• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.22 no.10
• /
• pp.990-998
• /
• 2011

In this paper, we have designed a multi-band single layer microstrip patch antenna with slots for GPS L2/L1, GLONASS receivers. The antenna has dual feed structure and consists of single layer microstrip patch with slots and impedance matching circuit. The antenna specifications are a VSWR(Voltage Standing Wave Ratio) of less than 2.0, RHCP(Right-Hand Circular Polarization) characteristics over the operating frequency bands of GPS L2(1,227.6 MHz)/L1(1,575.42 MHz) and GLONASS(1,602 MHz), the maximum active antenna gain of more than 30 dB and the axial ratio of less than 3 dB. The antenna has been successfully evaluated by various tests.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.40 no.5
• /
• pp.509-520
• /
• 2020

Currently, the criteria for input motions used in dam seismic design are clearly presented in general provisions of seismic design (KDS 17 10 00), and seismic ground motion records should be matched to the standard design response spectrum. However, the effect on the results is not assessed according to the selection of the seismic ground motion records, making it difficult to select seismic input motions. Therefore, in this study, the change in the amount of crest settlement of an embankment dam was assessed through numerical analysis after matching the seismic ground motion records of domestic and overseas earthquakes in accordance with the standard design response spectrum provided in the seismic design code (KDS 17 10 00). The results showed that the behavior of the upper part of the embankment, such as maximum acceleration at the crest and amplification through the dam, rather than the effect of free-field acceleration, had a greater effect on the amount of crest settlement. Moreover, it was confirmed that even an input seismic motion matched to the standard design response spectrum can make a difference in settlement depending on the characteristics of amplification through a dam body.

• 한국신재생에너지학회:학술대회논문집
• /
• 2005.06a
• /
• pp.59-63
• /
• 2005

The 800-kW PM (permanent magnet) synchronous generator is developed as a wind power generator. The matching converter is designed to control the torque and power depending on the wind speed regime. The generator starts to generate the power at the speed of 9 rpm and the rated output is generated at the speed of 25 rpm. The rated output power of an inverter is 750 kW when the PM synchronous generator is delivering 800 kW to the inverter. The inverter is specially designed to perform the maximum power point tracking (MPPT) at the low wind speed regime that is typical wind environment in Korea. The inverter test was done with a 2 MW M-G system at KERI (Korea Electric Research Institute). The M-G set has a 2 MW motor driver and a 38:1 gear to match the speed between the motor and the PM generator. The torque simulating the wind is applied to the PM generator by a DC motor. The test results show the inverter efficiency of $94.3\%$ at the rated power generating condition. The measured values show that the MPPT algorithm is working well. Overall reliability will be verified through the long-term site test.

• Journal of the Korean Wood Science and Technology
• /
• v.18 no.2
• /
• pp.49-66
• /
• 1990

In order to identify an unknown wood sample native to Korea. the softwood databases(KSWCHUN; Korean SoftWood CHUN) and the hardwood databases(KHWCHUN; Korean HardWood CHUN) had been built. and the new computer searching programs(IDINEX; IDentification INformation EXpress) has been written in Turbo Pascal(V.5.0) and in Macro Assembly(V.5.0). The characters of the data were based on the 74 features of softwood and on the 148 features of hardwood which are a part of new "IAWA list of microscopic features for hardwood identification" published in 1989. For the purpose of this investigation the wood anatomical nature of 25 species of softwood(13 genera of 5 families) and of 112 species of hardwood(57 genera of 31 families) were observed under a scanning electron microscope and light microscope. and a lot of literature used. The IDINEX programs are based on edge-punched card keys. with several improvements. The maximum number of features in the IDINEX is 229. but that is fixed for a given database. Large numbers of taxa are handled efficiently and new taxa easily added. A search may be based on sequence numbers of features. Comparisons are made sequentially by feature and taxon using the entire suite of features specified to produce the list of possible matching taxa. The results are followings. (1) The databases of Korean wood and the searching programs(IDINEX) had been built. (2) The databases of Korean wood could be an information to search an unknown wood. (3) The databases would be valuable. for the new features, which were not mentioned in Korean wood up to the present. were observed in details. (4) The ultrastructures of the cell walls(warty layer) and crystals observed under a scanning electron microscope will be helpful to search an unknown wood in particular. (5) The searching process is more quick and accurate than the others. 6) We can obtain the information on the differences of a species from the other and search an unknown wood using probability. in IDINEX, (7) The IDINEX will be utilized to identify and classify an animal life, vegetable world, mineral kingdom, and so on.

• 한국HCI학회:학술대회논문집
• /
• 2009.02a
• /
• pp.186-192
• /
• 2009

In this paper, we represent the recognition method for human frontal upper body pose. In HCI(Human Computer Interaction) and HRI(Human Robot Interaction) when a interaction is established the human has usually frontal direction to the robot or computer and use hand gestures then we decide to focus on human frontal upper-body pose, The two main difficulties are firstly human pose is consist of many parts which cause high DOF(Degree Of Freedom) then the modeling of human pose is difficult. Secondly the matching between image features and modeling information is difficult. Then using Pictorial Model we model the human main poses which are mainly took the space of frontal upper-body poses and we recognize the main poses by making main pose database. using determined main pose we used the model parameters for particle filter which predicts the posterior distribution for pose parameters and can determine more specific pose by updating model parameters from the particle having the maximum likelihood. Therefore based on recognizing main poses and tracking the specific pose we recognize the human frontal upper body poses.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.15 no.3
• /
• pp.77-81
• /
• 2009

There has been an increasing demand on measurement of the vibration levels in commercial truck shipments, where all packaged products are exposed to some levels of random vibration and shock. In this study, bear glass bottles loaded at the front, middle, and rear positions of 11 tonne truck bed was shipped from Kwangju to Waegouan. Vertical direction vibration levels were analysed and matching laboratory random vibration test was performed using power spectral density (PSD) profiles derived from truck transit records. Also, the effects of drop hight on glass bottles were evaluated. As expected, the maximum vibration levels were recorded at the rear of truck bed. No breakage of bottles were observed during truck transit and laboratory random vibration testing set at 0.52 $G_{rms}$. In drop test, glass bottles were not damaged by bottom side impact, while short side drop impact caused about twice higher bottle breakage rate than that of long side drop impact at 30 cm and 40 cm drop hight.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.5
• /
• pp.874-879
• /
• 2016

A wideband stacked patch antenna with parasitic elements, rectangular and triangle shaped patches, is proposed. Two different shaped parasitic elements are placed in the above of main rectangular microstrip patch antenna in order to achieve wide bandwidth for 860 MHz band. Coupling between the main patch and parasitic patches is realized by thick air gap. The gap and locations of parasitic patches are found to be the main factor of the wideband impedance matching. The proposed antenna is designed and fabricated on a ground plane with small size of $119mm{\times}109mm$ for application of compact transceivers. The fabricated antenna on an FR4 substrate shows that the minimum measured return loss is below -11.68dB at 824 MHz and an impedance band of 818~919 MHz(11.7%) at 10dB return loss level. The measured radiation patterns are similar to those of a conventional patch antenna with maximum gain of 2.11 dBi at 824 MHz.

• The KIPS Transactions:PartC
• /
• v.11C no.2
• /
• pp.157-162
• /
• 2004

Recently, the growth of information infrastructure is getting fatter and faster. At the same time, the security accidents are increasing together. We have problem that do not handle traffic because we have the Intrusion Detection Systems in low speed environment. In order to overcome this, we need effective security analysis techniques that ran Processed data of high-capacity because high speed network environment. In this paper we proposed the Gigabit Intrusion Detection System for coordinated security function such as intrusion detection, response on the high speed network. We suggested the detection mechanism in high speed network environment that have pattern matching function based packet header and based packet data that is proceeded in system kernel area, we are shown that this mechanism was excellent until maximum 20 times than existing system in traffic processing performance.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.05a
• /
• pp.61-62
• /
• 2018

In this paper, we studied a wideband double-sided dipole antenna operating at 3.5 GHz (WiMAX) band. The each printed dipoles are placed on the both sides of the substrate. It can be easily implemented and is suitable for connection with an active circuit. In order to obtain wideband printed dipole characteristics, thick rectangular shaped dipole is adopted. Feeding Circuit for dipole array and balun were designed for impedance matching with a $50{\Omega}$ microstrip feed line. The antenna is designed by simulation for an operation in the frequency range of 3.4~3.7 GHz Simulation results show that the maximum gain in the 3.5 GHz band is 5.5 dBi and the bandwidth with VSWR less than 2 is about 1 GHz.

• Journal of the Korea Convergence Society
• /
• v.8 no.11
• /
• pp.77-83
• /
• 2017

For efficient predictive analysis, self-healing research is needed that enables the system to recover autonomously by self-cognition and diagnosing system problems. However, software development does not provide formal contextual information analysis and appropriate presentation structure according to external situation. In this paper, we propose a prediction analysis method based on the change contents by applying the extraction rule to the functions that can act, data, and transaction based on the new Goal-scenario. We also evaluated how well the predictive analysis met through the performance indicators for achieving the requirements goal. Compared with the existing methods, the proposed method has a maximum 32.8% higher matching result through performance measurement, resulting in a 28.9% error rate and a 45.8% reduction in the change code. This shows that it can be processed into a serviceable form through rules, and it shows that performance can be expanded through predictive analysis of changes.