国内外区域旅游合作研究进展

Shanting Zheng,김영문,Lu Lin,Chen Hao,이상엽 한국비교정부학회 2008 한국비교정부학보 Vol.12 No.1

Tourism industry is very opening and interdependant, Tourism Cooperative Partnerships must be thought much of to realize the sustainability. The paper analyze the research about the Tourism Cooperative Partnerships. The form of the Tourism Cooperative Partnerships is important basic of the relation of the region or some common objective, eg, development of sustainable tourism etc. Tourism Cooperative Partnerships can bring some potential advantages for region, but it is difficult to form the relation. The research involved the processes and pattern, politics and practice, emerging approaches.

Mouse Fyn induces pseudopodium formation in Chinese hamster ovary cells

Lei An,Shengnan Liu,Wei Zhang,Yamei Zhang,Yingxue Huang,Xinde Hu,Shu-lin Chen,Shanting Zhao 대한수의학회 2014 JOURNAL OF VETERINARY SCIENCE Vol.15 No.1

Molecular mechanisms underlying the effects of Fyn on cellmorphology, pseudopodium movement, and cell migrationwere investigated. The Fyn gene was subcloned into pEGFP-N1to produce pEGFP-N1-Fyn. Chinese hamster ovary (CHO)cells were transfected with pEGFP-N1-Fyn. The expression ofFyn mRNA and proteins was monitored by reversetranscription-PCR and Western blotting. Additionally,transfected cells were stained with 4´,6-diamidino-2-phenylindole and a series of time-lapse images was taken. Sequences of the recombinant plasmids pMD18-T-Fyn andpEGFP-N1-Fyn were confirmed by sequence identificationusing National Center for Biotechnology Information in USA,and Fyn expression was detected by RT-PCR and Westernblotting. The morphology of CHO cells transfected with therecombinant vector was significantly altered. Fyn expressioninduced filopodia and lamellipodia formation. Based on theseresults, we concluded that overexpression of mouse Fyn inducesthe formation of filopodia and lamellipodia in CHO cells, andpromotes cell movement.

Coactosin-like protein 1 inhibits neuronal migration during mouse corticogenesis

Guohong Li,Yupeng Yin,Jiong Chen,Yanle Fan,Juhong Ma,Yingxue Huang,Chen Chen,Pengxiu Dai,Shulin Chen,Shanting Zhao 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.1

Coactosin-like protein 1 (Cotl1), a member of the actin-depolymerizing factor (ADF)/cofilin family, was first purified from a soluble fraction of Dictyostelium discoideum cells. Neuronal migration requires cytoskeletal remodeling and actin regulation. Although Cotl1 strongly binds to F-actin, the role of Cotl1 in neuronal migration remains undescribed. In this study, we revealed that Cotl1 overexpression impaired migration of both early- and late-born neurons during mouse corticogenesis. Moreover, Cotl1 overexpression delayed, rather than blocked, neuronal migration in late-born neurons. Cotl1 expression disturbed the morphology of migrating neurons, lengthening the leading processes. This study is the first to investigate the function of Cotl1, and the results indicate that Cotl1 is involved in the regulation of neuronal migration and morphogenesis.

Antenna Investigation by a Thermoelastic Optical Indicator Microscope: Defects Measurement and 3D Visualization of Electromagnetic Fields

Arakelyan, Shant,Lee, Hanju,Babajanyan, Arsen,Kim, Seungwan,Berthiau, Gerard,Friedman, Barry,Lee, Kiejin IEEE 2019 IEEE antennas and propagation magazine Vol.61 No.2

<P>Using the thermoelastic optical indicator microscopy (TEOIM) technique, we perform the visualization of the near-field distribution of a patterned frequencymodulation (FM) antenna. For the defect characterization, subtraction of images is done, whereas a background image is used for the defect-free antenna image. The electromagnetic fields distribution in the overall antenna structure is changed due to the defects, and this indicates the local impedance changes of the antenna pattern. The sensitivity of the proposed inspection technique is estimated to be in orders of a few milliwatts. In addition, a 3D visualization of the antenna transmission is realized to describe the field intensity and distribution dependences on the distance from the antenna surface. This type of investigation with a visualization opportunity may become an important tool for engineers and researchers, and it can successfully be a supplement for existing measurement techniques.</P>

자기광학 효과를 이용한 도선의 자기장 분포 영상화

전성훈,Shant ARAKELYAN1,이연섭,김용재,한혜지,장현욱,정영훈,이한주,이기진,차덕준 한국물리학회 2016 새물리 Vol.66 No.2

We studied the visualization of the magnetic field distribution on patterned current wires (DC) by using the magneto-optical (MO) imaging method with a Bi:YIG sensor film produced by metal organic decomposition (MOD). The Bi:YIG thin film was produced by spin coating, drying and pre-annealing after a Bi$_1$Y$_2$Fe$_5$O$_{12}$ solution had been distributed uniformly on glass . An amorphous phase of the metal-oxide thin film was obtained by using repeated spin coatings, dryings and pre-annealings. The observed detectable minimum magnetic field of the garnet sensor film was about 0.2 Gauss. To increase the quality of MO images, we used the DC voltage modulation technique instead of the polarizer modulation method. The measured magnetic field distribution on the direct wire was compared with that of simulation. 유기금속분해 방법을 통해 제작된 Bi:YIG (Bi$_1$Y$_2$Fe$_5$O$_{12}$) 자기장 센서 박막을 사용하여 패턴된 도선에 흐르는 직류전류가 만드는 자기장 분포를 MO (magneto-optic) 영상화 기법을 통해 이미징하였다. Bi:YIG 박막의 제작은 스핀코팅을 이용하여 유리기판 위에 제작하였고, Bi$_1$Y$_2$Fe$_5$O$_{12}$ 용액을 고르게 분포시킨 후 건조작업을 거친 뒤 전열처리 시켜 제작하였다. 스핀코팅, 건조작업 및 전열처리를 반복하여 비정질상의 금속 산화물 박막을 얻었다. Bi:YIG 박막을 통해 감지 할 수 있는 최소 자기장은 약 0.2 가우스였다. DC 전류가 만드는 자기장 이미지를 극대화하기 위해 MO 시스템의 편광판을 운용하는 방법을 사용하지 않고 DC전압을 변조하는 방법을 이용하여 측정하였다. 직선 도선에서 측정 된 DC에서 형성된 자기장 분포를 시뮬레이션의 결과와 비교 분석하였다.

비대칭 감쇄극을 사용한 유전체 세라믹 도파관 필터

김승완,Shant ARAKELYAN,이기진,김종철,차덕준 한국물리학회 2017 새물리 Vol.67 No.12

We studied dielectric ceramic waveguide filters using cascade trisection (CT) cross-coupled structures with an odd number of resonators between non-adjacent resonators. A dielectric ceramic waveguide (DCW) filter was designed based on the asymmetric attenuation pole in the desired frequency band. The DCW consisted of rectangular ceramic resonators with an even number of resonators between non-adjacent resonators. DCW filters satisfy the demands for selectivity, band rejections, and pass band insertion loss. For the multiple coupled resonator filters, the extraction of circuit elements with conversion to a coupling matrix was described. The designed DCW filter agreed with the simulation results. 비인접한 공진기들 사이에 홀수개의 공진기를 가지도록 하는 CT (cascade trisection) 교차 결합 구조 유전체 세라믹 필터를 제작하였다. CT 교차 결합 구조를 기반으로 원하는 주파수 대역에 비대칭 감쇄극을 형성할 수 있도록 하는 새로운 소형 유전체 세라믹 도파관 (dielectric ceramic waveguide, DCW) 필터를 제안하였다. 직사각형 공진기로 구성된 세라믹 도파관 필터는 구조상 비인접한 공진기들 사이에 짝수개를 구성하였다. 다중 결합 공진기 필터에 대해 결합 행렬로 변환한 후의 회로 요소의 추출에 기초한 합성 절차를 설명하였다. DCW 필터의 합성, 설계 그리고 시뮬레이션 결과는 제작된 필터 주파수 특성과 일치한 결과를 얻었다.

Microwave Heating Visualization for Carbon Fibers Composite Material: Development of Tunable Microstrip Structures

Arakelyan, Shant,Lee, Hanju,Han, Do-Suck,Babajanyan, Arsen,Berthiau, Gerard,Friedman, Barry,Lee, Kiejin Professional Technical Group on Microwace Theory a 2018 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>The visualization of carbon fibers polyether ether ketone (PEEK) composite material heating for a grounded coplanar waveguide and a stepped impedance low-pass filter by the thermal camera is performed. The purpose of such visualization is to characterize electromagnetic field influence on the diagonally anisotropic composite material and find out its application opportunity. COMSOL Multiphysics simulation has been done in order to understand heating principles and origin. Experimental results were in a good agreement with simulations and they showed that the characteristics of the microstrip structures can be modulated/tuned by simple rotation of the composite material. Finally, a tunable application by the carbon/PEEK composite material for the microstrip low-pass filter was developed due to the microwave absorption selectivity dependence on the composite material orientation.</P>

후열처리된 펜타센 유기박막 트랜지스터

이연섭,전성훈,Shant ARAKELYAN,정영훈,장현욱,한혜지,김용재,이한주,이기진,차덕준 한국물리학회 2016 New Physics: Sae Mulli Vol.66 No.2

In this research, we treated the pentacene OTFTs (organic thin film transistors) with post-annealing process after deposition. The thicknesses of the pentacene thin films and the post-annealing temperatures were 15 nm, 70 nm, 200 nm and RT (room temperature), 70 $^\circ$C, 100 $^\circ$C, 130 $^\circ$C, 160 $^\circ$C, respectively. The crystalline structures of the pentacene organic thin films were observed by using X-ray diffraction and atomic force microscopy. For pentacene OTFTs, we found that the traps at the pentacene thin films coexist with the bulk and that the thin-films phases prevent any improvement of the electrical properties. The mobility of the pentacene OTFT with a film thickness of 15 nm was recorded as the highest one, and the mobility of the pentancene OTFT treated at a post-annealing temperature of 70 $^\circ$C was recorded as 0.0151 cm$^{2}$/V$\cdot$s, which was the highest value for the post-annealing process. 본 논문에서는 펜타센 유기물을 고진공 상태에서 열증착 한 후 후열처리에 의한 유기물 박막의 변화를 관측하였다. SiO$_{2}$ 절연체가 200 nm 코팅된 실리콘 기판에 펜타센 박막을 0.2 $\sim$ 4 \AA$\cdot$s$^{-1}$의 속도로 15 nm, 70 nm, 200 nm 만큼씩 쌓았다. 후열처리 온도는 RT, 70 $^\circ$C, 100 $^\circ$C, 130 $^\circ$C, 160 $^\circ$C로 주었다. 펜타센 박막을 이용해서 X선 회절 (X-ray diffraction, XRD), 원자현미경 (atomic force microscopy, AFM)를 사용해 유기물 박막의 표면과 구조가 후열처리에 따라 변하는 것을 확인하였다. 유기물 박막 위에 금으로 소스 및 드레인 층을 증착하여, 펜타센 박막의 후열처리 조건에 따른 펜타센 OTFTs의 전기적 특성 변화를 관측하였다. 덩어리 상태 (bulk phase)와 박막 상태 (thin film phase)의 공존에 의해 생긴 트랩은 후열처리를 하더라도 개선하기 어렵다는 것을 확인하였다. 전하이동도만을 고려하면 두께는 15 nm에서 좋은 전하이동도를 보였고, 70 $^\circ$C로 후열처리 했을 때, 0.0151 cm$^{2}$/V$\cdot$s 로 후열처리 조건 중에서 가장 높은 전하이동도를 보였다.

메타물질을 이용한 소형 마이크로파 필터 설계

전성훈,이한주,Shant ARAKELYAN,장현욱,정영훈,한혜지,이기진,김종철,오동훈,차덕준 한국물리학회 2016 새물리 Vol.66 No.11

We prepared miniaturized microwave filters by using a metamaterial with conductor patterns with spiral shapes. Aluminum-oxide (Al$_2$O$_3$) substrates with a dielectric constant about 9.8 were used. After silk screen-printing with silver paste on the substrate, the spiral structures were patterned by using a laser patterning technique. The results for the fabricated filters were compared with the simulation data obtained using HFSS (high-frequency structural simulator). Finally, we fabricated filters that had smaller sizes and higher frequencies compared the usual CSRR (complementary split-ring resonator) filters. The areas of the fabricated microwave filters were about tens of mm$^2$. 메타물질을 이용하여 나선모양의 전도체 패턴을 이용한 소형화된 마이크로파 필터를 설계 및 제작하였다. 기판은 유전율 9.8의 산화알루미늄(Al$_2$O$_3$)을 사용하였고, 실크스크린 방법을 이용하여 기판 위에 실버 후막을 코팅한 후, 레이저 패터닝을 통하여 나선 모양의 필터 패턴을 구현하였다. 제작된 필터의 s-parameter 측정 결과는 HFSS를 이용한 simulation data와 비교하였다. 마지막으로, 제작된 나선모양 필터의 크기가 감소할수록 공진주파수가 증가하는 것을 확인하였고, 나선의 회전수가 감소할수록 공진주파수가 증가하는 것을 확인하였다. 제작된 마이크로파 필터는 패턴의 크기가 수 십 mm$^2$에 해당하는 작은 면적의 필터 소자를 제작할 수 있었다.

금속산화물 다층 구조 전극을 이용한 유기물 박막 트랜지스터의 전하 주입 특성 향상

정영훈,장현욱,한혜지,전성훈,Shant ARAKELYAN,이한주,이기진,오동훈,차덕준 한국물리학회 2017 새물리 Vol.67 No.1

We studied the effect of insertion of metal-oxide layers into electrodes for OTFTs (organic thin film transistors) to improve their electrical characteristics. The thickness of pentacene was about 50 nm and the metal electrode was made of gold. The metal-oxide thin-film layers inserted between the electrode and the organic pentacene layers were about 2$\sim$8 nm and the electrical properties of the inserted metal-oxide layers were measured by using UPS (ultraviolet photoelectron spectroscopy). From the results for the electrical properties, the mobility and the threshold voltage of the OTFTs with inserted WO$_3$ layers were improved from 8.80 $\times$ 10$^{-3}$ cm$^2$/V$\cdot$s to 2.48 $\times$ 10$^{-2}$ cm$^2$/V$\cdot$s and were decreased from -12.3 V to -4.09 V, respectively. The mobility and the threshold voltage of the OTFTs with inserted TiO$_2$ layers were decreased to 7.04 $\times$ 10$^{-3}$ cm$^2$/V$\cdot$s and -3.38 V, respectively. From the results of the UPS analysis, we found that the inserted WO$_3$ layers decreased and TiO$_2$ layers increased the energy barriers at the interface between the electrode and the organic pentacene layers. 본 연구에서는 유기물 박막 트랜지스터(organic thin film transistor, OTFT)의 전기적 특성을 향상시키기 위해서 금속산화물인 WO$_3$와 TiO$_2$ 박막을 삽입한 다층 구조 전극에 대한 연구를 수행하였다. OTFT의 활성층으로 펜타센을 50 nm의 두께로 증착한 유기물 박막을 사용하였고 전극은 50 nm 두께의 Au 박막을 사용하였다. Au 전극과 펜타센 박막 사이에 2$\sim$8 nm 두께의 금속산화물 박막을 삽입하였으며 금속산화물의 종류와 두께에 따라 전기적 특성과 UV 광전자 분광 (ultraviolet photoelectron spectroscopy, UPS) 분석을 통해 에너지 준위의 변화를 관찰하였다. 실험 결과, 전극에 WO$_3$를 삽입한 OTFT는 전하이동도가 8.80 $\times$ 10$^{-3}$ cm$^2$/V$\cdot$s에서 최대 2.48 $\times$ 10$^{-2}$ cm$^2$/V$\cdot$s까지 증가하였고 문턱전압도 -12.3 V에서 최대 -4.09 V까지 감소하였다. TiO$_2$를 삽입한 OTFT는 전하이동도가 7.04 $\times$ 10$^{-3}$ cm$^2$/V$\cdot$s 로 감소하였으며 문턱전압은 -3.38 V 까지 감소하였다. UPS 분석 결과 WO$_3$ 박막을 삽입하면 OTFT의 에너지 장벽이 낮아지고 TiO$_2$ 박막을 삽입하면 OTFT의 에너지 장벽이 높아지는 것을 확인할 수 있었다.