• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.151-152
• /
• 2006

Nowadays, great attention has been shown to the question of ultrasonic linear motor for accomplishing the high positioning accuracy and high driving force in the semiconductor and optical industry. Ultrasonic linear motors have many advantages such as simple structure, quick response, ability to maintain position without energy consumption, and electromagnetic effect. And BLT has attracted attention to accomplish large vibration amplitude and large mechanical force. Authors designed and developed the new type of ultra sonic linear motor with multi support mechanism, achieved 75N of output force and 0.45m/s of velocity.

• Proceedings of the KIEE Conference
• /
• 2003.07b
• /
• pp.1048-1050
• /
• 2003

Recently, many linear motion generators and motors are rapidly finding applications that ranges from short stroke linear motion vibrators, such as dynamic con type loud speakers to stilting engine driven linear reciprocating alternators, compressors, textile machines etc. In this paper, we analyze the characteristics of tubular linear motor with Halbach and radial magnet array respectively. We already derived magnetic field solutions due to the PMs and to the currents and Motor thrust. On the basis of analytical field solutions, this paper deals with flux linkages and back emf. The results are validated extensively by comparison with finite element analyses. Then, this parer also presents thrust characteristics according to design parameters for each model.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1462-1464
• /
• 2005

The demand for linear electrical machines, for both controlled motion and electrical power generation, has increased steadily in recent years. For example, for applications in the high-speed packaging and manufacturing sectors, linear electromagnetic machines, which provide thrust force directly to a payload without the need to convert rotary to linear motion, offer significant advantages in terms of simplicity, efficiency, positioning accuracy, and dynamic performance in both acceleration capability and bandwidth. So, this paper describes analysis the dynamic characteristics of Tubular Type Linear BLDC Motor by simulation and experiments.

• Journal of Animal Science and Technology
• /
• v.52 no.6
• /
• pp.467-473
• /
• 2010

A total of 4,323,781 records for informal 16 primary linear descriptive traits of dairy cows in Holstein breed from 1988 to 2007 in USA were analyzed to estimate adjustment factors for lactation number and stage. While all factors in the model were highly significant (P < 0.01), major influences on linear type traits were due to lactation number and stage. The frequencies of lactation number 1 through 6 were 58.6, 22.0, 11.8, 4.8, 2.1, and 0.8%, respectively. Further, the frequencies of lactation stage were 0.7, 76.9, 15.3, 4.9, and 2.1%, respectively, for springing, early, medium, late, and dry. To adjust 16 linear traits (stature, dairy form, strength, body depth, rump width, rump angle, legs rear view, leg set, foot angle, fore udder, rear udder height, rear udder width, udder support, udder depth, and front teat placement), additive and multiplicative adjustment factors of lactation number (lactations 2 to 4) and stage (springing, medium, late and dry) were estimated with the solutions in the generalized linear model, assigning lactation 1 and stage early as base class. Additive adjustment factors of lactation number ranged from -1.23 to 2.908, while multiplicative factors ranged from 0.853 to 2.207. Further, additive and multiplicative adjustment factors for lactation stage ranged from -0.668 to 0.785, and from 0.891 to 1.154. Application of adjustment factors to 20 randomly sampled sub-data sets produced the results that additive adjustment factors for both lactation number and stage reduced more mean square of lactation number and stage over 16 linear traits than any combination of adjustments, and leaded additive adjustment factors for both lactation number and stage as a choice of methods for adjustment of informal 16 primary linear type traits collected by classifiers of AI studs.

• 전기의세계
• /
• v.43 no.5
• /
• pp.36-43
• /
• 1994

본문에서는 EML의 역사, 종류와 대강에 대해 설명하고, 필자가 미국에서 직접 연구에 참여한 linear induction type coil gun에 대해 간단히 언급하기로 한다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.1306-1310
• /
• 2009

The roughness coefficients were estimated by the Manning's equation for the measured stage and flow velocity of Bocheong stream basin in Kum river. The relationships between the estimated roughness coefficients and the geomorphologic factors were formulated by the linear, logarithmic, exponential and power type function, thereafter correlation equations were presented. The correlation analysis was performed between the measured stream length and the basin area of Bocheong stream basin by the linear, logarithmic, exponential and power type function, and correlation equation for the stream length was given. The roughness coefficient has strong correlationship with stream slope, but low correlation coefficients with stream length and basin area. For the correlationship with the roughness coefficients and the stream slope, the logarithmic type function has the smallest correlation coefficient, on the other hand, the exponential type function has the largest correlation coefficient. For the relationship between the stream length and the basin area, the correlation coefficient of the logarithmic type function shows the smallest value, linear type function shows the largest value.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.1380-1383
• /
• 2004

The scanning type XY stage is frequently used these days as precision positioning system in equipment for semiconductor or display element. It is requested higher velocity and more precise accuracy for higher productivity and measuring performance. The position accuracy of general stage is primarily affected by the geometric errors caused by parasitic motion of stage, misalignments such as perpendicular error, and thermal expansion of structure. In the case of scanning type stage, H type frame is usually used as base stage which is driven by two actuators such as linear motor. In the point view of scanning process, the stage is used in moving motion. Therefore, dynamic variation is added as significant position error source with other parasitic motion error. Because the scanning axis is driven by two actuators with two position detectors, 2 dimensional position errors have different characteristic compared to general tacked type XY stage. In this study 2D position error of scanning stage is analyzed by 1D heterodyne interferometer calibrator, which can measure 1D linear position error, straightness error, yaw error and pitch error, and perpendicular error. The 2D position error is evaluated by diagonal measurement (ISO230-6). The yaw error and perpendicular error are compensated on the base stage of scanning axis. And, the horizontal straightness error is compensated by cross axis compensation. And, dynamic motion error in scanning motion is analyzed.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.11
• /
• pp.1527-1530
• /
• 2002

Factor analysis was applied to the phenotypic correlation matrix of 15 linear type traits (scored linearly 1 to 50 points) for 2035 Holstein cows of 38 sires computed from data collected between 1988 and 1992 in Beijing Shuangqiao Farm and Beijing Xijiao Farm. The 15 linear type traits were stature, body strength, body depth, dairy form, rump angle, rump length, rump width, rear leg side view, foot angle, fore udder attachment, rear udder height, rear udder width, udder cleft, udder depth and teat placement rear view. The first four components accounted for 49.1% of the total variance in type scores. Factor 1 reflected strong cows, with deep bodies, with long and wide rumps, and tall in stature. Factor 2 reflected cows with well attached fore udders, wide rear udders and whose udders were supported by strong suspensory ligaments with close teat placement. Factor 3 reflected cows with good dairyness, sickled in the hocks, high rear udders and udder floors above the hocks. Factor 4 reflected cows with sloping rumps from hooks to pins and with steep foot angle. Principal component and factor analyses are useful to clarify the relationships among type traits.

• Journal of applied mathematics & informatics
• /
• v.29 no.5_6
• /
• pp.1067-1074
• /
• 2011

In this paper, a preconditioned mixed-type splitting iterative method for solving the linear systems Ax = b is presented, where A is a Z-matrix. Then we also obtain some results to show that the rate of convergence of our method is faster than that of the preconditioned AOR (PAOR) iterative method and preconditioned SOR (PSOR) iterative method. Finally, we give one numerical example to illustrate our results.

• Journal of applied mathematics & informatics
• /
• v.9 no.2
• /
• pp.531-542
• /
• 2002

In this paper we deal with a sequence of positive linear operators ${{R_n}}^{[$\beta$]}$ approximating functions on the unbounded interval [0, $\infty$] which were firstly used by K. balazs and J. Szabados. We give pointwise estimates in the framework of polynomial weighted function spaces. Also we establish a Voronovskaja type theorem in the same weighted spaces for ${{K_n}}^{[$\beta$]}$ operators, representing the integral generalization in Kantorovich sense of the ${{R_n}}^{[$\beta$]}$.