http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Optical parameters of boron-doped ZnO nanorods grown by low-temperature hydrothermal reaction.
Kim, Soaram,Park, Hyunggil,Nam, Giwoong,Yoon, Hyunsik,Kim, Younggyu,Kim, Byunggu,Ji, Iksoo,Kim, Jong Su,Kim, Jin Soo,Kim, Do Yeob,Kim, Sung-O,Leem, Jae-Young American Scientific Publishers 2014 Journal of Nanoscience and Nanotechnology Vol.14 No.11
<P>Sol-gel spin-coating was used to deposit ZnO seed layers onto quartz substrates, and ZnO nanorods doped with various concentrations of B (i.e., BZO nanorods) ranging from 0 to 2.0 at% were hydrothermally grown on the ZnO seed layers. The effects of B doping on the absorption coefficient, optical band gap, Urbach energy, refractive index, extinction coefficient, single-oscillator energy, dispersion energy, average oscillator strength, average oscillator wavelength, dielectric constant, and optical conductivity of the hydrothermally grown BZO nanorods were investigated. The optical band gaps were 3.255, 3.243, 3.254, 3.258, and 3.228 eV for the nanorods grwon at 0, 0.5, 1.0, 1.5 and 2.0 at% B, respectively. B doping increased the Urbach energy from 40.7 to 65.1 meV for the nanorods grown at 0 and 2.0 at% B, respectively, and significantly affected the dispersion energy, the single-oscillator energy, the average oscillator wavelength, the average oscillator strength, the refractive index, and the optical conductivity of the hydrothermally grown BZO nanorods.</P>
Yoon, Hyunsik,Kim, Soaram,Park, Hyunggil,Nam, Giwoong,Kim, Yangsoo,Leem, Jae-Young,Kim, Min Su,Kim, Byunggu,Kim, Younggyu,Ji, Iksoo,Park, Youngbin,Kim, Ikhyun,Lee, Sang-heon,Jung, Jae Hak,Kim, Jin Soo Korean Physical Society 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.1
Undoped ZnO and Ga-doped ZnO (GZO) thin films with different Ga concentrations were prepared by using the sol-gel spin-coating method. The surface morphologies and the growth orientations of the films were measured by using scanning electron microscopy and X-ray diffraction, respectively. The electrical properties were measured by using the Hall effect. The optical transmittances and reflectances of the films were measured as functions of the wavelength by UV-vis spectroscopy. The undoped ZnO thin films exhibited rough surfaces with particle-like structures. When Ga was incorporated, the particle sizes dramatically decreased without changes in the surface morphologies, and the c-axis growth orientations of the GZO thin films were significantly decreased. The optical transmittances clearly exhibited shifts in the band edge, and those in the visible range gradually increased with increasing Ga concentration. The absorption coefficients, refractive indices, extinction constants, dielectric constants, and optical conductivities of the films gradually decreased with increasing Ga concentration.
Photoluminescence properties of defect emissions in Al-doped ZnO nanorod array thin films.
Kim, Soaram,Nam, Giwoong,Park, Hyunggil,Yoon, Hyunsik,Kim, Min Su,Kim, Do Yeob,Kim, Sung-O,Leem, Jae-Young American Scientific Publishers 2013 Journal of Nanoscience and Nanotechnology Vol.13 No.9
<P>The power- and temperature-dependent photoluminescence properties of Al-doped ZnO nanorod array thin films grown by the hydrothermal method were investigated. The intensities of both the near-band-edge emission (NBE) and deep-level emission (DLE) as well as the overall spectral line shape were strongly affected by the excitation power. At low excitation power, the blue emission was found to show the highest intensity among the different emission lights. A low-temperature photoluminescence analysis revealed the bound-exciton-related luminescence peak at 3.362 eV. The dependence of peak energy with the excitation power indicates that these DLE processes are generated by DAP transitions. The overall intensity of DLE was found to decrease as the temperature increases. With regard to the blue emission (around 2.52 eV), it showed a well-pronounced shoulder at 200 K. The activation energy for this blue emission was 51.93 meV, which corresponds to the thermal dissociation energy required for the donor-acceptor pair transitions.</P>
Kim, Hyunmi,Lee, Kyeyoon,Hwang, Hyunsik,Bhatnagar, Nikita,Kim, Dool-Yi,Yoon, In Sun,Byun, Myung-Ok,Kim, Sun Tae,Jung, Ki-Hong,Kim, Beom-Gi Oxford University Press 2014 Journal of experimental botany Vol.65 No.2
<P>Abscisic acid (ABA) is a phytohormone that plays important roles in the regulation of seed dormancy and adaptation to abiotic stresses. Previous work identified OsPYL/RCARs as functional ABA receptors regulating ABA-dependent gene expression in <I>Oryza sativa</I>. <I>OsPYL</I>/<I>RCAR</I>s thus are considered to be good candidate genes for improvement of abiotic stress tolerance in crops. This work demonstrates that the cytosolic ABA receptor OsPYL/RCAR5 in <I>O. sativa</I> functions as a positive regulator of abiotic stress-responsive gene expression. The constitutive expression of <I>OsPYL/RCAR5</I> in rice driven by the <I>Zea mays ubiquitin</I> promoter induced the expression of many stress-responsive genes even under normal growth conditions and resulted in improved drought and salt stress tolerance in rice. However, it slightly reduced plant height under paddy field conditions and severely reduced total seed yield. This suggests that, although exogenous expression of OsPYL/RCAR5 is able to improve abiotic stress tolerance in rice, fine regulation of its expression will be required to avoid deleterious effects on agricultural traits.</P>
김정아,정현식,김원석,윤성수,이홍기,박찬형,박성규,김동욱,이종욱,한치화,민우성,김춘추,김동집 대한조혈모세포이식학회 1996 대한조혈모세포이식학회지 Vol.1 No.1
Background: In most solid tumors, the CD34 antigen has not been detected, so positive selection of CD34+ cells may reduce tumor cell contamination and the CD34+ cells are capable of reconstituting hematopoiesis. We tried CD34+ cell transplantation in two patients. Method: CD34+ cells from chemotherapy + G-CSF mobilized PBPCs or bone marrow were positively selected with an avidin-biotin immunoadsorption column (CEPRATE SC system). Case 1. One course of chemotherapy using cyclophosphamide(200㎎/㎡) and etoposide (4.2g/㎡), combined with G-CSF(5㎍/㎏) S.C. was used in a relapsed lymphoma patient. This patient responded to the induction chemotherapy. CD34+ cells from harvested bone marrow were selected by the CellPro immunoadsorption column. The total number of mononuclear cells loaded onto the CellPro was 2.4×10^(8)/㎏, with 1.1% CD34+ cells. After column separation, the total number of positively selected cells was 5.16×10^(6)/㎏. The number of CFU-GM was 76.8×10⁴/㎏. This patient was treated with melphalan (140㎎/㎡) and TBI (1200cGy) and the positively selected CD34+ cells were infused. The time to neutrophil recovery greater than 0.5×10^(9)/L was 19 days and the time to platelet recovery greater than 50×10^(9)/L was 21 days. Case 2. Two courses of mobilizing chemotherapy were given 4 weeks apart using taxol(210㎎/m2) and adriamycin(60㎎/m2), combined with G-CSF(5㎍/㎏) S.C. in a breast cancer patients with 7 axillary node metastasis. CD34+ cells from each single leukapheresis product were selected by the CellPro immunoadsorption column. In the first collection, the total number of nucleated cells was 4.4×10^(8)/kg, with 0.42% CD34+ cells. In the second collection, the total number of nucleated cell was 2.8× 10^(8)/㎏ with 0.43% CD34+ cells. After colum separation, the total numbers of collected cells were 4.0×106/kg and 4.8×10^(6)/kg, the total number of CD34+ cells were 1.2×10^(6)/㎏ and 0.82×10^(6)/㎏. Colonogenic assays of positively selected CD34+ cells gave rise to myeloid erythroid, and multilineage colonies, with a median of 190 CFU-GM, 190 BFU-E, and 164 CFU-GEMM per 1×10³ adsorbed cells, respectively. High-dose chemotherapy with cumulative doses of 40mg/㎡ mitoxantrone, 750mg/㎡ thioptepa, and 1000mg/㎡ carboplatin was administered. Positively selected CD34+ cells were rapidly infused 24 hours after the end of high-dose chemotherapy. The time to neutrophil recovery greater than 0.5×10^(9)/L was 16 days and the time to platelet recovery greater than 50×10^(9)/L was 20 days.
Kim, Soaram,Nam, Giwoong,Park, Hyunggil,Yoon, Hyunsik,Lee, Sang-Heon,Kim, Jong Su,Kim, Jin Soo,Kim, Do Yeob,Kim, Sung-O,Leem, Jae-Young Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.4
The structural and optical properties of the ZnO, Al-doped ZnO, Ga-doped ZnO, and In-doped ZnO nanorods were investigated using field-emission scanning electron microscopy, X-ray diffraction, photoluminescence (PL) and ultraviolet-visible spectroscopy. All the nanorods grew with good alignment on the ZnO seed layers and the ZnO nanorod dimensions could be controlled by the addition of the various dopants. For instance, the diameter of the nanorods decreased with increasing atomic number of the dopants. The ratio between the near-band-edge emission (NBE) and the deep-level emission (DLE) intensities ($I_{NBE}/I_{DLE}$) obtained by PL gradually decreased because the DLE intensity from the nanorods gradually increased with increase in the atomic number of the dopants. We found that the dopants affected the structural and optical properties of the ZnO nanorods including their dimensions, lattice constants, residual stresses, bond lengths, PL properties, transmittance values, optical band gaps, and Urbach energies.
Nambin Kim,Woong Jung,Donghoon Shin,Hongwoo Seo,Hyungsang Kim,Hyunsik Im,Kyooho Jung,Soonkoo Kim,Sungchan Kim,Yongmin Kim 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.3
We investigated the (ballistic) current-voltage (I-V ) characteristics in a 100-nm ..-gate AlGaAs/InGaAs Pseudomorphic high-electron-mobility transistor (pHEMT) as a function of temperature for temperatures ranging from 300 K to 10 K and analyzed the transport in terms of carrier backscattering. We observed that the drain current in the linear region dramatically increased below 60 K due to reduced phonon scattering. The critical temperature where the drain current started to rapidly increase shifted to a higher value as the drain voltage was increased. These results are in good agreement with the ballistic transport theory in which low temperatures and high electric fields along the channel lead to enhanced ballistic transport due to a reduction in the backscattering probability. We also carried out self-consistent Schrodinger-Poisson band profile calculations to understand the experimental data.
100% ASK 수신기를 위한 13.56㎒ RFID Tag용 클럭 복원회로 설계
김지곤(Jigon Kim),이경일(Kyeong-il Yi),김현식(Hyunsik Kim),김재환(J. H. Kim),김효종(Hyojong Kim),김시호(Shiho Kim) 대한전자공학회 2008 電子工學會論文誌-SD (Semiconductor and devices) Vol.45 No.11
ASK 100% RF 입력신호를 이용하는 13.56㎒ RFID 태그를 위한 클럭 복원회로를 제안하였다. 제안한 클럭 복원회로는, 레지스터로 조절되는 DLL을 이용하여 입력 RF 신호의 크기가 0인 구간에서도 기준 클럭 신호를 사용하지 클럭을 생성하도록 설계되었다. 제안한 회로는 TSMC 0.18㎛ 1P6M 공정을 사용하여 설계하였으며, 제안된 회로는 DLL의 위상 잠김 시간이 6.4usec 이하이며 공급전압이 3.3V에서 43uW를 소모한다. We have proposed a clock recovery circuit for 13.56㎒ RFID Tags using 100%, ASK RF input signal. The proposed clock recovery circuit generates clock pulses without reference clock by adapting register controlled DLL. The proposed circuit have designed by using a TSMC 0.18㎛ 1P6M CMOS technology. The simulated results show that the phase locking time of the proposed circuit is about 6.4 usec and power consumption is about 43㎼ at supply voltage of 3.3V.
해시태그를 통한 감정 공유가 지각된 관심 끌기와 사회적 상호작용성에 미치는 영향
김민지(Minji Kim),김보명(Bomyung Kim),김현영(Hyunyoung Kim),백서연(Seoyeon Baek),신현식(Hyunsik Shin),이인성(Inseong Lee),김진우(Jinwoo Kim) 한국HCI학회 2016 한국HCI학회 학술대회 Vol.2016 No.1
소셜 미디어를 통한 감정 공유가 증가하고 있다. 감정공유는 타인의 공감을 얻고 ‘좋아요’나 댓글과 같은 사회적 상호작용을 증가시키기 위해 이루어진다. 그러나 지나친 감정 공유로 인해 오히려 타인의 공감을 얻지 못하고 관심 끌기라고 판단되는 경우가 나타나고 있다. 관심 끌기를 목적으로 한다고 판단되는 게시물에 대해 사용자들은 공감하지 못하고 사회적 상호작용을 줄이게 된다. 관심 끌기라고 판단하게 되는 원인 중 하나로 해시태그(#)를 통한 감정 공유가 있다. 기존의 해시태그는 게시물의 주제를 나타내는 키워드로 주로 사용되었으나 최근에는 직접적인 감정 공유의 수단으로도 사용되고 있다. 본 연구에서는 해시태그가 강조성과 보편성이라는 수사적 기능을 수행하며 이러한 기능이 감정 공유에 있어 관심 끌기라고 판단하게 되는데 영향을 줄 것이라고 생각하였다. 이러한 관계를 알아보기 위해 본 연구에서는 해시태그를 통해 감정을 공유하는 가상의 게시물을 제작하여 설문 조사를 실시하였다. 연구 결과 관심 끌기를 목적으로 하고 있다고 생각될수록 게시물에 대한 ‘좋아요’ 수가 감소함을 확인하였다. 또한 공유된 감정이 강조되었고 보편적이지 않다고 생각될수록 관심 끌기라고 판단하는 것으로 나타났다. Emotion sharing on social media is flourishing. People share their feelings to increase social interactions such as ‘like’ and comment. Due to the excessive sharing, however, some people have failed appealing and perceived as attention seekers. People do not empathize with an attention seeking post and decrease the number of social interaction. Emotion shared with hashtag(#) is a classic example which is perceived as an attention seeking. Although hashtag has usually represented a keyword of a post, recently it becomes an emotion delivering method. In this study, we hypothesized that the rhetorical function of hashtag affects the judgment of attention seeking. To verify the hypotheses, we conducted a survey with prototype system. The result indicated that as people perceived the post as attention seeking, the number of ‘like’ decreased. In addition, people tend to judge the post as attention seeking, when they think shared emotion is emphasized and unique.