• Steel and Composite Structures
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• v.8 no.5
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• pp.343-359
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• 2008

In the present study, an efficient method for the optimum design of three-dimensional (3D) steel framed structures is proposed. In this method, in addition to choosing the best position of columns based on architectural requirements, the optimum cross-sectional dimensions of elements are determined. The preliminary design variables are considered as the number of columns in structural plan, which are determined by a direct optimization method suitable for discrete variables, without requiring the evaluation of derivatives. After forming the geometry of structure, the main variables of the cross-sectional dimensions are evaluated, which satisfy the design constraints and also achieve the least-weight of the structure. To reduce the number of finite element analyses and the overall computational time, a new third order approximate function is introduced which employs only the diagonal elements of the higher order derivatives matrices. This function produces a high quality approximation and also, a robust optimization process. The main feature of the proposed techniques that the higher order derivatives are established by the first order exact derivatives. Several examples are solved and efficiency of the new approximation method and also, the proposed method for the best position of columns in 3D steel framed structures is discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.324-329
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• 2018

This study examined the effects of the contact position and structure of the test probe on its signal transmission characteristics. The contact position in the operating of the test probe was considered and then divided into the plunger inner contact and barrel inlet contact. The high frequency performance of the test probes was investigated for both contact positions. The signal transmission characteristics of the test probes with the structures of double, single, and out-spring was also analyzed. The insertion and return losses were calculated using the HFSS and the characteristic impedance of the test probes was analyzed using a Q3D simulation. The insertion loss of the barrel inlet contact was smaller than that of the plunger inner contact. The contact position of the test probe may result in a change in the high frequency performance. The out-spring probe has better frequency characteristics at -1 dB insertion loss and -10 dB return loss. The double probe and single probe have the same characteristic impedance with $30.8{\Omega}$. On the other hand, the out-spring probe has an impedance of $47.1{\Omega}$. The out-spring probe is closer to $50{\Omega}$ than the other probes and then shows higher signal transmission characteristics. The out-spring probe has superior high-frequency characteristics and is expected to be suitable for high-speed applications.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.883-886
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• 1998

In order to detect the user's gaze position on a monitor by computer vision, the accurate estimations of 3D positions and 3D motion of facial features are required. In this paper, we apply a EKF(Extended Kalman Filter) to estimate 3D motion estimates and assumes that its motion is "smooth" in the sense of being represented as constant velocity translational and rotational model. Rotational motion is defined about the orgin of an face-centered coordinate system, while translational motion is defined about that of a camera centered coordinate system. For the experiments, we use the 3D facial motion data generated by computer simulation. Experiment results show that the simulation data andthe estimation results of EKF are similar.e similar.

• Journal of the Korea Computer Industry Society
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• v.9 no.3
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• pp.105-114
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• 2008

We present an eye tracking system using a low cost 3D CMOS imager for 3D displays that ensures a correct auto stereoscopic view of position- dependent stereoscopic 3D images. The tracker is capable of segmenting the foreground objects (viewer) from background objects using their relative distance from the camera. The tracker is a novel 3D CMOS Image Sensor based on Time of Flight (TOF) principle using innovating photon gating techniques. The basic feature incorporates real time depth imaging by capturing the shape of a light-pulse front as it is reflected from a three dimensional object. The basic architecture and main building blocks of a real time depth CMOS pixel are described. For this application, we use a stereoscopic type of display using parallax barrier elements that is described as well.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.76-76
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• 2000

The calibration of the robot system with a visual sensor consists of robot, hand-to-eye, and sensor calibration. This paper describe a new technique for computing 3D position and orientation of a 3D sensor system relative to the end effect of a robot manipulator in an eye-on-hand robot configuration. When the 3D coordinates of the feature points at each robot movement and the relative robot motion between two robot movements are known, a homogeneous equation of the form AX : XB is derived. To solve for X uniquely, it is necessary to make two robot arm movements and form a system of two equation of the form: A$_1$X : XB$_1$ and A$_2$X = XB$_2$. A closed-form solution to this system of equations is developed and the constraints for solution existence are described in detail. Test results through a series of simulation show that this technique is simple, efficient, and accurate fur hand/eye calibration.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1871-1875
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• 1997

Crane operation is manually accomplished by skilled operators. Recently, the concept of automation is widely introduced in shipping and unloading operation using the overhead crane for the enhanced productivity. In this regards, we designed an angle detector and 3D position detectro which are key evices for this operation. As well as an intellignet control algorithm is developed for the implementation of swing free crane. The performance of the presented algorithm is tested for the swing angle and the position of the overheas crand. The control scheme adopts a feedback control of an angular velocity of swing in initial phase and then the fuzzy controller whose rule base is optimized by a genetic algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.128.6-128
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• 2001

In this paper, we present a methodology of sensing and control for a robot system designed to be capable of grasping an object and moving it to target point Stereo vision system is employed to determine to depth map which represents the distance from the camera. In stereo vision system we have used a center-referenced projection to represent the discrete match space for stereo correspondence. This center-referenced disparity space contains new occlusion points in addition to the match points which we exploit to create a concise representation of correspondence an occlusion. And from the depth map we find the target object´s pose and position in 3-D space. To find the target object´s pose and position, we use the method of the model-based recognition.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.79.4-79
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• 2002

Our goal is the development of a system that estimates the location of interested point in a room with accuracy and low cost. Non-contacting position estimating method is widely used in various areas. Among these methods, acoustic signal-based method is the cheapest and provides reasonably accurate estimation as a result of many research efforts. Most of the acoustic-signal-based three-dimensional location estimators such as 3D sonic digitizer are using the ultrasound, and are organized with two procedures; time-of-flight (TOF) estimation and localization estimation. Since the errors in estimating the TOF could be accumulated with that of localization estimate, accuracy of TOF estimate is as...

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.231-235
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• 2001

The single oral toxicity of JG-381 was studied in Sprague-Dawley rats of both sexes. In this study, rats were administrated orally with dosages of 267, 400, 600, 900 and 1350 mg/kg of JG-381. We daily examined number of deaths, clinical signs, body weights and gross findings for 14 days after JG-381 administration. When we administered different doses of 267, 400, 600, 900 and 1350 mg/kg, we found 1, 4, 4, 5 and 5 male rats died and 3, 5, 4, 5 and 5 female rats died within 1 day after administration, respectively. Some clinical signs (decrease locomotor activity, salivation, soft stool, prone position, lacrimation, crouching position, convulsion, ataxic gait, incontinence of urine) were also observed during the experimental period. Our findings suggest that oral L $D_{50s}$ (95% confidence limit) for male and female rats are 327 mg/kg (270~396 mg/kg) and 250 mg/kg (256~264 mg/kg), respectively.y.

• Journal of Sensor Science and Technology
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• v.23 no.3
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• pp.149-157
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• 2014

This paper considers the ability of counting and positioning multi-targets by using a mobile UWB radar device. After a background subtraction process, distinguishing between clutters and human body signals, the position of targets will be computed using weighted Gaussian mixture methods. While computer vision offers many advantages, it has limited performance in poor visibility conditions (e.g., at night, haze, fog or smoke). UWB radar can provide a complementary technology for detecting and tracking humans, particularly in poor visibility or through-wall conditions. As we know, for 2D measurement, one method is the use of at least two receiver antennas. Another method is the use of one mobile radar receiver. This paper tried to investigate the position detection of the stationary human body using the movement of one UWB radar module.