Browsing by Issue Date, starting with "2010-02-23"

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Pyrazole compound BPR1P0034 with potent and selective anti-influenza virus activity
(2010-02-23)
Shih, Shin-Ru
;
Chu, Tzu-Yun
;
Reddy, Gadarla Randheer
;
Tseng, Sung-Nain
;
Chen, Hsiun-Ling
Background: Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals. Methods: We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle. Results: The 50% effective inhibitory concentration (IC(50)) of BPR1P0034 was 0.42 +/- 0.11 mu M, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus. Conclusions: To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-mu M) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent.
Reconstructing genome trees of prokaryotes using overlapping genes
(2010-02-24)
Cheng, Chih-Hsien
;
Yang, Chung-Han
;
Chiu, Hsien-Tai
;
Lu, Chin Lung
;
生物科技學系
Background: Overlapping genes (OGs) are defined as adjacent genes whose coding sequences overlap partially or entirely. In fact, they are ubiquitous in microbial genomes and more conserved between species than nonoverlapping genes. Based on this property, we have previously implemented a web server, named OGtree, that allows the user to reconstruct genome trees of some prokaryotes according to their pairwise OG distances. By analogy to the analyses of gene content and gene order, the OG distance between two genomes we defined was based on a measure of combining OG content (i.e., the normalized number of shared orthologous OG pairs) and OG order (i.e., the normalized OG breakpoint distance) in their whole genomes. A shortcoming of using the concept of breakpoints to define the OG distance is its inability to analyze the OG distance of multi-chromosomal genomes. In addition, the amount of overlapping coding sequences between some distantly related prokaryotic genomes may be limited so that it is hard to find enough OGs to properly evaluate their pairwise OG distances. Results: In this study, we therefore define a new OG order distance that is based on more biologically accurate rearrangements (e. g., reversals, transpositions and translocations) rather than breakpoints and that is applicable to both uni-chromosomal and multi-chromosomal genomes. In addition, we expand the term "gene" to include both its coding sequence and regulatory regions so that two adjacent genes whose coding sequences or regulatory regions overlap with each other are considered as a pair of overlapping genes. This is because overlapping of regulatory regions of distinct genes suggests that the regulation of expression for these genes should be more or less interrelated. Based on these modifications, we have reimplemented our OGtree as a new web server, named OGtree2, and have also evaluated its accuracy of genome tree reconstruction on a testing dataset consisting of 21 Proteobacteria genomes. Our experimental results have finally shown that our current OGtree2 indeed outperforms its previous version OGtree, as well as another similar server, called BPhyOG, significantly in the quality of genome tree reconstruction, because the phylogenetic tree obtained by OGtree2 is greatly congruent with the reference tree that coincides with the taxonomy accepted by biologists for these Proteobacteria. Conclusions: In this study, we have introduced a new web server OGtree2 at http://bioalgorithm.life.nctu.edu.tw/ OGtree2.0/ that can serve as a useful tool for reconstructing more precise and robust genome trees of prokaryotes according to their overlapping genes.
Charge storage characteristics of high density Mo nanocrystal embedded in silicon oxide and silicon nitride
(2010-02-24)
Lin, Chao-Cheng
;
Chang, Ting-Chang
;
Tu, Chun-Hao
;
Chen, Shih-Ching
;
Hu, Chih-Wei
We investigated the formation and charge storage characteristics of Mo nanocrystals in silicon oxide and in silicon nitride by rapid thermal annealing of oxygen- and nitrogen-incorporated Mo and Si mixed layers. A high density of Mo nanocrystal (6 x 10(12) cm(-2)) was formed in the nitrogen-incorporated layer. Electrical analyses indicated that the memory window of the Mo nanocrystal embedded in the nitride is larger than that in the oxide. A reliability test showed that the Mo nanocrystal in the nitride has better reliability than the Mo nanocrystal in the oxide, which was explained by an electrical field simulation.
Reconstructing genome trees of prokaryotes using overlapping genes
(2010-02-24)
Cheng, Chih-Hsien
;
Yang, Chung-Han
;
Chiu, Hsien-Tai
;
Lu, Chin Lung
;
生物科技學系
Background: Overlapping genes (OGs) are defined as adjacent genes whose coding sequences overlap partially or entirely. In fact, they are ubiquitous in microbial genomes and more conserved between species than nonoverlapping genes. Based on this property, we have previously implemented a web server, named OGtree, that allows the user to reconstruct genome trees of some prokaryotes according to their pairwise OG distances. By analogy to the analyses of gene content and gene order, the OG distance between two genomes we defined was based on a measure of combining OG content (i.e., the normalized number of shared orthologous OG pairs) and OG order (i.e., the normalized OG breakpoint distance) in their whole genomes. A shortcoming of using the concept of breakpoints to define the OG distance is its inability to analyze the OG distance of multi-chromosomal genomes. In addition, the amount of overlapping coding sequences between some distantly related prokaryotic genomes may be limited so that it is hard to find enough OGs to properly evaluate their pairwise OG distances. Results: In this study, we therefore define a new OG order distance that is based on more biologically accurate rearrangements (e. g., reversals, transpositions and translocations) rather than breakpoints and that is applicable to both uni-chromosomal and multi-chromosomal genomes. In addition, we expand the term "gene" to include both its coding sequence and regulatory regions so that two adjacent genes whose coding sequences or regulatory regions overlap with each other are considered as a pair of overlapping genes. This is because overlapping of regulatory regions of distinct genes suggests that the regulation of expression for these genes should be more or less interrelated. Based on these modifications, we have reimplemented our OGtree as a new web server, named OGtree2, and have also evaluated its accuracy of genome tree reconstruction on a testing dataset consisting of 21 Proteobacteria genomes. Our experimental results have finally shown that our current OGtree2 indeed outperforms its previous version OGtree, as well as another similar server, called BPhyOG, significantly in the quality of genome tree reconstruction, because the phylogenetic tree obtained by OGtree2 is greatly congruent with the reference tree that coincides with the taxonomy accepted by biologists for these Proteobacteria. Conclusions: In this study, we have introduced a new web server OGtree2 at http://bioalgorithm.life.nctu.edu.tw/ OGtree2.0/ that can serve as a useful tool for reconstructing more precise and robust genome trees of prokaryotes according to their overlapping genes.
MATRIX DISPLAY INTERFACE FOR PRESENTATION SYSTEM
(2010-02-25)
Chen, Ming Jang
A matrix display interface for a presentation system includes a plurality of data units, a main switching element, a plurality of column switching elements, a plurality of row switching element, and a plurality of grid switching elements. The data units are arranged on a display interface and are written with presentation data in advance. The presentation system is operated on a computer. A user may click the switching elements to selectively display or conceal or highlight all the data units, a whole column of data units, a whole row of data units, or a single data unit. Thereby, a speaker of a presentation may selectively present the content of the presentation to draw the attention of the listeners, so that the speaker and the listeners may have positive interactions during the presentation.
Synthesis and Preclinical Evaluations of 2-(2-Fluorophenyl)-6,7-methylenedioxyquinolin-4-one Monosodium Phosphate (CHM-1-P-Na) as a Potent Antitumor Agent
(2010-02-25)
Chou, Li-Chen
;
Chen, Chien-Ting
;
Lee, Jang-Chang
;
Way, Tzong-Der
;
Huang, Chi-Hung
CHM-1 [2-(2-fluorophenyl)-6,7-methylenedioxyquinolin-4-one] (1) has a unique antitumor mechanism of action. However, because 1 has relatively low hydrophilicity, it was evaluated only via ip administration, which is not clinically acceptable. In this study, we synthesized the monosodium phosphate salt (CHM-1-P-Na, 4) of 1 as a hydrophilic prodrug. Compound 4 was rapidly converted into 1 following iv and po administration and also possessed excellent antitumor activity in a SKOV-3 xenograft nude mice model. Compound 4 also had clear-cut pharmacological effects oil enzymes related with tumor cells. Neither 4 not 1 significantly affected normal biological function in a safety pharmacology profiling study. Compound 1 caused apoptotic effects in breast carcinoma cells via accumulation of cyclin B1, and importantly, the endogenous levels of the mitotic spindle checkpoint proteins BubR1 directly correlated with cellular response to microtubule disruption. With excellent antitumor activity profiles, 4 is highly promising for development as all anticancer clinical trials candidate.
斜め堆積を用いて生成されたナノ構造薄膜およびその方法
(2010-02-25)
チア－フアチャン
;
チン－シェンヤン
;
チン－フア，チュ
;
ペイ－チェンユー
;
ハオ－チュンクオ
【課題】勾配型屈折率を備えた多孔質を含む単層構造をした透明導電性のナノ構造薄膜とその製造方法を提供する。【解決手段】電子ビームシステム１００を用いて、ターゲットソースが斜め堆積法により蒸着される。複数の調整可能な試料ステージ１０４上に蒸着基板１１４が配置される。プロセスチャンバー１０１内でガスの流量および温度を制御するため、熱源と複数のガス制御弁１０７および１０８が備えられる。蒸着後、薄膜構造と光電子特性を向上させるため、アニール工程が行われる。【選択図】図１ａ
MULTITASKING PROCESSOR AND TASK SWITCHING METHOD THEREOF
(2010-02-25)
Lin, Tay-Jyi
;
Huang, Pao-Jui
;
Liu, Chih-Wei
;
Chen, Shin-Kai
;
Wang, Bing-Shiun
A multitasking processor and a task switching method thereof are provided. The task switching method includes following steps. A first task is executed by the multitasking processor, wherein the first task contains a plurality of switching-point instructions. An interrupt event occurs. Accordingly, the multitasking processor temporarily stops executing the first task and starts to execute a second task. The multitasking processor executes a handling process of the interrupt event and sets a switching flag. After finishing the handling process of the interrupt event, the multitasking processor does not perform task switching but continues to execute the first task, and the multitasking processor only performs task switching to execute the second task when it reaches a switching-point instruction in the first task.
Anti-Influenza Drug Discovery: Structure-Activity Relationship and Mechanistic Insight into Novel Angelicin Derivatives
(2010-02-25)
Yeh, Jiann-Yih
;
Coumar, Mohane Selvaraj
;
Horng, Jim-Tong
;
Shiao, Hui-Yi
;
Kuo, Fu-Ming
By using a cell-based high throughput screening campaign,a novel angelicin derivative 6a was identified to inhibit influenza A (H1N1) virus induced Cytopathic effect in Madin-Darby canine kidney cell culture in low micromolar range. Detailed structure-activity relationship studies of 6a revealed that the angelicin scaffold is essential for activity in pharmacophore B, while meta-substituted phenyl/2-thiophene rings are optimal ill pharmacophore A and C. The optimized lead 4-methyl-9-phenyl-8-(thiophene-2-carbonyl)-furo[2,3-h]chromen-2-one (8g, IC(50) = 70 nM) showed 64-fold enhanced activity compared to the high throughput screening (HTS) hit 6a. Also, 8g was found effective in case of influenza A (H3N2) and influenza B virus strains similar to approved anti-influenza drug zanamivir (4). Preliminary mechanistic studies suggest that these compounds act as anti-influenza agents by inhibiting ribonucleoprotein (RNP) complex associated activity and have the potential to be developed further, Which Could form the basis for developing additional defense against influenza pandemics.
The cAMP Receptor-Like Protein CLP Is a Novel c-di-GMP Receptor Linking Cell-Cell Signaling to Virulence Gene Expression in Xanthomonas campestris
(2010-02-26)
Chin, Ko-Hsin
;
Lee, Yen-Chung
;
Tu, Zhi-Le
;
Chen, Chih-Hua
;
Tseng, Yi-Hsiung
Cyclic-di-GMP [bis-(3'-5')-cyclic diguanosine monophosphate] controls a wide range of functions in eubacteria, yet little is known about the underlying regulatory mechanisms. In the plant pathogen Xanthomonas campestris, expression of a subset of virulence genes is regulated by c-di-GMP and also by the CAP (catabolite activation protein)-like protein XcCLP, a global regulator in the CRP/FNR superfamily. Here, we report structural and functional insights into the interplay between XcCLP and c-di-GMP in regulation of gene expression. XcCLP bound target promoter DNA with submicromolar affinity in the absence of any ligand. This DNA-binding capability was abrogated by c-di-GMP, which bound to XcCLP with micromolar affinity. The crystal structure of XcCLP showed that the protein adopted an intrinsically active conformation for DNA binding. Alteration of residues of XcCLP implicated in c-di-GMP binding through modeling studies caused a substantial reduction in binding affinity for the nucleotide and rendered DNA binding by these variant proteins insensitive to inhibition by c-di-GMP. Together, these findings reveal the structural mechanism behind a novel class of c-di-GMP effector proteins in the CRP/FNR superfamily and indicate that XcCLP regulates bacterial virulence gene expression in a manner negatively controlled by the c-di-GMP concentrations. (C) 2009 Elsevier Ltd. All rights reserved.
The Fable of Intermittent Images: On Jacques Ranciere's Theses of Film Aesthetics
(國立陽明交通大學出版社, 2010-03-01)
孫松榮
當代法國思想家賈克•洪希耶以電影的「矛盾寓言」導引出「藝術的再現體制」與「藝術的美學體制」之間共構與間隔的雙重關係。作為延續「藝術思想體制」的電影，其位階的曖昧性在於接續與發展其他藝術範型所共有的古典型態與內容的同時，將差異於再現性與敘事性詩學的純粹感性影像，或更準確而言，將「間隔性影像」體現出來。如此一來，洪希耶將指涉殊異表達性與創置理念模式的電影美學定義，和浪漫主義以降實踐美學變革的藝術範型聯繫在一起。對哲學家而言，這除了是「藝術認同體制」的共同指涉外，更是表徵運動音像的獨特性。本文以為在哲學家的電影美學論述中，「間隔性影像」不僅是敘事詩學與純粹感性共構的微型影像事件，也是錯位於導演作者創作理念的人形物質，更是透過影像潛在變動性對非人性的歷史詩學進行「後設感性」的「寓言」見證。換言之，作為「電影美學力量」的「間隔性影像」即在內在交織、潛在差異與越界移位的電影歷史經驗和「藝術認同體制」中，一方面展現了啟發當代電影分析與理論研究的實質作用；另一方面則是表徵了一種形式共構與重新劃分的挪用能量及勾畫出殊異世界輪廓的方略，並進一步形構思想感性模式的藝術理念。
Electrostatic interactions of arbitrarily dispersed multicoated elliptic cylinders
(2010-03-01)
Kuo, Hsin-Yi
;
土木工程學系
;
Department of Civil Engineering
We propose a theoretical framework for evaluation of electrostatic potentials in an unbounded isotropic matrix containing a number of arbitrarily dispersed elliptic cylinders subjected to a remotely prescribed potential field. The inclusions could be homogeneous or confocally multicoated, and may have different sizes, aspect ratios and different conductivities. The approach is based on a multipole expansion formalism, together with a construction of consistency conditions and translation operators. This procedure generalizes the approach of the classic work of Rayleigh [1] for a periodic array of circular disks or spheres to an arbitrarily dispersion of elliptic cylinders. We combine the methods of complex potentials with a re-expansion formulae and the generalized Rayleigh's formualtion to obtain a complete solution of the many-inclusion problem. We show that the coefficients of field expansions can be written in the form of an infinite set of linear algebraic equations. Numerical results are presented for several configuarions. We further apply the obtained field solutions to determine the effective conductivity of the composite. (C) 2009 Elsevier Ltd. All rights reserved.
On Reducing Test Power, Volume and Routing Cost by Chain Reordering and Test Compression Techniques
(2010-03-01)
Lin, Chia-Yi
;
Hsu, Li-Chung
;
Chen, Hung-Ming
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
With the advancement of VLSI manufacturing technology entire electronic systems can be Implemented in a single intergrated circuit Due to the complexity in SoC design. circuit testability becomes one of the most challenging works Without careful planning it Design For Testability (DFT) design, circuits consume mote power in test mode operation than that in normal functional mode This elevated testing power may cause problems including overall yield lost and instant circuit damage In this paper, we present two approaches to minimize scan based DFT power dissipation First methodology Includes routine cost consideration in scan chain reordering after cell placement. while second methodology provides test pattern compression for lower power We formulate the first problem as a Traveling Salesman Problem (TSP). with different cost evaluation from [18],[19] and apply an efficient heuristic to solve it lit the second problem we provide a selective scan chain architecture and perform a simple yet effective encoding scheme for lower scan testing power dissipation The experimental results of ISCAS'89 benchmarks show that the first methodology obtains up to 10% average power saving under the same low routing cost compared with a recent result in [19] The second methodology reduces over 17% of test power compared with filling all don't care (X) bit with 0 in one of ISCAS'89 benchmarks We also provide the integration flow of these two approaches in this paper
Pulsatile flows and wall-shear stresses in models simulating normal and stenosed aortic arches
(2010-03-01)
Huang, Rong Fung
;
Yang, Ten-Fang
;
Lan, Y. -K.
;
生物科技學系
;
Department of Biological Science and Technology
Pulsatile aqueous glycerol solution flows in the models simulating normal and stenosed human aortic arches are measured by means of particle image velocimetry. Three transparent models were used: normal, 25% stenosed, and 50% stenosed aortic arches. The Womersley parameter, Dean number, and time-averaged Reynolds number are 17.31, 725, and 1,081, respectively. The Reynolds numbers based on the peak velocities of the normal, 25% stenosed, and 50% stenosed aortic arches are 2,484, 3,456, and 3,931, respectively. The study presents the temporal/spatial evolution processes of the flow pattern, velocity distribution, and wall-shear stress during the systolic and diastolic phases. It is found that the flow pattern evolving in the central plane of normal and stenosed aortic arches exhibits (1) a separation bubble around the inner arch, (2) a recirculation vortex around the outer arch wall upstream of the junction of the brachiocephalic artery, (3) an accelerated main stream around the outer arch wall near the junctions of the left carotid and the left subclavian arteries, and (4) the vortices around the entrances of the three main branches. The study identifies and discusses the reasons for the flow physics' contribution to the formation of these features. The oscillating wall-shear stress distributions are closely related to the featured flow structures. On the outer wall of normal and slightly stenosed aortas, large wall-shear stresses appear in the regions upstream of the junction of the brachiocephalic artery as well as the corner near the junctions of the left carotid artery and the left subclavian artery. On the inner wall, the largest wall-shear stress appears in the region where the boundary layer separates.
Color Breakup Reduction by 180 Hz Stencil-FSC Method in Large-Sized Color Filter-Less LCDs
(2010-03-01)
Lin, Fang-Cheng
;
Huang, Yi-Pai
;
Shieh, Han-Ping David
;
光電工程學系
;
顯示科技研究所
Field-sequential color (FSC) is a high optical throughput technique for future green liquid crystal displays (LCDs). However, the FSC-LCD faces a lethal issue, color breakup (CBU) which degrades image clarity and prevents high level LCD-TV productions. We proposed the "180 Hz Stencil Field-Sequential-Color" method to redistribute intensities of the three primary color field-images to suppress CBU. By applying local color-backlight-dimming technology to FSC-LCDs, a low resolution colorful backlight panel combined with a high resolution color filter-less LC panel generated a "green-based multi-color" field-image which showed the most image luminance in the first field. Therefore, residual red and blue field-image intensities were reduced and effectively suppressed CBU when compared to field-rate increasing methods. In addition, to further implement hardware, the number of backlight divisions of 32 24 and a proper Gaussian point spread function profile were optimized via simulations while considering CBU reduction and image fidelity. Using optimized hardware parameters, the CBU phenomenon was suppressed by 50% of traditional RGB driving in simulation and was demonstrated on a 120 Hz 46-inch MVA LCD-TV.
光調制器與其所應用之光學多工／解多工器
(2010-03-01)
潘犀靈
;
趙如蘋
;
黃銘杰
;
藍玉屏
一種光學多工/解多工器，包括了分光元件和光調制單元。其中，分光元件用來將一主光束分成多道不同波長的子光束。然後這些子光束會分別對應入射到光調制單元上的其中一個畫素。而光調制單元則包括第一玻璃基板和第二玻璃基板，其中第一玻璃基板的第一側係接收對應之子光束，其第二側則與第二玻璃基板的第一側相對。第一玻璃基板的第二側上和第二玻璃基板的第一側上，都會形成電極和配向模。其中第一和第二玻璃基板上的電極係分別耦接驅動電壓和共同電壓。藉由控制驅動電壓，可以決定是否讓對應之子光束從第二玻璃基板的第二側出射。
Effect of strain relaxation of oxidation-treated SiGe epitaxial thin films and its nanomechanical characteristics
(2010-03-01)
He, Bo-Ching
;
Wen, Hua-Chiang
;
Chinag, Tun-Yuan
;
Chang, Zue-Chin
;
Lian, Derming
In this study, we examined the effect of high-temperature oxidation treatment on the SiGe epitaxial thin films deposited on Si substrates. The X-ray diffraction (XRD), atomic force microscopy (AFM), and nanoindentation techniques were employed to investigate the crystallographic structure, surface roughness, and hardness (H) of the SiGe thin films, respectively. The high-temperature oxidation treatment led to Ge pileup at the surface of the SiGe thin films. In addition, strain relaxation occurred through the propagation of misfit dislocations and could be observed through the cross-hatch pattern (800-900 degrees C) and SiGe islands (1000 degrees C) at the surface of the SiGe thin films. Subsequent hardness (H) measurement on the SiGe thin films by continuous penetration depth method indicated that the phenomenon of Ge pileup caused a slightly reduced H (below 50 nm penetration depth), while relaxation-induced defects caused an enhanced H (above 50 nm penetration depth). This reveals the influence of composition and defects on the structure strength of high-temperature oxidation-treated SiGe thin films. (C) 2009 Elsevier B.V. All rights reserved.
RANDOMIZED POLICY OF A POISSON INPUT QUEUE WITH J VACATIONS
(2010-03-01)
Ke, Jau-Chuan
;
Huang, Kai-Bin
;
Pearn, Wen Lea
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
This paper studies the operating characteristics of an M/G/1 queuing system with a randomized control policy and at most J vacations. After all the customers are served in the queue exhaustively, the server immediately takes at most J vacations repeatedly until at least N customers are waiting for service in the queue upon returning from a vacation. If the number of arrivals does not reach N by the end of the J(th) vacation, the server remains idle in the system until the number of arrivals in the queue reaches N. If the number of customers in the queue is exactly accumulated N since the server remains idle or returns from vacation, the server is activated for services with probability p and deactivated with probability (1-p). For such variant vacation model, other important system characteristics are derived, such as the expected number of customers, the expected length of the busy and idle period, and etc. Following the construction of the expected cost function per unit time, an efficient and fast procedure is developed for searching the joint optimum thresholds (N*, J*) that minimize the cost function. Some numerical examples are also presented.
Using An Interactive Approach to Finding Right Tutors on P2P Tutoring Grids
(2010-03-01)
Shih, Wen-Chung
;
Yang, Chao-Tung
;
Tseng, Shian-Shyong
;
Chu, Yianshu
;
資訊工程學系
The e-Tutors Project supported by MoE, Taiwan, provides remote tutoring service for pupils of rural areas. The preliminary result shows that the learning performance of students has been improved. However, for this service to further assist rural students, the goal of adaptive learning has to be considered in tutor assignment process. Hence, a P2P Tutoring Grid is proposed for the sharing of voluntary tutor resources. In this work, we formulate the tutor finding problem and propose an interactive and iterative heuristic method. The proposed approach consists of two phases: construction phase and search phase. In construction phase, peer information is acquired and managed in a decentralized manner. In search phase, the intention of a query is verified interactively and iteratively to find right tutors. A prototype system has been developed and experiments have been conducted to evaluate the performance of this approach. The experimental results show that the interactive algorithm performs well in peer-to-peer networks with low trust and availability. Also, a survey of satisfaction shows that the proposed method is more user-friendly.
回應子安宣邦的倫理思考
(國立陽明交通大學出版社, 2010-03-01)
劉紀蕙