• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.7
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• pp.606-612
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• 2015

This paper proposes a new design of a dual-band orthogonal-polarization microstrip antenna for V2N(Vehicle to Nomadic Device) communication system. The proposed antenna consists of a perpendicular feeding structure for utilizing orthogonal linear polarizations and an microstrip radiator which loaded by close-looped H-shape slot for obtaining dual-band operation. Due to the geometrically different loading effect of the close-looped H-shape slot for each feeding location, the orthogonally linear polarization at dual-band operation of the proposed antenna can be successfully achieved. The proposed antenna theoretically and experimentally demonstrates the vertical linear polarization at the operating frequency of 1.8 GHz and the horizontal linear polarization at the operating frequency of 2.4 GHz, respectively. The simulation and measurement results of the implemented antenna have been in good agreement with the reflection coefficients, radiation patterns, and realized antenna gains.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.4A
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• pp.324-329
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• 2009

In this paper, a novel Snowflake-shaped microstrip patch antenna for application in the WLAN(5.2/5.8GHz) band is designed and fabricated. The size of antenna is $21.2{\times}16mm^2$ and substrate is used Taconic-RF30. To obtain sufficient bandwidth in Return loss <-10dB and dual resonance characteristic, the Short-pin is inserted on the patch and the coaxial probe source is used. The measured results of fabricated antenna show 220MHz and 135MHz bandwidth in Return loss <-10dB referenced to the WLAN(5.2/5.8GHz) band. The measured antenna gain is $4.7{\sim}6.9dBi$ in the WLAN(5.2/5.8GHz) band. The experimental 3-dB beam width in I-plane and H-plane are $73.2^{\circ}/82.75^{\circ}$ for 5.1500Hz, $74.56^{\circ}/83.63^{\circ}$ for 5.3500Hz, and $86.24^{\circ}/85.15^{\circ}$ for 5.7850Hz, respectively.

• Journal of Life Science
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• v.17 no.12
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• pp.1669-1674
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• 2007

The conventional histochemical stains were used to study the properties of mucosubstances of the intestine in four teleostean species, i. e., Agramus agramus, Inimicus japonicus, Epinephelus chlorostigma, and Helicolenus dactylopterus, all belonging to the order Perciformes. The following methods were used; periodic acid Schiff (PAS), alcian blue (AB) pH at 2.5, AB pH at 1.0, AB pH at 2.5-PAS, and aldehyde fuchsin (AF) pH at 1.7-AB pH at 2.5 stain. The mucosal folds of intestines show differences in species and regions. Widely distributed in all portions studied, goblet cells situated between cylinderical epithelial cells are round or ovoid in shape. They were most densely distributed in distal intestine. In the middle and. distal intestine of Epinephelus chlorostigma and all regions of intestines of Agramus agramus, Inimicus japonicus, and Helicolenus dactylopterus, the presence of both acidic and neutral mucin was confirmed. The property of acidic mucosubstance was sialomucin. Neutral mucin was only encountered in the proximal intestine of Epinephelus chlorostigma. The amount and property of mucin showed differences in species and regions. In the distal intestine of Inimicus japonicus, the amount of acidic mucin is similar to that of neutral mucin. In all regions of intestine of Agramus agramus, proximal and middle intestine of lnimicus japonicus, middle and distal intestine of Epinephelus chlorostigma, and distal intestine of Helicolenus dactylopterus, acidic mucin occured more frequently than neutral mucin. The proximal and middle intestine of Helicolenus dactylopterus have more neutral mucin than acidic mucin.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.625-628
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• 2003

In this paper, a wideband two-layer H-shaped microstrip antenna for WLAN is designed and studied experimentally. To increase the bandwidth of microstrip patch antenna, a configuration of stacked type using parastic element is used, Furthermore, to reduce the size of microstrip patch antenna, the first technique is H-shaped patch type. the second technique is that the main radiator and parastic patch are shorted to the ground plane using ten shorting posts. The antenna bandwidth and radiation characteristics are calculated by ENSEMBLE ver. 5.0 simulation software, and compared with the experimental results, Experimental results show that the return loss is less than -10dB over the band of 5.086GHz to 5.832GHz, which is quite good agreement with the calculations.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.147-149
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• 2011

사용자에게 편리한 인터페이스를 제공하는 IT 기기가 널리 보급되면서 직관적인 인터페이스 기술에 대한 관심이 높아지고 있다. 이미지 센서로 입력된 사람의 손 모양이나 움직임을 이용하는 인터페이스가 그 중 하나이다. 한 편 이미지 센서 영상을 저장하기 위하여 H.264/AVC와 같은 영상 압축 기술이 사용된다. 영상을 압축하기 위해 부호기는 모든 Macroblock에서 움직임 추정을 수행한다. 추정된 움직임 정보는 손 움직임을 인식하는데 사용될 수 있고 이를 통해 전자 기기에 명령을 내리는 인터페이스 기술의 한 부분을 구현하는 것이 가능하다. 본 논문은 H.264/AVC 부호기의 Motion Vector를 이용하는 손 추적 알고리즘을 제시한다. 제시된 알고리즘은 손 움직임 추적의 정확도를 향상시키기 위하여 Motion Vector보다 신뢰도가 높은 Motion Density Map 정보를 사용한다. 이 정보를 이용하여 이동한 손을 포함하는 손 윈도우를 결정한다. 실험 결과를 통하여 제시된 알고리즘이 손의 움직임을 추적하는 것을 확인할 수 있다.

• Membrane Journal
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• v.20 no.2
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• pp.169-172
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• 2010

Silver ions of poly(vinyl chloride)-g-poly(styrene sulfonic acid) (PVC-g-PSSA) graft copolymer were reduced to form silver nanoparticles under thermal condition ($80^{\circ}C$). We were successful in synthesizing silver nanoparticles with various morphologies by changing reaction time. At short reaction times (~1 h), silver nanoparticles with 5 nm in size were formed without disrupting a microphase-separated structure of graft copolymer. At medium reaction times (~5 h), silver nanoparticles were aggregated to form large clusters ranging 30~50 nm in size. At much longer reaction times (~18 h), hurricane-like silver clusters were observed due to strong particle aggregation.

• Korean Journal of Materials Research
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• v.11 no.1
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• pp.61-66
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• 2001

$TiO_2$films for photocatalytic reaction were synthesized by anodizing process. The photocatalytic efficiencies of anodized $TiO_2$were evaluated by the rate of decomposition of aniline blue. The properties of photocatalysis on anodic $TiO_2$films have been observed, but the efficiencies of photocatalytic reaction depended on the conditions of films formation. The microstructure of the anodic film formed in $H_2SO_4$ solution differed from that of $TiO_2$films formed in $H_2SO_4+H_3PO_4$ solution. It has been shown that the appropriate applied-voltage for anodizing of titanium for photocatalysis was 180V in both aqueous solutions.

• Journal of Radiation Protection and Research
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• v.34 no.2
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• pp.69-75
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• 2009

To obtain precise information about characteristics of gamma ray detector system responses, we developed new GUI computer program to analize full-energy absorption peak using our developed Delphi computer code for educational purpose. By use of the well known 4 nonlinear peak shaping functions, peaks were fitted with least square fit method in this code. In this paper, we described the methods to search for 12 coefficients in above 4 nonlinear peak shaping functions by use of our developed code in details. The computer code was tested for 1 $\mu$Ci $^{137)Cs$ 661 keV gamma ray peak spectrum detected by 25 % relative efficiency HPGe detector with 5.35 cm (D) $\times$ 5.5 cm (L) size.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.538-538
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• 2008

금속계열의 박막을 평탄화하기위해서는 슬러리에 함유된 산화제에 의해 부동태층의 형성이 선행되어야 한다. 따라서 본 논문에서는 Copper 박막의 표면을 부동태층으로 형성시키고 CMP공정을 하기위해 산화제에 dipping을 시켰으며 삼화제의 종류는 $H_2O_2$, MSW2000B, $KIO_3$로 하고 dipping 시간은 30초, 60초, 90초, 3분, 10분으로 하여 시간과 산화제 종류에 따른 부동태층의 변화를 연구하였다. 부동태층의 관찰은 FESEM을 이용하여 표면과 단면을 관찰하였고 부동태층의 조성비율은 EDX를 이용하여 조사하였다. MSW 2000B의 경우는 부동태층이 덩어리 모양으로 형성되었으며 포화현상은 3분에 일어났다. 반면에 $H_2O_2$의 경우는 부동태층이 침상 모양으로 형성되었으며 포화현상은 90초에 일어났다. 산화제에 의해 부동태층을 형성시킨 후 POLI-450을 이용하여 평탄화공정을 진행하였으며 CMP공정조건은 부동태층의 연질상태임을 감안하여 헤드 스피드 20rpm, 플레이튼 스피드 10rpm, 슬러리 주입속도 90ml/min, 공정온도는 상온으로 하여 진행하였다. $H_2O_2$를 산화제로 사용하여 dipping을 하고 CMP를 하였을 경우에 균일한 박막을 확보 할 수 있었으며 CMP 공정 후 copper 박막의 균일성은 FESEM을 이용하여 관찰 하였다.

• Journal of the Korean Magnetics Society
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• v.3 no.1
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• pp.13-17
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• 1993

We have studied $CuF_{2}.2H_{2}O$ using $^{1}H$ and $^{19}F$ pulsed nuclear magnetic resonance at 30 MHz. From the data of lineshapes, the spin-lattice relaxation times ($T_1$) and the spin echo decay times, lattice dynamics in the structure is investigated. $T_1$ data from both $^{1}H$ and $^{19}F$ NMR indicate that spin-lattice relaxation is dominated by the paramagnetic ion centers at the Cu sites. The lineshapes at room temperature appear to be strongly affected by exchange narrowing and motional narrowing.