• The Plant Pathology Journal
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• v.28 no.1
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• pp.40-48
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• 2012

$Potato$ $virus$ $X$ (PVX) replication is precisely regulated by regulatory viral sequences and by viral and/or host proteins. In a previous study, we identified a 54-kDa cellular tobacco protein that bound to a region within the first 46 nucleotides (nt) of the 5' non-translated region (NTR) of the viral genome. Optimal binding was dependent upon the presence of an ACCA sequence at nt 10-13. To identify host factors that bind to 5' NTR elements including AC-rich sequences as well as stemloop 1 (SL1), we used northwestern blotting and matrixassisted laser desorption/ionization time-of-flight mass spectrometry for peptide mass fingerprinting. We screened several host factors that might affect PVX replication and selected a candidate protein, $Nicotiana$ $tabacum$ WRKY transcription factor 1 (NtWRKY1). We used a $Tobacco$ $rattle$ $virus$ (TRV)-based virus-induced gene silencing (VIGS) system to investigate the role of NtWRKY1 in PVX replication. Silencing of $WRKY1$ in $Nicotiana$ $benthamiana$ caused lethal apical necrosis and allowed an increase in PVX RNA accumulation. This result could reflect the balancing of PVX accumulation in a systemic $N.$ $benthamiana$ host to maintain PVX survival and still produce a suitable appearance of mosaic and mottle symptoms. Our results suggest that PVX may recruit the WRKY transcription factor, which binds to the 5' NTR of viral genomic RNA and acts as a key regulator of viral infection.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.393-398
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• 2007

Balance shaft has a key role in reducing a engine vibration in a vehicle and widely applied for current models. Since balance shaft module consists many sub-component and each part had its own operational characteristics, some different analysis background should be integrated into one sub-part in balance shaft module and this is the main obstacles in making a design process. Moreover, the balancing shaft rotating in high speed and such condition requires large safety factors in a design process owing to a lot of unexpected problems with the overwhelming rotation. Balance shaft is the core-component generating the intended unbalance as well as canceling the unbalance force or moment by the engine module. So, the balance shaft should meet the high fatigue resistance not to mention of NVH performance. In this paper, a design strategy focused on balance shaft is developed to build a optimal model considering a engine vibration. Putting the unbalance mass distribution as main design parameter, some candidate model is verified with structural and fatigue analysis most appropriate model is proposed here.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.11
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• pp.1387-1395
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• 2013

When the center of mass of a railway wheel is not aligned with the geometrical center of the wheel axis, wheel unbalance occurs. If a railway vehicle runs without removing the wheel unbalance, vibrations will be produced. This will also cause wear and damage of the axle bearing. In this study, dynamic analysis of a railway vehicle with wheel unbalance was conducted to examine the reduction in critical speed and the resonance of the car-body and the effect on the magnitude of wheel unbalance was examined. In addition, the calculation of the car-body vibration owing to static and dynamic unbalance in the railway wheel shows that two-plane balancing is necessary.

• Journal of Power System Engineering
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• v.12 no.1
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• pp.41-46
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• 2008

The primary objective of this study is to truly understand exciting forces of the in-line 4 cylinders engine. Exciting forces of the engine apply a source of the vehicle NVH(Noise, Vibration, Harshness). To understand exciting forces, first was governed theoretical equations for single cylinder engine. And this theoretical equations was programming using MATLAB software. To compare theoretical analysis value, was applied MSC.ADAMS software. To determined the specification of engine(2,000cc, in-line 4) was applied ADAMS/Engine module. And this specification for engine was applied ADAMS/View and MATLAB software. The geometry model for ADAMS/View analysis was produced by the 3-D design modeling software. After imported 3-D model, each rigid body was jointed suitable. Under idle speed for engine, was analysed. The results of analysis are fairly well agreed with those of three analysis method. Using MATLAB software proposed in this study, engine exciting fores can be predicted. Also using ADAMS/Engine module and ADAMS/View software, engine exciting forces can be predicted.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.7
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• pp.688-694
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• 2010

This paper presents a gravity compensator for the manipulator of a service robot. The manipulator of a service robot is operated with low velocity for the safety reason in most cases. In this situation gravitational torques generated by the mass of links are often much greater than dynamic torques for motion. A gravity compensator can counterbalance the gravitational torques, thereby enabling to utilize relatively low power motors. In this paper the gravity compensation for the roll-pitch rotation is considered which is often used for the shoulder joints of the manipulator of a service robot or humanoid robot. A gimbals is implemented and two 1-dof gravity compensators are equipped at the base. One compensates the gravitational torque at the roll joint and another provides the compensational torque for the gimbals. Various analyses showed that the proposed compensator can counterbalance the gravitational torques of 87% at the pitch joint and 50% at the roll joint. It is verified from dynamic simulations that the proposed compensator effectively counterbalances the gravitational torques.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1529-1534
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• 2008

Recently, mixers are being widely used in the display and semiconductor company in order to mix the chemical materials. The mixer normally consists of shaft, hub, reduction gear, and driving motor. It is one of the key design factors to evaluate the dynamic characteristics caused by the rotation. In this study, the dynamic characteristics of the high speed mixer, such as vibration, noise and thermal radiation, are verified by the experiment. Through the experiment, it is shown that the structural unbalance mass of high speed mixer is the important source of the severe vibrations and maximum temperature is mixer bowl.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.4
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• pp.764-774
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• 2002

Dynamic behaviors are analyzed for an automatic ball balancer (ABB) with triple races, which is a device to reduce the unbalanced mass of optical disk drives (ODD) such as CD-ROM or DVD drives. The nonlinear equations of motion are derived by using Lagrange's equations with the polar coordinate system. It is shown that the polar coordinate system provides the complete stability analysis while the rectangular coordinate system used in other previous studies has limitations on the stability analysis. For the stability analysis, the equilibrium positions and the linearized perturbation equations are obtained by the perturbation method. Based on the linearized equations, the stability of the system is analyzed around the equilibrium positions; furthermore, to confirm the stability, the time responses for the nonlinear equations of motion are computed by using a time integration method and experimental analyses are performed. Theoretical and experimental results show a superiority of the ABB with triple races.

• Korean Journal of Applied Biomechanics
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• v.30 no.4
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• pp.301-309
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• 2020

Objective: This study aimed to investigate the effect of white noise on dynamic balance in patients with stroke during walking. Method: Nineteen patients with chronic stroke (age: 61.2±9.8 years, height: 164.4±7.4 cm, weight: 61.1±9.4 kg, paretic side (R/L): 11/8, duration: 11.6±4.9 years) were included as study participants. Auditory stimulus used white noise, and all participants listened for 40 minutes mixing six types of natural sounds with random sounds. The dynamic balancing ability was evaluated while all participants walked before and after listening to white noise. The variables were the center of pressure (CoP), the center of mass (CoM), CoP-CoM inclined angle. Results: There is a significant increase in the antero-posterior (A-P) CoP range, A-P inclination angle, and gait speed on the paretic and non-paretic sides following white noise intervention (p<.05). Conclusion: Our findings confirmed the positive effect of using white noise as auditory stimulus through a more objective and quantitative assessment using CoP-CoM inclination angle as an evaluation indicator for assessing dynamic balance in patients with chronic stroke. The A-P and M-L inclination angle can be employed as a useful indicator for evaluating other exercise programs and intervention methods for functional enhancement of patients with chronic stroke in terms of their effects on dynamic balance and effectiveness.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.132-137
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• 2022

In this paper, we have studied the quadrature error reduction for the single drive 3-axis MEMS Gyroscope. There was a limitation of the previous study which is the z-axis quadrature error was large. To reduce this value, design methodologies were presented. And the methodologies included a different mesh application, z-rate spring structure change, and mass compensation for balancing of the structure. We conducted the modal analysis, drive mode analysis and sense mode analysis using COMSOL Multiphysics. As a result, a drive resonant frequency was 26003 Hz, with the x-sense, y-sense, z-sense being 26749 Hz, 26858 Hz, 26920 Hz, respectively. And the Mechanical sensitivity was computed at 2000 degrees per second(dps) input angular rate while the sensitivity for roll, pitch, and yaw was computed 0.011, 0.012, and 0.011 nm/dps respectively. And z-axis quadrature error was successfully improved, 2.78 nm to 0.95 nm, which the improvement rate was about 66 %.

• Korean Journal of Community Nutrition
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• v.6 no.1
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• pp.51-68
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• 2001

This investigation studied the relationship between Body Mass Index(BMI) and dietary intake, levels of serum lipid, lipoprotein(a) and plasminogen activator inhibitor-1(PAI-1) of 28.449 Korean adults(16.937 men, 11.542 women) from 1995 to 1999. The dietary assessment was conducted using 24-hour dietary records and food frequency questionnaires. During this five year study, the BMI normal-weight group, as a percentage of the annual test population, decreased from 68.0% to 60.2%, while the BMI overweight and obese groups collectively increased from 25.0% to 29.7%. The levels of serum total cholesterol (TC), LDL-cholesterol(LDL-C), Triacylglycerol(TG) and PAI-1 increased as the values of BMI increased, while the levels of HDL-cholesterol(HDL-C) and lipoprotein(a)(men only) appeared to decrease as values of BMI increased. The levels of daily energy intake also increased as values of BMI increased in both men and women. The obese group had significantly higher levels of carbohydrate, protein, fat(men only), and cholesterol intake than those of the normal-weight, underweight, and overweight groups. In men, BMI positively correlated with the levels of macronutrients and cholesterol intake(p＜0.001), % energy of protein, fat, and alcohol intake(p＜0.001), and the levels of serum TC, LDL-C, TG and PAI-1(p＜0.001), while BMI negatively correlated with % energy of carbohydrate intake, and the levels of Lp(a) and HDL-C(p＜0.001). In women, BMI negatively correlated with level of cholesterol(p＜0.01), fat(p＜0.001), alcohol intake(p＜0.05),% energy of fat (p＜0.001), % energy of alcohol intake and level of and HDL-C(p＜0.001). Subjects who had serum TC, LDL-C, HDL-C, and TG levels greater than the standard reference values(TC＞240mg/㎗, LDL-C＞130mg/㎗, HDL-C＞35, TG＞200mg/㎗) exhibited a higher intake of the three macronutrients, iron, calcium, meat, milk and fatty foods than those subjects who had serum lipid concentrations less-than-or-equal-to the standard reference values. Overall, there was positive correlation between the high risk factors of vascular disease variables, dietary intake, and BMI. Prevalence of hypertension and high blood sugar were increased as BMI increased, but the prevalence of hypertension is decreased as the year goes by. These findings showed that dietary intake, level of serum lipids and other vascular disease risk factors increased as BIM increased. Therefore, middle or upper class Korean adults who have high BMI should improve their eating habits. This involve reducing alcohol, animal fat, high carbohydrate foods, and overall food intake, and balancing intake in order to lower vascular disease risk factors, including obesity.