• Journal of the Korean Institute of Intelligent Systems
• /
• v.7 no.5
• /
• pp.67-76
• /
• 1997

In this paper, a theoretical study is presented for the force control of a miniature robotic manipulator which is driven by a pair of piezo-electric bimorph cells. In the theoretical analysis, one finger is modeled as a flexible cantilevers with a force sensor at the tip and the finger is a solid beam. The robotic finger is used to hold the objects with different stiffness such as an iron block and a living insect and a moving objcet. So it is very important to develop an adequate controller for the holding operation of the finger. The main problems in force controlling are overdamping, overshoot and unknown environment(such as the stiffness of object and unknown plant parameters). So, the main target is propose the new fuzzy compensation for unknown environment and incease the system performance. The fuzzy compensation is implemented by using PI-type fuzzy approach to identified unknown environment. And the result of proposed controller was compared with the conventaional PID and optimal controller.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2006.11a
• /
• pp.455-458
• /
• 2006

John Carmack who invented the 3D games let us know about the great 3D world and because of the MIDP 2.0(Mobile Information Device Profilers entering, it is not a fame to achieve playing 3D games with a mobile device. The data offered by iResearch market consultation show that the figure of mobile game players all around the world will take a steady increase from 290 million in 2005 to 1030 million in 2008, and the market income will mount up from $10,200 million to $52.000 million.3D games will be a current, the most famous kind of mobile games. In this paper I design 3D application based on J2ME (Java 2 Micro Edition) and implement a freely removable 3D object which happened in a 3D scene by receiving the keyboard response of mobile device with WTK (Wireless Too.Kit) simulator.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1722-1723
• /
• 2007

This paper describes a simple method to reduce rotation angle error of mobile robot using omni-wheel[3](omni-bot). This method can be applied to not only omni-bot, but also other robot with a large number of servo motor. Robot using many servo motor as omni-bot is complicated for hardware and software, each servo motor has difficulty in synchronizing. Three servo motor, three omni-wheel and three serial servo motor controller is used, PC or Micro Processor interface with the serial servo controller through "SSC100" protocol. In order to check the improvement of the proposed serial servo synchronization compared to existing sequential communication method. comparing object is rotation angle error of omni-bot. The results of this make building of omni-bot system easy and decrease rotation angle error.

• Proceedings of the KACD Conference
• /
• 2003.11a
• /
• pp.574-574
• /
• 2003

I. Objectives Newly all-in-one adhesives were developed for reducing the techique sensitivity and chair time, but lots of concerns were made on bondability, longevity, and microleakage. The object of this study was to measure micro leakage and marginal quality of all-in-one adhesives using electrochemical method and SEM analysis quantitatively. II. Materials and Methods After making Class V cavities, they were bulk filled with Heliomolar(＃A1) after surface treatment with three adhesives：Adper Prompt (Group 1), One up bond F (Group 2), Xeno III(Group 3).(omitted)

• Current Applied Physics
• /
• v.18 no.11
• /
• pp.1261-1267
• /
• 2018

In this paper, an off-axis digital holographic microscopy compensated with self-hologram rotation is presented. The process is implemented via subtracting the unwrapped phase maps of the off-axis parabolic hologram and its rotation $180^{\circ}$ to eliminate the tilt induced by the angle between the spherical object wave O and the plane reference wave R. Merit of the proposed method is that it can be done without prior knowledge of physical parameters and hence can reconstruct a parabolic hologram of $1024{\times}768$ pixels within tens of milliseconds since it doesn't require a digital reference wave. The method is applied to characterize rough gold bumps and the obtained results were compared with those extracted from the conventional reconstruction method. The comparison showed that the proposed method can characterize rough surfaces with excellent contrast and in realtime. Merit of the proposed method is that it can be used for monitoring smaller biological cells and micro-fluidic devices.

• International Journal of Advanced Culture Technology
• /
• v.10 no.3
• /
• pp.377-392
• /
• 2022

With the development of information and Internet technology, traditional museums have been long followed the trend of integrating innovative technological elements into the changed museums. It is necessary that the museums seize the opportunity of the trend transforming into smart museums, the key is to grasp the characteristics and laws of the Internet era, and use Internet thinking to explore the future development path. However, there are few studies on Internet thinking among the existing results. On the other hand, most of the relevant actual case studies still focus on the micro-level, which has obvious limitations. This paper will start from the current situation and trend, focus on the Palace Museum as a case study object, and discuss the problems and characteristics, so as to put forward the thinking about the development of smart museums in four aspects to explore the optimal path of transformation for smart museums.

• The Journal of the Korea Contents Association
• /
• v.9 no.11
• /
• pp.262-270
• /
• 2009

$^{18}F$-mefway has been developed as radioligand for serotonin receptor 5-$HT_{1A}$. The object of this study was to obtain the mefway precursor with the higher yield than previous method and to identify whether $^{18}F$-mefway can bind to 5-$HT_{1A}$ or not. from microPET imaging of small animal brain. Precursor was prepared by a modification of the reported procedure then [$^{18}F$] labeling was performed by adding $^{18}F$ ion at $130^{\circ}C$ in the hot cell for 30min. After purification of reaction mixture using alumina Sep-pak and HPLC, microPET images of small animal brain were determined. The chemical yield of precursor was increased from 9% to 34% using oxalyl chloride and LAH/diethylether. We synthesized a precursor which was successfully labeled with no-carrier-added $^{18}F$-by new synthetic route. This research suggest that $^{18}F$-mefway will be used a radiopharmaceutical for evaluation of central nerve system disorder as imaging a gent for 5-$HT_{1A}$ receptor.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.96-96
• /
• 2016

Nanotechnology mostly employs nano-materials and nano-structures with distinctive properties based on their size, structure, and composition. It is quite difficult to produce nano-materials and nano-structures with identical sizes, structures, and compositions in large quantities, because of spatiotemporal fluctuation of production processes. In other words, fluctuation is the bottleneck in nanotechnology. We propose three strategies to suppress such fluctuations: employing 1) difference between linear and nonlinear phenomena, 2) difference in time constants, and 3) nucleation as a bottleneck phenomenon. We are also developing nano- and micro-scale guided assembly using plasmas as a plasma nanofabrication.1-5) We manipulate nano- and micro-objects using electrostatic, electromagnetic, ion drag, neutral drag, and optical forces. The accuracy of positioning the objects depends on fluctuation of position and energy of an object in plasmas. Here we evaluate such fluctuations and discuss the mechanism behind them. We conducted in-situ evaluation of local plasma potential fluctuation using tracking analysis of fine particles (=objects) in plasmas. Experiments were carried out with a radio frequency low-pressure plasma reactor, where we set two quartz windows at the top and bottom of the reactor. Ar plasmas were generated at 200 Pa by applying 13.56MHz, 450V peak-to-peak voltage. The injected fine particles were monodisperse methyl methacrylate-polymer spheres of $10{\mu}m$ in diameter. Fine particles were injected into the reactor and were suspended around the plasma/sheath boundary near the powered electrode. We observed binary collision of fine particles with a high-speed camera. The frame rate was 1000-10000 fps. Time evolution of their distance from the center of mass was measured by tracking analysis of the two particles. Kinetic energy during the collision was obtained from the result. Potential energy formed between the two particles was deduced by assuming the potential energy plus the kinetic energy is constant. The interaction potential is fluctuated during the collision. Maximum amplitude of the fluctuation is 25eV, and the average is 8eV. The fluctuation can be caused by neutral molecule collisions, ion collisions, and fluctuation of electrostatic force. Among theses possible causes, fluctuation of electrostatic force may be main one, because the fine particle has a large negative charge of -17000e and the corresponding electrostatic force is large compared to other forces.

• The Journal of Korean Academy of Prosthodontics
• /
• v.22 no.1
• /
• pp.95-108
• /
• 1984

Even though the tarnishing and corrosion problems characteristic with dental silver-palladium alloy are not yet fully solved, it is recently widely used because of its low cost. However the effects of major alloying elements on the various properties of this system are not fully understood. The object of this research is to clarify the effects of In and Zn additives on the corrosion and tarnishing resistances and precipitation hardening behavior of this sytem, using electrodynamic polarization, immersion, and Vicker's microhardness test and X-ray diffraction and electron probe micro analysis methods. The obtained results were as follows: I. As indium content is increased, both the corrosion resistance in Cl-solution and microhardness are also increased while the tarnishing resistance is decreased. 2. As Zinc content is increased, the corrosion resistance is decreased, but tarnishing resistance is increased 3. At 70Ag-25Pd-2.5Zn-2.5In composition, the precipitation harding behavior was mot significant. The optimum aging temperature was $450^{\circ}C$ and the time was 2 hrs. The resulting specimen of this work carried 180VHN. 4. Under the heat treatment, the changes in the mechanical property are due to the changes in the shape and composition of dendrite matrix, namely, it is because of the precipitation hardening behavior which has been proved by electron probe micro analysis and optical microscopic finding.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.5
• /
• pp.1207-1212
• /
• 2015

In this paper, we propose three-dimensional (3D) visualization and recognition techniques of micro-objects under photon-starved conditions using photon counting integral imaging microscopy. To capture high resolution 2D images with different perspectives in the proposed method, we use Synthetic Aperture Integral Imaging (SAII). Poisson distribution which is mathematical model of photon counting imaging system is used to extract photons from the images. To estimate 3D images with 2D photon counting images, the statistical estimation is used. Therefore, 3D images can be obtained and visualized without any damage under photon-starved conditions. In addition, 3D object recognition can be implemented using nonlinear correlation filters. To prove the usefulness of our technique, we implemented the optical experiment.