulation analysis and experimental method are performed. The dynamic characteristics of the large-sized bus are found by using eigenvalue method. It is related with dynamic behavior. The running conditions of a large-sized bus are velocity and road condition which followed experimental conditions. And the frequency response of a large-sized bus is well correlated with analysis result. Modal participation method is used for finding major modes at each peak. Using this method, we found that front and rear suspension system, engine mounting system and roof structure are the major reasons of the roof vibration. To reduce vibration level of roof in a large-sized bus, spring stiffness of front and rear suspension system, spring stiffness of engine mounting system and roof structure are properly combined. From this study, the vibration characteristics of the roof structure of a large-sized bus can be to a satisfactory level.