ENHANCING LEFT-VENTRICULAR SHORT-AXIS ECHOCARDIOGRAPHIC CINELOOPS WITH A PULSE COUPLED NEURAL NETWORK
James Wolfer?James Roberg′e?Jeffrey Soble?
ABSTRACT
Observing the motion of endocardial borders in echocar-diographic cineloops is an important component for both the qualitative and quantitative analysis of regional left ventricular function.Consequently,using the computer to enhance endocardial border pixels is an important?rst step both for annotating and eventual computer analy-sis of echocardiograms.Previous work has demonstrated the viability of pulse coupled neural networks for enhanc-ing echocardiograms acquired using an acoustical contrast agent.In this study we investigate using pulse coupled neu-ral networks as a visualization tool,highlighting,frame-by-frame,the endocardial border in left-ventricular short-axis cineloops.
Index Terms
Computer Vision,Medicine,Health,Echocardiology,Neu-ral Networks,AI
Introduction
The detection of potential border pixels is an important step in many computer vision applications,including the analysis of echocardiographic images.Similarly,the as-sessment of many diseases of the heart center around the morphology of the left ventricle over time[1].Identifying the myocardial-blood pool border,or endocardial border,is one important step toward assessing the contractile pattern of the myocardium.Unfortunately,echocardiogram im-ages often present challenges to computer vision systems due to low contrast and noise.
Many approaches to isolating the endocardial border have been described.Typically they include low level im-age processing,noise reduction,and edge detection.Exam-ples of this processing include the popular Soble and Canny edge detectors.
Post-processing is also used to identify edges and re-gions.Post-processing often incorporates information to form models such as active shapes and contours,and math-ematical morphology[2].
?Indiana University South Bend,South Bend,IN,USA,email: jwolfer@https://www.doczj.com/doc/b213283912.html,
?Cyberpulse L.L.C.,Highland Park,IL,USA
?Rush Medical Center,Chicago,IL USA,Jeffrey S Soble@https://www.doczj.com/doc/b213283912.html,
Pulsed Coupled Neural Networks Recently there has been enhanced interest in biologically inspired models of computation.These range from ge-netic algorithms to models of the immune system.Of these models,arti?cial neural networks have enjoyed the most exposure in applications.Examples in echocardiology in-clude LV shape recovery[3]and LV contour detection[4]. These neural networks are engineering metaphors inspired by contemporary models of neural interactions,and are not models of any speci?c biological process.For example, the popular multi-layered perceptron encodes information based upon the average?ring rate of these abstract neurons, ignoring the temporal relationships between the individual neurons.
In contrast,the Pulse Coupled Neural Network (PCNN)attempts to model neuron interactions in time. Based upon the work of Eckhorn[5,6]modeling interac-tions in the visual cortex of the cat,and more recently,pri-mates,the PCNN forms a high order network which pulses through time forming a succession of binary pulses.When the input is an image,this results in a series of binary im-ages.Attractive aspects of the PCNN for echocardiology include relative immunity to translation,scale,and rota-tion in the image[7].Imaging applications of pulse-coupled neural networks include contrast echocardiology[8],im-age shadow removal[9],and digital mammogram segmen-tation[10].
Figure1shows a schematic diagram of a single PCNN neuron.It is divided into three primary functions: feeding,linking,and pulse generation.This PCNN neuron is modeled by the following equations[7,11]:
F ij(t)=e?αFδt F ij(t?1)+S ij+V F kl W ijkl Y kl(t?1) L ij(t)=e?αLδt L ij(t?1)+V L kl M ijkl Y kl(t?1)
U ij(t)=F ij(t)(1+βL ij(t))
Y ij(t)= 1if U ij(t)>Θij(t)
0Otherwise
Θij(t)=e?αΘ?tΘij(t?1)+VΘY ij(t) Where F is the feeding component,L the linking component,U the neuron internal activity,Y the neuron output,andΘthe dynamic threshold.M and W represent encode weights from the individual inputs in the receptive ?eld for the feeding and linking functions respectively,and
? 2006 EHWC July 16 - 19, 2006, Santos, BRAZIL
Y (t ?1)
Step Function
Feeding Input Figure 1.PCNN Schematic
βis the linking strength.These equations are applied in sequence at each iteration of the simulation.
In image processing,an individual neuron receives in-put to its feeding function from a single,scaled,gray level pixel in the original image along with a receptive ?eld con-sisting of a weighted neighborhood.This results in one ar-ti?cial neuron being directly stimulated by a corresponding pixel and its neighbors from the input image,preserving the geometric structure of the image.
Assuming that the threshold is initially set to zero,any activity at the input will cause a corresponding output from the pulse generation.This,in turn,raises the thresh-old suppressing subsequent output.As the threshold de-cays neurons with activity exceeding the threshold pulse,reestablishing a high threshold for them,but also raising the probability that adjacent neurons will be ?re at the next iteration as a result of the linking feedback to the recep-tive ?eld.In this sense each arti?cial neuron can be seen as initiating an autowave of activity which propagates until colliding with another wavefront.
Figure 2illustrates the action of the PCNN when stim-ulated by the ?rst frame in the short-axis cineloop shown in Figure 3.For this,and all subsequent images,alpha was empirically ?xed at 10.0,1.0,and 15.0for the feeding,link-ing,and threshold computations respectively,and beta was 0.1.
Initially,at iteration one,every non-zero pixel causes the PCNN to ?re driving the threshold high as indicated by the entirely white image.Over time the threshold decays until neurons connected to those pixels providing the high-est stimulation ?re,in this case at iteration seventeen.This,in turn,stimulates the surrounding pixels causing them to ?re if they are close to their respective thresholds.
Application
Software to simulate the PCNN was written in Python,and then applied to the left-ventricular short-axis cineloop for a healthy canine.For each frame processed,the program reads the frame and represents the pixels as ?oating point values between zero and one.The resulting image forms the input to the feeding function of the PCNN.
As described,the PCNN produces a sequence of bi-nary images representing the neuron ?ring pattern at each iteration.Consistent with other work[8],we include user interaction to identify the iteration at which the best ?t to the data occurs.Speci?cally:
1.The user selects a prototype frame from the original cineloop.
2.The PCNN is applied to the selected frame producing a time-series of binary images representing the activ-ity at each iteration.
3.The user selects the iteration at which the PCNN pro-duces the best visual ?t to the desired image features.
4.The PCNN is applied to all frames in the original cineloop,with activity at the selected iteration de?n-ing the image enhancement.Again referring to Figure 2,we note that iteration eighteen forms the best visual ?t.The PCNN is then ap-plied to each frame in the cineloop,with its output at the selected iteration overlayed on the source frame,forming a new image sequence.Figure 4shows a sequence of original cineloop frames and 5shows the annotated frames.Note that the corresponding highlights,or annotations,track the
(a)Iteration 00(b)Iteration 15(c)Iteration 16(d)Iteration 17
(e)Iteration 18(f)Iteration 19(g)Iteration 20(h)Iteration21
Figure2.PCNN Iterations
(a)Feeding Input(b)Resulting Border
Figure3.Sample Cineloop Frame and Corresponding PCNN Enhancement
tissue borders as the ventricular morphology changes with contraction.
To further illustrate the applicability of this approach, we demonstrate it using an ischemic cineloop sequence. Figure6shows a series of ischemic cineloop frames.Again the user selects the best-?t iteration for the PCNN,which is then applied to each frame of the loop.The result is illustrated in Figure7.While not apparent in the printed images,this sequence contains many more noise artifacts, making the border-tracking more dif?cult.In this case ad-ditional image pre-processing,such as low-pass?ltering, could be useful but we elected to work with the unpro-cessed cineloop to demonstrate the PCNN response in a rel-atively harsh environment.Note that,while there are more artifacts,the PCNN still manages to track the endocardial border of the ischemic myocardium through the contraction cycle.
Summary
There are,in addition to its direct application,other po-tential applications for this cineloop enhancement.De-rived images,such as PCNN border-enhanced Synthetic M-mode images[12,13]could augment regional wall motion studies,for example.We would also like investigate its po-tential in a hybrid solution to border enhancement with ac-tive contours.It should be noted that the images presented here represent scan-converted gray-scale data.We would like to extend our investigation to consider the raw radio frequency data from the machine.Finally,our initial stud-ies lead us to believe that pulse coupled neural networks hold promise for the automated enhancement of left ven-tricular endocardial borders.Ultimately,this could lead to computer-assisted,quantitative assessment left ventricular function in clinical practice.
(a)Frame 04(b)Frame 05(c)Frame 06(d)Frame 07
(e)Frame 08(f)Frame 09(g)Frame 10(h)Frame11
Figure4.Cineloop Frames
(a)Frame 04(b)Frame 05(c)Frame 06(d)Frame 07
(e)Frame 08(f)Frame 09(g)Frame 10(h)Frame11
Figure5.Processed Cineloop Frames
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(a)Frame 06(b)Frame 07(c)Frame 08(d)Frame 09
(e)Frame 10(f)Frame 11(g)Frame 12(h)Frame13
Figure6.Ischemic Cineloop Frames
(a)Frame 06(b)Frame 07(c)Frame 08(d)Frame 09
(e)Frame 10(f)Frame 11(g)Frame 12(h)Frame13
Figure7.Processed Ischemic Frames
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SPE 132990 Petrophysical Evaluation for Enhancing Hydraulic Stimulation in Horizontal Shale Gas Wells Dan Buller, Simon Hughes, Jennifer Market, and Erik Petre, Halliburton, and David Spain and Tobi Odumosu, BP America Copyright 2010, Society of Petroleum Engineers This paper was prepared for presentation at the SPE Annual Technical Conference and Exhibition held in Florence, Italy, 19–22 September 2010. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright. Abstract The economic recovery of gas from shale reservoirs requires optimal multistage hydraulic stimulation in horizontal wells. Important parameters to consider in shale-gas evaluation include gas-filled porosity and total organic content. Mechanical rock properties, including a calculated brittleness index, along with mineralogy, are also required to target and design individual horizontal fracture stages in the best zones. This type of formation evaluation in horizontal wells requires careful correlation and calibration to petrophysical measurements obtained in either vertical pilot holes or direct offset wells. This paper presents a comprehensive approach to the evaluation of an unconventional resource play drilled in the Haynesville Shale in east Texas. Using openhole and logging-while-drilling (LWD) logs, conventional core analysis, and a chemostratigraphy analysis of drill cuttings, a shale analysis linking mineralogy, free gas, effective porosity, a shale brittleness index, and a clay linked transverse anisotropy is verified on separate vertical and horizontal control wells. Beyond that, pulsed neutron spectroscopy logs were run to develop a cased-hole evaluation solution from N-N (neural network) modeling that could replicate openhole wireline or LWD logs, and chemostratigraphy mineralogy results. Subsequently, two horizontal wells were logged with LWD tools and afterward, through casing, using the pulsed neutron log and neural network calibration. Fracture stages for the logged horizontal wells were then evaluated vs. the log data. Generally, lower normalized treating pressures per fracture stage are noted where lower clay volumes exhibit less transverse anisotropy and a higher calculated shale brittleness index. Radioactive tracer and production log data also confirm lower amounts of gas production from zones that are apparently fractured, but are more ductile and clay-rich. Introduction The Haynesville Shale is a black, organic-rich, shale that covers Caddo, Bossier, De Soto, Red River, and Bienville parishes in north Louisiana and primarily Harrison, Panola, Shelby, and San Augustine counties in east Texas The depth ranges from approximately 10,300 ft in the northwest part of the play to approximately 14,000 ft in the southeast. The Bossier Shale lies above the Haynesville Shale; the Haynesville Lime or Smackover Lime lie below it throughout the area. Both of these formations can be drilling targets, but the Haynesville Shale is of special interest because of generally thicker net pay and higher reservoir pressure with a gradient between 0.85 and 0.9 psi/ft. Varying depositional environments have left the shale with a thickness that varies between 80 and 350 ft, and facies that varies between a calcite-rich shale with little clay to a silica-rich shale with large amounts of bedded clay and lesser amounts of calcite (Parker et al. 2009). Advanced evaluation suites can provide an abundance of reservoir information. The primary purpose is resource identification and a calculation of original gas in place. However, new formation analysis and presentation techniques are required for a comprehensive mechanical description of this shale to select an optimum horizontal target (Rickman et al. 2008; Mullen et al. 2007). Subsequently, the same type of information can be used to select and design optimum fracture stages along the horizontal well. Currently, a few operators are beginning to log their horizontal wells, but are not using any log data to strategically locate or plan the horizontal fractures. The current completion practice is still evolutionary because more fracture stages per lateral have achieved better results as more surface area is contacted. Perforation clusters and spacing per fracture stage have been increased or decreased, depending on whether at the location or on the operator. The one constant is that fracture treating pressures and rates, depending on job design, all indicate serious stratigraphic formation differences that must be accounted for. Post-fracture
Figure 2. Amplification of a fragment of the human retinoblastoma gene with additives DMSO and
Figure 4. NMR analyses of betaine and two commercial PCR additives. Panel A
and specificity of PCR amplifications, their effects on the melting temperature of DNA may alter the optimal annealing conditions for a particular reaction. Therefore, it may be necessary to empirically determine the optimal annealing temperature if adding one or both of these agents to a particular amplification reaction. R EFERENCES 1.Sarkar, G., Kapelner, S. and Sommer, S.S. (1990) Nucl. Acids Res. 18, 7465. 2. Varadaraj, K. and Skinner, D.M. (1994) Gene 140, 1. 3.Baskaran, N. et al. (1996) Genome Res. 6, 633. 4.Weissensteiner, T. and Lanchbury, J.S. (1996) BioTechniques 21, 1102. 5. Hengen, P.N. (1997) Trends Bioch. Sci. 22, 225. 6.Henke, W. et al. (1997) Nucl. Acids Res. 25, 3957. 7.Melchior, W.B., Jr., and von Hippel, P.H. (1973) Proc. Natl. Acad. Sci. USA 70, 298. 8.Rees, W.A. et al. (1993) Biochemistry 32, 137. 9. Bookstein, R. et al. (1990) Nucl. Acids Res. 18, 1666. 10. PCR Handbook for Taq DNA polymerase and Taq PCR Core Kit (1996) Qiagen. 11.Advantage-GC TM cDNA PCR User Manual P3091-1 (1997) CLONTECH. ? 1998 Promega Corporation. All Rights Reserved. Advantage-GC is a trademark of CLONTECH Laboratories, Inc. Aldrich is a registered trademark of Aldrich Chemical Co. Perkin-Elmer is a registered trademark of The Perkin-Elmer Corporation. Triton is a registered trademark of Union Carbide Chemicals and Plastics Co., Inc. pGEM is a trademark of Promega Corporation and is registered with the U.S. Patent and Trademark Office. Product claims are subject to change. Please contact Promega Technical Services or access the Promega online catalog for the most up-to-date information on Promega products. Related Products Product Size Cat.#PCR Core System I 200 reactions M7660PCR Core System II 200 reactions M7665
Enhancing Production of Bio-Isoprene Using Hybrid MVA Pathway and Isoprene Synthase in E.coli Jianming Yang1,Mo Xian1*,Sizheng Su2,Guang Zhao1,Qingjuan Nie3,Xinglin Jiang1,Yanning Zheng1, Wei Liu1 1Biomaterials Center,Qingdao Institute of Bioenergy and Bioprocess Technology,Chinese Academy of Sciences,Qingdao,China,2Department of Biochemistry,Beijing Risun Chemical Technologies Institute,China Risun Coal Chemicals Group Limited,Beijing,China,3College English Office,Foreign Languages School,Qingdao Agricultural University,Qingdao,China Abstract The depleting petroleum reserve,increasingly severe energy crisis,and global climate change are reigniting enthusiasm for seeking sustainable technologies to replace petroleum as a source of fuel and chemicals.In this paper,the efficiency of the MVA pathway on isoprene production has been improved as follows:firstly,in order to increase MVA production,the source of the‘‘upper pathway’’which contains HMG-CoA synthase,acetyl-CoA acetyltransferase and HMG-CoA reductase to covert acetyl-CoA into MVA has been changed from Saccharomyces cerevisiae to Enterococcus faecalis;secondly,to further enhance the production of MVA and isoprene,a alanine110of the mvaS gene has been mutated to a glycine.The final genetic strain YJM25containing the optimized MVA pathway and isoprene synthase from Populus alba can accumulate isoprene up to 6.3g/L after40h of fed-batch cultivation. Citation:Yang J,Xian M,Su S,Zhao G,Nie Q,et al.(2012)Enhancing Production of Bio-Isoprene Using Hybrid MVA Pathway and Isoprene Synthase in E.coli.PLoS ONE7(4):e33509.doi:10.1371/journal.pone.0033509 Editor:Spencer J.Williams,University of Melbourne,Australia Received December5,2011;Accepted February15,2012;Published April27,2012 Copyright:?2012Yang et al.This is an open-access article distributed under the terms of the Creative Commons Attribution License,which permits unrestricted use,distribution,and reproduction in any medium,provided the original author and source are credited. Funding:No funding has supported the work. Competing Interests:Sizheng Su is currently employed by China Risun Coal Chemicals Group Limited.There are no other relevant declarations relating to employment,consultancy,patents,products in development or marketed products for Sizheng Su or any other authors.This does not alter the authors’adherence to all the PLoS ONE policies on sharing data and materials. *E-mail:xianmo@https://www.doczj.com/doc/b213283912.html, Introduction Isoprene(2-methyl-1,3-butadiene)was firstly discovered as a cell metabolite in the mid-1950s by Sanadze.[1,2].It functions as a thermoprotectant of plant membranes or as an antioxidant[3,4], or may have a signaling function,altering the flowering time in some plants[5].As an important platform chemical,isoprene has been used in industrial production of synthetic rubber for tires and coatings[6]or aviation fuel[7]. Isoprene is the progenitor of the isoprenoid family of compounds[8].Many commercially relevant isoprenoids exist in nature in small quantity and the yield produced from their natural organisms remains rather low.The depletion of fossil sources and the structural complexity of isoprenoids make it difficult or costly to produce isoprenoids by means of chemical synthesis.Isoprene is no exception since it is produced entirely from petrochemical sources through chemical synthesis method[9,10,11]. Compared with conventional means,microbial synthesis of isoprene by fermentation should become a promising and attractive route mainly for environmental production,renewable resources,sustainable development[12].Additionally,isoprene could be collected from the gas phase of the fermentor,eliminating the need for distillation.All isoprenoids are biosynthesized from the same basic units,isopentenyl diphosphate(pyrophosphate; IPP),and its isomer dimethylallyl diphosphate(DMAPP),which are synthesized from two different pathways including methyler-ythritol4-phosphate(MEP)pathway and mevalonate(MVA) pathway(Fig.1)[13].MVA pathway mainly exists in eukaryotes,archaebacteria,and cytosols of higher plants,while the MEP pathway is used by many eubacteria,green algae,and chloroplasts of higher plant[14,15].MVA pathway has been studied extensively for producing isoprenoids.The introduction of heterologous MVA pathway genes into E.coli has been reported to improve the productivity of carotenoids or sesquiterpenes that are synthesized from DMAPP[16,17,18,19,20,21,22]. Although MVA pathway has been studied comprehensively,the methylerythritol phosphate(MEP)pathway was merely discovered in the early1990s by labeling experiments in bacteria and plants[23,24],and till2001the genes of whole MEP pathway has been completely characterized[25].This biosynthetic pathway, made up of seven enzymatic steps,begins with the condensation of pyruvate and glyceraldehyde-3-phosphate to form1-deoxy-D-xylulose5-phosphate(DXP)and ends with the formation of the isoprenoid precursors isopentenyl diphosphate(IPP)and dimethy-lallyl diphosphate(DMAPP)[26,27].In spite of great efforts taken in isoprenoids production using MEP pathway[28,29,30],this approach still remains ineffective due to regulation mechanisms present in the native host[18]. In this paper,based on our previous experiments,the efficiency of the MVA pathway on isoprene production has largely been improved as follows:firstly,in order to increase MVA production, the source of the‘‘upper pathway’’which contains HMG-CoA synthase,acetyl-CoA acetyltransferase and HMG-CoA reductase to covert acetyl-CoA into MVA has been changed from Saccharomyces cerevisiae to Enterococcus faecalis;secondly,to further enhance the production of MVA and isoprene,a alanine110of
Enhancing the Taste of Our Food A What are your favorite foods? Do you like pizza, hamburgers, roast pork, or sweet cakes and cookies? Chances are that, whatever you like best, it has a strong taste and a salty, sweet or savory flavor. People generally like to eat tasty foods, and this can create potential health problems, especially with the consumption of fast or processed food. Fast food traditionally contain a lot of salt or sugar, because this is a cheap way to make food taste good and it encourages people to buy more cookies, chips and soft drinks, for example. However, people are becoming increasingly aware of the dangers of an unhealthy diet, and the manufacturers of processed food know that sales will increase if they can advertise that their products have less salt or sugar. They also know that if their product tastes bland or boring, no amount of health benefits will make it a popular choice with consumers, and they will lose money if their product is not popular. However, a new technology is currently being developed that may allow fast food manufacturers to reduce salt and sugar without sacrificing taste. B If you stick out your tongue and look in the mirror, you will see that it is covered with tiny bumps. These bumps are called taste buds and they are the receptors in your skin that allow us to taste different kinds of foods. There are five different taste receptors, for sweet, salty, sour, bitter and savory flavors. When we are born we have a lot of these on the roof of our mouth as well as on our tongue, but as we get older, we lose taste buds, which is why older people find it harder to taste things. Adults typically have about 10,000 taste buds, but older people may have as few as 5,000. We have more receptors for bitter tastes than for any others; researchers think that this may be because these taste buds warn us if food is poisonous. C The food that we eat contains natural chemicals that fit into the different shaped receptors on our tongues; for example, sweet foods trigger the sweet receptors. The technology to mimic, or copy, these natural flavors with chemicals such as aspartame is a common ingredient in many diet soft drinks and other diet products. While aspartame allows us to experience a sweet taste without eating sugar, it also has disadvantages. Firstly, many people do not like its bitter aftertaste, and secondly, some people say that it is bad for health if taken in large quantities. D However, a new technology is being developed that may be an improvement on artificial sweeteners and other chemicals. Taste enhancers target the taste receptors on our tongues and they make us more sensitive to sweet, sour or salty tastes. Just a few molecules of a taste enhancer could double the sweetness effect of a teaspoon of sugar, or the salty effect of a teaspoon of salt. This means that instead of using artificial chemicals to make food tasty, food manufacturers could use half the quantity of the real substance and a tiny quantity of taste enhancer to make the food taste good. This has the potential to save food manufacturers money, by replacing large quantities of sugar and salt with tiny amounts of chemicals. It could also benefit our health if we can eat food that tastes good and is low in sugar and salt.
英语知识运用对词汇的考查要求考生能够准确掌握词义、短语和固定搭配的用法。 ●例如1997年第45～47题 44 its economy continues to recover，the US is increasingly becoming a nation of part timers and temporary workers. This “45” work force is the most important 46in American business today，and it is 47changing the relationship between people and their jobs. 44.[A]Even though[B]Now that[C]If only[D]Provided that 45.[A]durable[B]disposable[C]available[D]transferable 46.[A]approach[B]flow[C]fashion[D]trend 47.[A]instantly[B]reversely[C]fundamentally[D]sufficiently 45题考查的是形容词的辨析。解答这类题主要看被修饰的成分。本题中被修饰的名词是work force，在本文指临时工。四个选项中描述临时工最大特点的选项即为正确答案。符合文意的只有disposable（可随时抛弃的）。 46题考查的是名词的词义辨析。表示政治、经济、社会发展等“趋势”的词为trend. 47题考查副词的词义辨析和使用。解这类题还是要看副词所修饰的成分：二者是否搭配合理，是否与文章主线有关。sufficiently与所修饰部分不能搭配，而instantly，reversely与所修饰部分构成搭配后与文章主线无关。因而，只有fundamentally符合题意。 1）词义的辨析和使用中的几个误区 从近几年考生答题的情况看，在词义辨析和使用中存在的几个误区：一是只知其一，不知其它。英语的很多词汇都是多义词，而词汇辨析往往考词的多重意义。二是只知大概，不知具体。只知道词的大致含义，不知道它具体的解释。三是只知认词，不知辨词。四是只知词义，不知使用。五是用中文的思维，替代英文词的词义。 在应试准备中，考生应该： ★熟练掌握大纲所要求掌握的词汇； ★熟悉词语的用法和词语搭配； ★注意词语的引申词，即同根词，同义词，反义词，近义词等； ★复习并熟练掌握语法知识； ★大量广泛地阅读以扩大词汇量和知识面；
1877-0428 ? 2010 Published by Elsevier Ltd.doi:10.1016/j.sbspro.2010.03.191 Procedia Social and Behavioral Sciences 2 (2010) 1305–1309 Available online at https://www.doczj.com/doc/b213283912.html, WCES-2010 Enhancing the development of speaking skills for non-native speakers of English Kamonpan Boonkit a * a Faculty of Arts, Silpakorn University, Nakhon Pathom, 73000, Thailand Received October 12, 2009; revised December 21, 2009; accepted January 6, 2010 Abstract Speaking is one of the four macro skills to be developed as a means of effective communication in both first and second language learning contexts. In the English as a Foreign Language (EFL) pedagogy environment, how to increase speaking competence and confidence for undergraduate students tends to be a crucial question among instructors. This concern led to a qualitative research design as an action study in a regular course employing a task-based approach. The findings indicated that confidence, creativity of topics, and speaking competence were the key aspects of improvement when speaking to the audience. ? 2010 Elsevier Ltd. All rights reserved. Keywords: English speaking development; factors enhancing EFL/ESL speaking skills. 1. Introduction Speaking is one of the four macro skills necessary for effective communication in any language, particularly when speakers are not using their mother tongue. As English is universally used as a means of communication, especially in the internet world, English speaking skills should be developed along with the other skills so that these integrated skills will enhance communication achievement both with native speakers of English and other members of the international community. Because of the significant role of speaking in action, Bailey (2005) and Goh (2007) detailed how to enhance the development of speaking by means of syllabus design, principles of teaching, types of tasks and materials, and speaking assessment. In the Thai context of learning English as a Foreign Language (EFL), instructors regularly ask the question why the majority of undergraduate students are unable to speak English confidently, especially for communication in real situations with international speakers. One among many reasons to take into consideration might be a lack of confidence in terms of anxiety about making errors as stated by Trent (2009) and in other related studies. Basically, most Thai undergraduate students have studied English for approximately 8-10 years before entering the tertiary level. Based on the question of how to increase the speaking confidence and competence of undergraduate students, an initial informal interview was conducted with a group of EFL university students on the factors expected to enhance their speaking skills. Development of confidence and occasions to speak were among the key responses * Kamonpan Boonkit. Tel.: +66-86-573-6368; fax: +66-34-255-794 E-mail address : kamonpan@su.ac.th