• Korean Journal of Optics and Photonics
• /
• v.10 no.5
• /
• pp.424-429
• /
• 1999

The amplifier properties of single distributed feedback dye laser with 106 ps pulse width and 616 nm wavelength were invested using only one XeCl-excimer laser as pump source. For optimized amplification of DFDL, the three-stage amplifiers were arranged with increasing cross-section and accordingly increasing pump energies. The first AmpI, II stages were dye cell of 5 mm, 10 mm and contained a $6{\times}10^{-4}$ [mol/l](solvent : Methanol) of Rhodamine 610. Double-pass amplification in the AmPII was measured to suppress the ASE by using a diffraction grating. The beam intensity of AmpI, II was saturated with a gain of respectively 10 and 48. The last AmpIII was Bethune cell of 30 mm and contained a $3{\times}10^ {-4}$ [mol/l] (solvent : Ethanol) of Rhodamine 610. In the single-pass and double-pass amplification, the output energy was obtained 168.2 $\mu$J and 471$\mu$J respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.10
• /
• pp.851-857
• /
• 2014

This paper addresses the design of the auto race-track and figure-8 flight mode which can be applied to expand the loitering flight mode and increase the safety of UAV. To implement these flight modes, necessary waypoints and entry points can be calculated automatically from several information of the ground control system. The flight logic is proposed to pass the desired waypoints as well as entry points and transfer to the desired flight path by combining the light-of-sight and loitering guidance controller. The proposed algorithm and logic is verified using the 6-DOF UAV model and nonlinear simulation under the several flight conditions.

• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.12
• /
• pp.1167-1175
• /
• 2010

This paper presents the use of the inertial measurement unit information and the infrared sector information for getting the position of an object. Travel distance is usually calculated from the double integration of the accelerometer output with respect to time; however, the accumulated errors due to the drift are inevitable. The orientation change of the accelerometer also causes error because the gravity is added to the measured acceleration. Unless three axis orientations are completely identified, the accelerometer alone does not provide correct acceleration for estimating the travel distance. We propose a way of minimizing the error due to the change of the orientation. In order to reduce the accumulated error, the infrared sector information is fused with the inertial measurement unit information. Infrared sector information has highly deterministic characteristics, different from RFID. By putting several infrared emitters on the ceiling, the floor is divided into many different sectors and each sector is set to have a unique identification. Infrared light based sector information tells the sector the object is in, but the size of the uncertainty is too large if only the sector information is used. This paper presents an algorithm which combines both the inertial measurement unit information and the sector information so that the size of the uncertainty becomes smaller. It also introduces a framework which can be used with other types of the artificial landmarks. The characteristics of the developed infrared light based sector and the proposed algorithm are verified from the experiments.

• The Journal of Society for e-Business Studies
• /
• v.17 no.3
• /
• pp.1-14
• /
• 2012

As the techniques of electronic and information are advancing, the computing power of a smart phone is becoming more powerful and the storage capacity of a smart phone is becoming larger. As the result, various new useful services are becoming available on smart phones. The context-aware service and mobile augmented reality have recently been the most popular research topics. For those newly developed services, identifying the object in the picture taken by the camera on the phone performs an extremely important role. So, many researches of identifying pictures have been published and most of them are based on the time consuming image recognition techniques. On the contrary, this paper introduces a very fast and effective method of identifying the objects on the photo making use of the sensor data obtained from the smart phone and electronic maps. Our method estimates the line of sight of the camera with the location and orientation information provided by the smart phone. Then it finds any element of the map which intersects the line of sight. By investigating those intersecting elements, our method identifies the objects on the photo.

• The Journal of Society for e-Business Studies
• /
• v.14 no.2
• /
• pp.117-130
• /
• 2009

Lots of applications that represent and utilize geographic information on the Web have emerged on the Web. In addition, personal electronic devices equipped with GPS function, which can record personal location information in real time, are being increasingly adopted by people. Such geographic information enables Internet business companies to provide users more useful services based on the location information. Most successful Internet business companies have adopted and utilized Web 2.0 technologies, which promote users' participation and emphasize openness and information sharing. Especially, using open APIs (Application Programming Interfaces) can reduce the costs of a program development. In this study, we design and develop a banner advertisement system based on geographic information using open APIs. We propose a business model using the advertisement system, and a prototype system has been illustrated in order to explain the proposed business model. Finally, we summarize the benefits of our system by describing factors generating values of the proposed business model. Hopefully, main ideas proposed in this paper can be applied to real industry sectors that use geographic information widely such as travel, real estate and so on.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.24 no.6
• /
• pp.242-245
• /
• 2014

In order to increase the thickness uniformity in chemical vapor depositon of silicon carbide, we have carried out CFD studies for a CVD apparatus having a horizontally-rotated 3-stage susceptor. We deposited silicon carbide films of 3C-SiC phase showing quite uniform thickness between stages but not uniform one in the stage. The cause of this nonuniformity is thought to be originated from the high rotational speed. And the uniformity between stages can be further increased with the $120^{\circ}$ split type nozzles from CFD results. Through the formation of silicon carbide film on graphite substrates we can make oxidation-resistant and dust-free graphite components with high hardness for the semiconductor applications.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.1
• /
• pp.193-202
• /
• 2012

RFID tag awareness information and sensor data continuously change, and are categorized with the position. They are able to similar data in the side, called massive data to change in time. If two data are managed together, a convergence process of object awareness along change of environment is possible. If RFID middleware and EPCIS repository realized the integrated system, it is usable with the functions of middleware and repository at the same time. The real-time awareness information retrieval is possible without process, getting information from another middleware. In this paper, it is able to continuously read information from RFID reader and sensor equipment and store to database in order to make general object awareness and an object retrieval dependent on an environmental information change possible by real time. ALE-compliant middleware and EPCIS repository proposing for standards at EPCglobal is designed and implemented to be able to deal with RFID and sensor data to bases on the collected data.

• Journal of Digital Convergence
• /
• v.16 no.3
• /
• pp.303-309
• /
• 2018

Computer vision technology is a component inspection to obtain a video image from the camera to the machine to perform the capabilities of the human eye with a field of artificial intelligence, and then analyzed by the algorithm to determine to determine the good and bad of production parts It is widely applied. Shape inspection method was used as how to identify the location of the start point and the end point of the search range, measure the height to the line scan method, in such a manner as to determine the presence or absence of the bolt tabs average brightness of the inspection area in a circular scan type value And the degree of similarity was calculated. The total time it takes to test in the test performance tests of two types of bolts tab enables test 300 min, and demonstrated the accuracy and efficiency of the inspection on the production line represented a complete inspection accuracy.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.27 no.5
• /
• pp.353-360
• /
• 2014

The model ice is created at KRISO (Korea Research Institute for Ships and Ocean Engineering) ice basin where model ship is tested to obtain the necessary data in order to design the ice breaking vessels and ocean structures operating in the northern pole sea area. Through the model ship test, ice breaking, clearing, ice-ship and ice-propeller interaction behavior can be obtained. Since mechanical properties of ice plate are required for the model test, some tests are performed to obtain the properties in this paper. First, ultrasonic devide is used to measure the thickness of the model ice plate and the results show the possibility of using ultrasonic method, yet more sophisticated device or special sensors are required to measure the ice thickness completely. And the defection of ice plate is measured using LVDT to compute the characteristic length of ice plate on the fluid, which is used to get the effective Young's modulus of model ice.

• Journal of the HCI Society of Korea
• /
• v.3 no.1
• /
• pp.1-7
• /
• 2008

Recently researchers have studied mobile physiological sensing device. However, previous works focused on multiple and real time physiological sensing method, instead of aesthetic shape of sensing devices, sensing comfort during monitoring and sensing reliability against the hand motion artifact. In this work, we propose a stone shaped physiological sensing device to monitor the physiological status in a daily life which maximize the aesthetic feeling and sensing comfort and sensing reliability. We proposed stepwise user centered design process for user centric physiological sensing device and evaluated appropriate sensing positions against the hand motion artifacts and pressure from sensors. From the usability test and experiments, we verified the proposed sensing device provides the aesthetic appeals, sensing comfort and sensing reliability. We expect that this work can be applied in the various health care applications in near future.