• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.16 no.10
• /
• pp.887-891
• /
• 2003

In this paper, two filters with center frequency of 19.58MHz were cascaded and its bandwidth characteristics were investigated with the variations of coupling capacitance for intermediate frequency (IF) bandpass filter application. The cascaded filter showed the higher stop region, reduction of spurious response and increase of selectivity. With the increase of coupling capacitance, insertion loss was increased but spurious response reduced. The cascaded filter with coupling capacitance of 15pF showed insertion loss of 5.643dB, 3dB bandwidth of 55.089kHz and 20dB bandwidth of 83.608kHz, respectively.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.306-306
• /
• 2000

This paper analyze the dynamic characteristics of Automated Guided Vehicle(AGV) which is being developed as a part of automation in port through DADS, one of the multi-dynamic analysis program, Previous evaluation of a vehicle is carried out through the continuous driving test of a real vehicle, however this method raise the loss of finance and time. If it is possible to analyze the dynamic characteristics of vehicle before construction completely we can compensate the loss of money and time during constructing. AGV contained containers is very heavy and its center of gravity can be easily changed with the disturbance from road or cornering. It makes AGV unsatisfied, therefore we evaluate the handling characteristics and stability of the full vehicle model. This paper contribute to establish the foundation of the development of a new system like a AGV which have a special structure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.1234-1237
• /
• 2002

When measuring sound transmission loss (STL) in a laboratory, the specimen location in test aperture affects considerably the measuring accuracy through the influence of so-called “tunneling effect” In this paper, for a single panel and a double panel with air cavity, experimental STL evaluations on various specimen locations on test aperture were carried out to explain the phenomenon. It is shown that the difference of STL is more than 2dB especially at the low frequency region and the case of the center-located panel yielded the lower STL than that of flushing with the end of tunnel, which confirms that the tunneling effect plays an important role in STL measurement.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.9 no.2
• /
• pp.129-138
• /
• 2006

Lots of cases relating Helicobacter pylori infection to iron-deficiency anemia have been described in the literature and H. pylori infection has emerged as a cause of refractory iron-deficiency anemia which is unresponsive to oral iron therapy. H. pylori-associated iron-deficiency anemia can be treated by H. pylori eradication. It is not thought to be attributable to gastrointestinal blood loss, such as duodenal ulcer. The mechanism by which H. pylori infection contributes to iron-deficiency anemia remains unclear. However, four possible explanations can be posited for this relationship; occult blood loss secondary to chronic gastritis, reduced iron absorption due to hypo- or achlorhydria, increased iron consumption by H. pylori, and iron sequestration in gastric mucosa. H. pylori-associated iron-deficiency anemia seems to develop in populations at increased risk for iron depletion. When pubescent girls, including athletes, are found to have iron-deficiency anemia refractory to iron administration, they should be evaluated for H. pylori infection.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.11 no.1
• /
• pp.76-83
• /
• 2000

A 2-pole tunable bandpass filter was design and fabricated using ceramic coaxial resonators and varactor diodes for UHF band. By inspection of frequency characteristics of the T-and $\pi$-type inverter equivalent circuits, we can design a two-pole tunable BPF with only two varactors. The measured data of the filter show 800 MHz-900 MHz tunable center frequency range, 4.5 dB insertion loss, 0.5 dB passband ripple and at least 15 dB return loss, which agree well with the simulated results.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.1555-1558
• /
• 2008

In this paper, result of whole test, When the Transfer Distance is increasing, Strength of Backfilling Material of NATM Composite lining Tunnel due to increasing Gravity was increased, but that is higher the Air Flotation than increasing Strength. So, That was predicted a drop of Permeability. And Performing the placing Lightweight Foamed Mortar, we think that it's performance in drain material was lost. Therefore We conclude that Proper Transfer Distance that taking Permeability through minimizing of Air Flotation Loss and getting the Need Strength is 50m.

• IE interfaces
• /
• v.16 no.spc
• /
• pp.39-44
• /
• 2003

As one of many design variables, the role of dimension tolerances is to restrict the amount of size variation in a manufactured feature while ensuring functionality. In this study, a nonlinear integer model has been modeled to allocate the optimal tolerance to each individual feature at a minimum manufacturing cost. While a normal distribution determines statistically worst tolerances with its symmetrical property in many previous tolerance allocation studies, a asymmetrical distribution is more realistic because its mean is not always coincident with a process center. A nonlinear integer model is modeled to allocate the optimal tolerance to a feature based on a beta distribution at a minimum total cost. The total cost as a function of tolerances is defined by machining cost and quality loss. After the convexity of manufacturing cost is checked by the Hessian matrix, the model is solved by the Complex Method. Finally, a numerical example is presented demonstrating successful model implementation for a nonlinear design case.

• Journal of the Korea Society of Computer and Information
• /
• v.21 no.12
• /
• pp.27-33
• /
• 2016

In this paper, we propose the bilateral filter based on median value that can reduce random noise and impulse noise with minimal loss of contour information. In general, EO / IR camera to generate a random or impulse noise due to a number of reasons. This noise reduces the performance of detecting and tracking by signal processing. To reduce noise, our proposed bilateral filter sorts the values of the target pixel and the peripheral pixels, and extracts a median filter coefficients of the Gaussian type. Then to extract the Gaussian filter coefficient involved with the distance between the center pixel and the surrounding pixels. As using those filter coefficients, our proposed method can remove the various noise effectively while minimizing the loss of the contour information. To validate our proposed method, we present experimental results for several IR images.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.22 no.6
• /
• pp.97-102
• /
• 1985

A new microwave transmission line frequency discriminator in MIC is described, which is composed of a branch-line hybrid 3dB coupler, a λ/2-short stub and a λ/4-opcn stub. It is experimentally verified that the discriminator is linear in a 400 MHz bandwidth at center frequency 4.94 GHz and has return loss more than 15dB in that range.

• Proceedings of the IEEK Conference
• /
• 2007.07a
• /
• pp.255-256
• /
• 2007

We propose a frame loss concealment algorithm for multi-view video sequences based on correspondence matching, which can hide the effects of frame losses efficiently. To achieve high PSNR performances, we employ a block error concealment scheme to refine the concealed results. Simulation results demonstrate that the proposed algorithm effectively protects the quality of reconstructed videos against transmission errors.