Browsing by Issue Date, starting with "2004-05-24"

Now showing 1 - 20 of 70140

Competition between the charge ordered and ferromagnetic states in (La,Nd)(0.75)Na0.25MnO3 manganites
(2004-05-24)
Li, ZQ
;
Zhang, XH
;
Yu, JS
;
Liu, XJ
;
Liu, XD
Structural, magnetic, and transport properties of (La1-xNdx)(0.75)Na0.25MnO3 (0 less than or equal to x less than or equal to 1) are studied. The system exhibits a rhombohedrally distorted perovskite structure for x less than or equal to 0.2 and it convert to an orthorhombic structure for x greater than or equal to 0.4. Re-entrant ferromagnetic type charge ordering transitions are observed in the narrow bandwidth samples (x greater than or equal to 0.6), while charge ordering transition is not observed for these samples with rhombohedral structure. Combining with the published results related to the charge ordering transition, we argue that the rhombohedral structure likely favor double exchange interaction and suppress charge ordering interaction. The compounds show metal to insulator transitions except Nd0.75Na0.25MnO3. The resistivity data above the metal to insulator transition temperature for the charge ordered sample are discussed in the frame work of variable-range hopping model. (C) 2004 Elsevier B.V. All rights reserved.
EFBLA: a two-phase matching algorithm for fast motion estimation
(2004-05-27)
Cheng, HW
;
Dung, LR
;
電控工程研究所
;
Institute of Electrical and Control Engineering
A novel motion estimation algorithm that contains edge matching and block matching is presented. The edge matching reduces candidates for the block matching that performs accurate searching. Thus, the two-phase procedure speeds up motion estimation. As a result, edge-matching first block-matching last algorithm (EFBLA) may significantly save the computation load by 93.9%.
Resonator-based multi-stage Sigma Delta modulator for wideband applications with improved dynamic range
(2004-05-27)
Chang, TH
;
Dung, LR
;
電控工程研究所
;
Institute of Electrical and Control Engineering
A new design methodology for wideband, multi-stage, multi-bit YEA modulators (SigmaDeltaMs) with improved dynamic range, is presented. The key to improving dynamic range is to have the first stage oscillated, then the coarse quantisation noise vanishes and hence circuit nonlinearities do not cause a leakage quantisation noise problem. Based on the proposed methodology, a fourth-order four-bit SigmaDeltaM can achieve the dynamic range of 80 dB at the OSR of 8 without using additional calibration techniques.
Pev cosmic neutrinos from the mountains
(2004-05-30)
Yeh, P
;
Athar, H
;
La Barbera, N
;
Bouaissi, S
;
Catalano, O
The NuTel collaboration is building a wide field-of-view Cerenkov telescope to be installed on a mountain site for observing near horizontal air showers emerging from another mountain. Cosmic tau neutrinos is the primary source of such showers. This technique will be realized for the first time in the v, energy range of 2 PeV to 1000 PeV. The telescope has enough sensitivity to observe cosmic neutrinos from sources like Active Galactic Nuclei and Galactic Center assuming fluxes from current theoretical models.
Affleck-dine baryogenesis in a string model
(2004-05-30)
Dolgov, AD
;
Kohri, K
;
Seto, O
;
Yokoyama, J
;
物理研究所
Entropy production by a dilaton decay is studied in the model where the dilaton acquires potential via gaugino condensation in the hidden gauge group. Its effect on the Affleck-Dine baryogenesis is investigated. It is shown that the baryon asymmetry produced by this mechanism with the higher-dimensional terms is diluted by the dilaton decay and can be regulated to the observed value.
What do we mean by detecting earth-skimming of neutrinos?
(2004-05-30)
Lin, GL
;
物理研究所
;
Institute of Physics
In this talk, we elaborate the strategy for detecting the Earth-skimming tau neutrinos. We first show that there are non-negligible astrophysical tau neutrino fluxes due to neutrino flavor oscillations. We then illustrate the idea of detecting Earth-skimming tau neutrinos. In particular, we point out that the tau-lepton flux resulting from neutrino-nucleon scatterings inside the earth is controlled by the tau-lepton range. We demonstrate this observation by showing the tau-lepton flux induced by the GZK tau-neutrino flux. The question on the energy resolutions of tau neutrinos in this detection strategy is briefly discussed.
Prediction of the bonding states of cysteines using the support vector machines based on multiple feature vectors and cysteine state sequences
(2004-06-01)
Chen, YC
;
Lin, SC
;
Lin, CJ
;
Hwang, JK
;
生物科技學系
The support vector machine (SVM) method is used to predict the bonding states of cysteines. Besides using local descriptors such as the local sequences, we include global information, such as amino acid compositions and the patterns of the states of cysteines (bonded or nonbonded), or cysteine state sequences, of the proteins. We found that SVM based on local sequences or global amino acid compositions yielded similar prediction accuracies for the data set comprising 4136 cysteine-containing segments extracted from 969 nonhomologous proteins. However, the SVM method based on multiple feature vectors (combining local sequences and global amino acid compositions) significantly improves the prediction accuracy, from 80% to 86%. If coupled with cysteine state sequences, SVM based on multiple feature vectors yields 90% in overall prediction accuracy and a 0.77 Matthews correlation coefficient, around 10% and 22% higher than the corresponding values obtained by SVM based on local sequence information. (C) 2004Wiley-Liss, Inc.
石牌醫訊第３４１期
(國立陽明大學, 2004-06-01)
陽明電子報編輯小組
日　期：2004年5月30日-2004年6月5日時間：93年5月30日（星期日），9:00-4:00 地點：活動中心六樓‧山腰上的家講者：王理書　教育科技與諮商雙碩士（美國堪薩斯州立大學）講題：關係裡的自我映照─深層自我的隱喻、關係與自我的整合 ─神奇隱喻的產生與述說‧整合與治療時間：93年5月31日（星期一）12:00-13:10 地點：實驗大樓3F A101 講者：陳家俊教授（師大化學系）講題：奈米材料之生醫應用時間：93年 5月31日（星期一）12:20-13:20 地點：生化所501教室講者：Professor Brenda Kahan （Department of Biomolecular Chemistry, University of Wisconsin）講題：Derivation of Pancreatic Islet Cells from Embryonic Stem Cells 時間：93年5月31日（星期一）下午3:00 地點：微免所 401室講者：許輝吉　教授 (台大病理所) 講題：Hepatocellular carcinoma: Pathology, molecular pathology, and beyond 時間：93年5月31日（星期一）18:30~21:30 地點：山腰大廳講者：李俊宏　醫師（台北市立療養院）講題：電影院及討論會（?美麗境界?老大靠邊閃?火柴人）時間：93年5月31日~ 6月7日(weekday)；每日第七、八堂地點：傳醫大樓乙棟 401 室講者：Professor Lawrence Kahan（ University of Wisconsin ）講題：Structure/function relationships in blood proteins 時間：93年6月1日（星期二）8:10-4:00 地點：活動中心第一會議室講題：陽明醫學教育基金會紀念尹珣若先生碩士班論文比賽時間：93年6月1日（星期二）中午12:00 地點：陽明大學護理館三樓301會議室講者：林姝君　副教授 (口腔生物研究所) 講題：Molecular alterations in areca-associated oral cancer 檳榔口腔癌之分子變異時間：93年6月2日（星期三）10:10-12:00 地點：活動中心第三會議室講者：花亦芬　助理教授講題：期末討論時間：93年6月2日（星期三）晚上7:00-9:00 地點：公務人力發展中心（台北市新生南路三段３０號）講者：公務人力發展中心講員講題：人生哲學時間：93年6月3~4日（星期四~五），8:10-5:30 地點：實驗大樓B1區會議室(原育成中心) 講者：Prof. Hiroshi Masuhara （Head of the Department of Applied Physics,Osaka University, Japan）講題：spectroscopy and nano imaging (I)、spectroscopy and nano imaging (Il) 時間：93年6月4日（五）上午10:10- 2:00 地點：研究大樓 103 室講者：呂育道　教授（ PH.D. in Compuiter Science, Harvard University, 台灣大學, 資訊工程學系及財務金融學系）講題：From Financial Derivatives (衍生性金融商品) to Diffusion Equation 時間：93年6月4日 (星期五) 下午 13:30-14:30 地點：研究大樓 202 室講者：呂　仁博士講題：1. Molecular mechanism of Epstein-Barr virus-enhanced cell migration andproliferation EB病毒增進細胞轉移及增生之分子機制 2. Systematic analysis the biological functions of secreted and transmembrane proteins in stem cells 系統性研究胞外蛋白及膜蛋白在幹細胞中的作用時間：93 年 6月4日（星期五）下午13:30-15:20 地點：傳醫大樓乙棟四樓微免所 401 教室講者：Dr. Hsin-Ling Hsu (徐欣伶)（ Research Assistant Professor Northwestern University Medical School , Chicago, IL）講題：1. Ku acts in a unique way at the mammalian telomere to prevent end joining 2. The MCT-1 oncogene transforms human mammary epithelial cells and deregulates DNA damage response ３４２期截稿日期：93年6月10日（星期四）上午十二時正，敬請踴躍提供訊息。
夏日炎炎．力爭上游 ─ 水上運動大會現場實況轉播
(國立陽明大學, 2004-06-01)
陽明電子報編輯小組
5/25早上，游泳池畔陣陣的喧鬧聲，震天價響。一年一度的水上運動大會歡樂登場，請看我們的現場實況轉播
搶救生命，你準備好了嗎？
(國立陽明大學, 2004-06-01)
陽明電子報編輯小組
5/28（五）上午十時，前環保署署長，現任紅十字會秘書長的郝龍斌先生，在他夫人高閬仙老師的陪伴下，輕鬆地步入本校活動中心第一會議室。郝秘書長這天是應通識中心邀請，為全校師生演講＜搶救生命，你準備好了嗎？＞一小時的演講過程中.
A novel washout filter design for a six degree-of-freedom motion simulator
(2004-06-01)
Liao, CS
;
Huang, CF
;
Chieng, WH
;
機械工程學系
;
Department of Mechanical Engineering
The motion cue performed by a motion simulator is restrained by the workspace of the simulator structure. A typical reasoning is then to build a large motion simulator. unless it is for entertainment, which involves in small simulators. This study proposes a novel approach to designing the washout filter of the motion control of a six degree-of-freedom motion simulator for entertainment purposes. Using information obtained from the inverse kinematics of the simulator, the workspace boundary, detected in real-time, is fed into the washout filter as a reference for the motion planning. The main focus of this approach is to make the motion cue feasible for use in a simulator with a restricted workspace, while ensuring the robustness of the driving system. In this paper, different indices are established to specify the performance of the motion cue. A classical linear washout filter was implemented and compared with the proposed washout filter using the performance indices to demonstrate the benefits of the latter.
選擇性沉積碳奈米結構於矽晶基材之方法
(2004-06-01)
郭正次
;
張惠林
;
林兆焄
;
許智明
本發明選擇性沉積碳奈米結構於矽晶基材之方法，依序包含下列步驟：於矽晶基材上決定欲成長碳奈米結構的區域；於欲成長碳奈米結構的區域生長金屬矽化物；於金屬矽化物表面利用化學氣相沉積法成長碳奈米結構。由於在矽晶基材上之金屬矽化物區域即為碳奈米結構成長區域，因而達到選擇性沉積碳奈米結構之目的，另且，該金屬矽化物區域係由半導體製程方法製造，所以本發明的製程方法與現有半導體設備相容性高。
Shot-noise spectrum of superradiant entangled excitons
(2004-06-01)
Chen, YN
;
Brandes, T
;
Li, CM
;
Chuu, DS
;
電子物理學系
The shot noise produced by tunneling of electrons and holes into a double dot system incorporated inside a p-i-n junction is investigated theoretically. The enhancement of the shot noise is shown to originate from the entangled electron-hole pair created by superradiance. The analogy to the superconducting Cooper pair box is pointed out. A series of Zeno-like measurements is shown to destroy the entanglement, except for the case of maximum entanglement.
Phenomenology of a TeV right-handed neutrino and the dark matter model
(2004-06-01)
Cheung, KM
;
Seto, O
;
物理研究所
;
Institute of Physics
In a model of a TeV right-handed (RH) neutrino by Krauss, Nasri, and Trodden, the sub-eV scale neutrino masses are generated via a three-loop diagram with the vanishing seesaw mass forbidden by a discrete symmetry, and the TeV mass RH neutrino is simultaneously a novel candidate for cold dark matter. However, we show that with a single RH neutrino it is not possible to generate two mass-square differences as required by the oscillation data. We extend the model by introducing one more TeV RH neutrino and show that it is possible to satisfy the oscillation pattern within the modified model. After studying in detail the constraints coming from the dark matter, lepton flavor violation, the muon anomalous magnetic moment, and the neutrinoless double beta decay, we explore the parameter space and derive predictions of the model. Finally, we study the production and decay signatures of the TeV RH neutrinos at TeV e(+)e(-)/mu(+)mu(-) colliders.
Robot motion classification from the standpoint of learning control
(2004-06-01)
Shiah, SJ
;
Young, KY
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In robot learning control, the learning space for executing the general motions of multi-joint robot manipulators is very complicated. Thus, when the learning controllers are employed as major roles in motion governing, the motion variety requires them to consume excessive amount of memory. Therefore, in spite of their ability to generalize, the learning controllers are usually used as subordinates to conventional controllers or the learning process needs to be repeated each time a new trajectory is encountered. To simplify learning space complexity, we propose, from the standpoint of learning control, that robot motions be classified according to their similarities. The learning controller can then be designed to govern groups of robot motions with high degrees of similarity without consuming excessive memory resources. Motion classification based on using the PUMA 560 robot manipulator demonstrates the effectiveness of the proposed scheme. (C) 2003 Elsevier B.V. All rights reserved.
Synthetic quasi-TEM meandered transmission lines for compacted microwave integrated circuits
(2004-06-01)
Chen, CC
;
Tzuang, CKC
;
傳播研究所
;
Institute of Communication Studies
This paper presents a two-dimensional transmission line (2-D TL) that supports quasi-TEM propagation mode and reduces problems associated with compacted meandering of microstrip (MS) on propagation constants and the characteristic impedances commonly observed in conventional one-dimensional MSs. The proposed 2-D TL comprises two layers of metallic surfaces on either side of a dielectric substrate. The top metal surface is a meandered connection of a unit cell with a central patch and connecting arms. The bottom surface is a meshed 2-D periodical ground plane, whose etched portion complements the patch portion of the too surface, forming a complementary-conducting-strip (CCS) TL, enabling a combination of an MS and MS with the tuning septa in a unit cell. Both theoretical and experimental investigations of the CCS TL agree well and demonstrate that it is much less susceptible to the effects of meanderings on the propagation constant and characteristic impedance than an MS for the same meandered pattern. Two design examples are presented to demonstrate the potential for a CCS TL for miniaturizing microwave passive circuits with minimal losses. The first example involves a 5.4-GHz CCS four-port rat-race hybrid, realized in RO4003 and reduces the area of original MS design by 87%. The second example illustrates the applicability of a CCS TL to a monolithic RF integrated circuit using a first-pass design of a 5.2-GHz CMOS oscillator incorporating a CCS TL as a resonator with an area totaling 500 x 600 mum(2) including pads base on Taiwan Semiconductor Manufacturing Company's 0.25-mum 1P5M CMOS process techniques.
Anisotropic pinning effect on a Nb thin film with triangular arrays of pinning sites
(2004-06-01)
Wu, TC
;
Kang, PC
;
Horng, L
;
Wu, JC
;
Yang, TJ
A superconducting Nb thin film with triangular arrays of pinning sites has been fabricated to investigate the commensurate vortex lattices. Vortex-vortex interactions in this pattern film make the observed anisotropy in the pinning properties. Periodic minima appear in the magnetoresistance curves at equal field intervals that can be associated with matching effect. The transport properties at near critical temperatures show anisotropic pinning properties related to the configuration of pinning centers. The critical current is depressed when the driving force is applied along the short diagonal in the rhombic unit cell of pinning array. It implies that the pinning potential along the short diagonal creates a moving channel of vortices in triangular arrays of defects. The pinned and interstitial vortices can be movable in an incommensurate vortex row and a straight unhindered one-dimensional path. (C) 2004 American Institute of Physics.
我愛夏天 ─ 擁抱四校沙攤派對
(國立陽明大學, 2004-06-01)
生命科學系系學會編輯部
;
陽明電子報編輯小組
在艷陽的祝福之下，由陽明大學生命科學系系學會舉辦的「我愛夏天─擁抱四校沙攤派對」5/29在通宵西濱海洋教育園區登場，為了要讓陽明生科系的學生可以跟其他學校生科系有更進一步的交流，陽明生科系學會花上一個學期的時間籌備這場沙灘派對，花上許多巧思、創新，努力聯絡中央大學、清華大學、交通大學的生命科學系，期待他們能夠加入這場夏日盛宴。
Effect of polar substituents on the properties of 1,3,4-oxadiazole-based liquid crystalline materials containing asymmetric cores
(2004-06-01)
Sung, HH
;
Lin, HC
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A series of 1,3,4-oxadiazole-based liquid crystals bearing different polar substituents (n-NPO-X, where X = Me, OMe, Cl, F, CN, and NO2) at the phenyl 4-position have been synthesized and characterized. These angular oxadiazole-based liquid crystals, which are composed of asymmetric cores containing naphthalene units, exhibit stable mesogenic properties including the nematic and smectic A phases. With analogous structural design, the transition temperatures, mesomorphic phases, optical properties, and internal quantum efficiencies show strong dependence on the terminal substitution. In general, by increasing the terminal dipoles, the temperature ranges of the mesophases are enhanced, and both the absorption and photoluminescence spectra are shifted to longer wavelengths.
Synthesis and second-order nonlinearities of chiral prolinol-substituted chromophores
(2004-06-01)
Chou, SSP
;
Yu, CY
;
Lin, HC
;
Yang, PK
;
光電工程學系
A new series of thiophene- and furan-containing chromophores with a chiral prolinol donor and a sulfone acceptor has been synthesized. The UV-vis absorptions, second-order nonlinear optical properties, and X-ray crystal structures are described.