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11.
Since brain tumors endanger people‘s living quality and even their lives, the accuracy of classification becomes more important. Conventional classifying techniques are used to deal with thosedatasets with characters and numbers. It is difficult, however, to apply them to datasets that include brain images and medical history (alphanumeric data), especially to guarantee the accuracy.For these datasets, this paper combines the knowledge of medical field and improves the traditional decision tree. The new classification algorithm with the direction of the medical knowledge not only adds the interaction with the doctors, but also enhances the quality of classification. The algorithm has been used on real brain CT images and a precious rule has been gained from the experiments. This oaoer shows that the ahzorithm works well for real CT data. 相似文献
12.
1IntroductionDehangisascenicspotlocatedatthesouthofWulingMTsintheCentralChil1a,between2815'and2843'N,lo93o'andlO945lE,risingfroml89.4mto964.6mabovesealevel,withanareaof225km.Thisre-gionhasacomplicatedtopography.Itissituatedinsubtropicmonsoonclimateareaandrichinlimestone.Ev-ergreebroad-leavedforest,Bambooforestandlowsimountainevergreenconiferousforestaremainvegeta-tionshere'Moreover,Miaonationalitypeoplehhvebeenlivinghereforalongtimeanditenjoysgreatnation-a1navour.Thenoraisrichandthevegeta… 相似文献
13.
Adaptive control of system with hysteresis using neural networks 总被引:1,自引:0,他引:1
Li Chuntao & Tan Yonghong . Coll. of Automation Nanjing Univ. Aeronautics Astronautics Nanjing P. R. China . Lab of Intelligent Systems Control Engineering Guilin Univ. of Electronic Technology Guilin P. R. China 《系统工程与电子技术(英文版)》2006,17(1):163-167
1.INTRODUCTIONThe piezoelectric actuators are well suited for micro-position devices in precision engineering because oftheir fast response,nanometer resolution and biggerdriving force[1].However,hysteresis inherent topiezoelectric actuator severely li mits system’s perfor-mance such as giving rise to undesirable accuracy oroscillations,even leading to instability.Hysteresischaracteristics are generally nondifferentiable andusually unknown.It is a difficult task to mitigate itsharmful ef… 相似文献
14.
Li Zhang & Fang Huajing . Dept. of Control Science Engineering Huazhong Univ. of Science Technology Wuhan P.R.China . Coll. of Physics Electronic Technology Hubei Univ. Wuhan P.R. China 《系统工程与电子技术(英文版)》2006,17(1):172-176
1.INTRODUCTIONAs a system becomes more and more intelligent andflexible,the systemrequires more sensors,actuators,and controllers,which are often referred to as fielddevices.In most cases,these field devices requiresome type of electrical connection because they aredistributed over a certain area.Conventionally thesedevices are connected with point-to-point connec-tions,whichis not suitable any more for modern in-dustrial control systems,because the number of cableis proportional tothe squ… 相似文献
15.
Chen Niansheng~ Li Layuan~ & Dong Wushi~ .School of Computer Science Wuhan Univ. of Technlogy Wuhan R. R. China .Dept.of Computer Science Hubei Normal Univ. Wuhan P. R. China 《系统工程与电子技术(英文版)》2006,17(3):642-647
1 .INTRODUCTIONA mobile Ad hoc network refers to a temporal multi-hop autonomy system,whichis constituted by a groupof mobile nodes containing wireless send-receive equip-ments[1].It possesses manycharacteristics-fast-deploy-able,self-organized,acentric , movable and of multi-hop.It can be wildly applied to many fields ,such asnational defense,emergency and disaster ,scientificin-vestigation and exploration etc .,and uponthat ,it hasgreat prospects[1 ,3 6]. With the wide spread of mo-bile… 相似文献
16.
TheQinghai TibetPlateauhasthehonorof“theroofoftheworld”.Comparingitwiththe NorthPoleandSouthPole,thegeoprapherscallithethirdpoleoftheglobe.Itnotonlycanbe calledthefirstintheworldintermsofthealtitude andarea,butalsotheyoungestplateauontheearth.TheQinghai TibetPlateauhastheunique naturallandscape,specialstructureofearthcrustandearthmantle,complicatedbiota,diversified ecosystemandabundantnaturalresources.Theshapingup,evolvingandexistingoftheplateau broughtwideanddeepeffectonitself,andalsoon… 相似文献
17.
LI Li DING Yaping WU Qingsheng 《科学通报(英文版)》2006,51(7):791-795
Group II-VI semiconductors, because of its wider band width and nonlinear optical properties, have al- ready shown vital applications in fluorescence probe, sensors, solar battery, photoelectrocatalysis, photoelec- tricity devices, laser light-emitting di… 相似文献
18.
中国北方表土微团粒粒度分布及其对粉尘 总被引:4,自引:1,他引:4
利用干筛筛析法测定了中国北方沙漠、戈壁、绿洲、干草原农垦区和草原牧区等代表性表土(沙质土、砾质沙土、砾质壤土、壤土和粉壤土等)的微团粒粒度分布. 组成表土微团粒粒度分布的对数正态群体分别为粉细沙、细沙、中沙、粗沙和极粗沙群体, 其平均的质量中值粒径分别为90, 210, 390, 600和980 mm, 平均的标准偏差分别为1.25, 1.40, 1.25, 1.35和1.25. 粉细沙、细沙、中沙、粗沙、砾质沙、砾质壤土、壤土等表土类型的微团粒粒度分布为这几个对数正态分布群体中的组合. 粉尘释放模型(DPM模型)模拟的结果显示: 表土微团粒粒度分布对粉尘释放通量存在显著影响, 细沙和粉细沙的粉尘释放通量最大, 中沙、砾质沙、砾质壤土、壤土、粉壤土次之, 粗沙的粉尘通量最小, 差值范围在101~103 mg·m-2·s-1左右; 中国北方沙漠(沙地)和片状流沙覆盖的农田的粉尘释放通量在101~104 mg· m-2·s-1之间, 而沙砾质戈壁、沙砾质化的农田和草原的粉尘释放通量在101~102 mg·m-2·s-1之间, 表明中国北方沙漠(沙地)和片状流沙覆盖的农田是粉尘释放的主要源地. 相似文献
19.
20.
Poly(dimethylsiloxane) based microchip for DNA electrophoresis 总被引:2,自引:0,他引:2
A novel poly(dimethylsiloxane)(PDMS) -based microchip for DNA separation through electrophoresis has been developed using a micro-electro-mechanical-system(MEMS) technology. Unlike previous hybrid PDMS microchip, one PDMS film is first created on glass support by pressing method in our microchip. Thus, increased band-broadening phenomena, arising from the material nonuniformity at the walls of microchannel, can be avoided in electrophoresis process. A low-viscosity hydroxypropylmethylcellulose-100 (HPMC-100) is used as the separation medium for fluorescent intercalator-labeled double-stranded DNA (dsDNA) fragments. Mannitol is introduced to PDMS-based microchip as a separation medium additive to enhance separation efficiency. At applied electric field strength of 150 V/cm, excellent separations of the PCR marker could be achieved with an effective separation distance of 25mm . 相似文献