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⊙第101篇⊙

基于自由曲面點云的快速原型制作技術研究
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注意:本論文已在《機械工程學報》2003,39(1):56-59,83發表
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孫玉文 賈振元
(大連理工大學現代制造技術研究所大連1 16024)
王越超 劉偉軍
(中國科學院機器人學開放研究實驗室)

摘 要: 針對不附加任何拓撲和幾何信息的云狀數據三維重建問題,提出了對點云直接進行分層處理快速制作原型的新方法。在對點集進行空間結構劃分的基礎上,采用最小距離關聯點對方法提取層面輪廓線數據,并對其加以勻化和精整從而直接生成快速成形機的層片接口文件,避免了常規方法存在的耗時和需要很高的造型技巧等不足,而且片面的錯誤校驗與修補等繁瑣工作也將不再進行,提高了快速成形前處理的效率,非常適合分層實體制造(LOM)等成形工藝。
關鍵詞: 反求工程 點云數據 直接分層 快速原型技術

RAPID PROTOTYPING MANUFACTURING BASED ON CLOUD DATA FROM FREE-FORM SURFACE

SunYuwen Jin Zhenyuan
(Dalian University ofTechnology)
Wang Yuechao Liu Weijun
(Robotics Laboratory,Chinese Academy ofScience)

Abstract: Physical model recovered from cloud dada only with coordinate information is of great importance in the integration of reverse engineering and rapid prototyping technology. A new method, that rapidly generates prototype from sampled points, is proposed. Based on establishing the spatial partitioning representation of point cloud, the contour data in each layer is firstly calculated and sequenced, then amended to generate exact slice file. It overcomes lots of drawbacks in traditional integration such as consuming time and needing expert modeling skills. Moreover, without the intermediate transactions of STL file, the work of checking and repairing mistakes of facets is avoided. It is very suitable for laminated object manufacturing and greatly improves the pretreatment efficiency of RP technology.
Keywords: Reverse engineering; Data cloud; Direct slicing; Rapid prototyping


⊙第102篇⊙

基于矢量分析的數控加工軌跡設計方法研究
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注意:本論文已在《機械工程學報》2005,41(3):160-164,170發表
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孫玉文 束長林 劉健
(大連理工大學精密與特種加工教育部重點實驗室大連116023)

摘 要: 描述了基于矢量分析和NURBS的數控加工軌跡設計方法。基于給定的被加工曲面在其參數域上的優化走刀方向集合,并依據標量場與梯度場的轉化關系,建立了精確逼近離散方向矢量的走刀矢量場擬合模型,由此給出了數控加工軌跡的矢量表達形式。以NURBS作為發生矢量場的流函數并借助其較強的局部調控能力,通過調整控制點列,可望實現數控加工軌跡拓撲形狀的整體優化調控。驗證實例表明該方法能夠進行復雜形狀數控加工軌跡的精細設計,有利于保證精度指標下曲面加工效率的最大化。
關鍵詞: 加工軌跡 矢量場 NURBS

VECTOR ANALYSIS BASED TOOLPATH GENERATION FOR PRECISION SURFACE MACHINING

Sun Yuwen Shu Changlin Liu Jian
(Key Laboratory for Precision & Non-traditional Machining ofMinistry of Education, Dalian University of Technology, Dalian 116023)

Abstract:A toolpath generation method is presented for NC machining based on vector analysis and NURBS. Given optimal cutting directions at sampled points in the parameter domain of the NURBS surface, a vector field model fitting to these scattered vectors is established according to the conversion between scalar field and gradient field. Thus, tool paths inthe parameter domain can be represented as vector curves of a 2D vector field. Moreover, using NURBS as the stream function of generating gradient field, a global shape optimization of tool-paths can be easily completed by adjusting the control point array of the stream function. The example shows that theprecise design method of tool paths is very useful in high- efficiency machining of complex shapes.
Keywords: Tool paths; Vector field; NURBS


⊙第103篇⊙

中國生物質燃料乙醇項目能量生產效率評估
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注意:本論文已在《農業工程學報》2005,21(11):121-123發表
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EI 已經收錄本文)
戴杜1,劉榮厚2,浦耿強1,王成燾1
(1上海交通大學機械與動力工程學院,上海 200030;
2上海交通大學農業與生物學院,上海 201101)

摘 要:為了對玉米和木薯乙醇的能量和可再生能量生產效率進行評估,該文統計了玉米和木薯乙醇生命周期能耗,并用市場價值量法按照主副產品的能耗進行了分配。計算出玉米和木薯燃料乙醇的凈能量和凈可再生能量。并計算了單產和化肥用量變化時的凈能量和凈可再生能量的變化。計算結果顯示,玉米、木薯乙醇的凈能量分別為1.472 MJ/L和2.417 MJ/L,凈可再生能量分別為1.474 MJ/L和2.459 MJ/L。使用玉米、木薯生產燃料乙醇在能量生產和再生能量生產上都是可行的,木薯乙醇比玉米乙醇可行性更高,單產和化肥用量是提高能源利用和再生能源的關鍵因素,加強副產品的開發和使用有機肥代替化肥有利于提高系統的能效,提高系統的可再生性。
關鍵詞:燃料乙醇;凈能量;可再生能源
中圖分類號:S216.2 文獻標示碼:A

Evaluation on Energy Production Efficiency of Biomass based Fuel Ethanol Program
Dai Du1, Liu Ronghou2, Pu Gengqiang1, Wang Chengtao1
(1 School of Mechanical and Power Engineering, Shanghai Jiaotong University, Shanghai 200030, China; 2 School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 201101, China)

Abstract: To assess corn and cassava fuel ethanol production energy efficiency, this paper estimates life cycle energy consumption of corn and cassava fuel ethanol, allocates energy uses between fuel ethanol and its byproducts, and finally, works out net energy value (NEV) and net renewable energy (NREV). It also gives NEV and NREV results of corn and cassava under changed yields and chemicals uses. The results show that NEV of corn and cassava ethanol are 1.472 MJ/L and 2.417 MJ/L, respectively, and NREV of corn and cassava ethanol are 1.474 MJ/L and 2.459 MJ/L, respectively. Corn and cassava ethanol utilization are energy and renewable energy feasible, and cassava ethanol has better feasibility than corn ethanol. Yield and chemicals use are key factors to improve NEV and NREV. Better byproducts utilization and substitution of organic fertilizer for chemical fertilizer help to improve energy efficiency and renewability
Keywords: fuel ethanol; net energy; renewable energy


⊙第104篇⊙

Energy efficiency and potentials of cassava fuel ethanol in Guangxi region of China
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注意:本論文已在Energy Conversion and Management 47 (2006) 1686–1699發表
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SCI、EI 已經收錄本文)
Du Dai a, Zhiyuan Hu b, Gengqiang Pu a, He Li c, Chengtao Wang a
a School of Mechanical and Power Engineering, Shanghai Jiao Tong University, Shanghai 200030, PR China
b Automobile School, Tongji University, Shanghai 200092, PR China
c Hi-tech Development Division, Guangxi Development Planning Committee, Nanning 530012, PR China

Abstract: The Guangxi Zhuang autonomous region has plentiful cassava resources, which is an ideal feedstock for fuel ethanol production. The Guangxi government intends to promote cassava fuel ethanol as a substitute for gasoline. The purpose of this study was to quantify the energy efficiency and potentials of a cassava fuel ethanol project in the Guangxi region based on a 100 thousand ton fuel ethanol demonstration plant at Qinzhou of Guangxi. The net energy value (NEV) and net renewable energy value (NREV) are presented to assess the energy and renewable energy efficiency of the cassava fuel ethanol system during its life cycle. The cassava fuel ethanol system was divided into five subsystems including the cassava plantation/treatment, ethanol conversion, denaturing, refueling and transportation. All the energy and energy related materials inputs to each subsystem were estimated at the primary energy level. The total energy inputs were allocated between the fuel ethanol and its coproducts with market value and replacement value methods. Available lands for a cassava plantation were investigated and estimated. The results showed that the cassava fuel ethanol system was energy and renewable energy efficient as indicated by positive NEV and NREV values that were 7.475 MJ/L and 7.881 MJ/L, respectively. Cassava fuel ethanol production helps to convert the non-liquid fuel into fuel ethanol that can be used for transportation. Through fuel ethanol production, one Joule of petroleum fuel, plus other forms of energy inputs such as coal, can produce 9.8 J of fuel ethanol. Cassava fuel ethanol can substitute for gasoline and reduce oil imports. With the cassava output in 2003, it can substitute for 166.107 million liters of gasoline. With the cassava output potential, it can substitute for 618.162 million liters of gasoline. Cassava fuel ethanol is more energy efficient than gasoline, diesel fuel and corn fuel ethanol but less efficient than biodiesel.
Keywords: Cassava; Net energy; Renewable energy; Fuel ethanol


⊙第105篇⊙

基于混合模型的E10燃料生命周期評估
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注意:本論文已在《上海交通大學學報》2006,40(2):355-358發表
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EI已經收錄本文)
戴 杜,于隨然,浦耿強,王成燾
(上海交通大學 機械與動力工程學院 上海 200030)

摘 要:常規過程式生命周期評估方法在計算中會截斷誤差,導致評估結果被低估。投入產出方法可以避免截斷誤差的產生但不包括產品生命周期的使用階段。為了對E10燃料的生命周期進行評估,本文建立了一個混合生命周期評估模型。生物質生產、乙醇生產/混配以及廢物處理/回收3個子過程采用了投入產出生命周期評估方法,燃料燃燒子過程采用了過程式生命周期評估方法。并對兩種方法的排放值進行求和,計算出E10燃料生命周期VOC、CO、NOX、PM10、SOX、CH4、N2O、CO2排放值分別為21.245、321.488、26.829、3.110、5.904、9.126、3.028、31345.721 g/kg。該結果與過程式生命周期評估結果一致。
關鍵詞:生命周期;E10燃料;投入產出;生物質
中圖分類號:TK6 文獻標識碼:A

E10 Fuel Life Cycle Assessment Based on Hybrid Model
DAI Du, YU Sui-ran, PU Geng-qiang, WANG Cheng-tao
(School of Mechanical Eng., Shanghai Jiaotong Univ., Shanghai 200030, P.R.China)

Abstract: Truncation error occurs in process life cycle assessment (PLCA), which makes underestimation of assessment results. Economic input-output assessment (EIOLCA) can avoid truncation error but excludes use stage of life cycle. To assessing life cycle of E10 fuel. A hybrid assessment model for life cycle of E10 fuel is established. EIOLCA method is used for sub processes of biomass production, ethanol production/mixing and dispose/recycle, and PLCA method is used for sub process of combustion. Through aggregating, the life cycle emission results shows that emission of VOC, CO, NOX, PM10, SOX, CH4, N2O, CO2 are 21.245, 321.488, 26.829, 3.110, 5.904, 9.126, 3.028, 31345.721 gram per kilogram ethanol output, respectively. These results are consistent to results with PLCA method.
Keywords: life cycle; E10 fuel; input-output; biomass


⊙第106篇⊙

Fabrication of enclosed nanochannels in poly(methylmethacrylate) using proton beam writing and thermal bonding
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注意:本論文已在APPLIED PHYSICS LETTERS 88, 093515,2006發表
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P. E. Shao(邵培革), A. van Kan, L. P. Wang, K. Ansari, A. A. Bettiol, and F. Watt
Center for Ion Beam Applications (CIBA), Physics Department, National University of Singapore,
2 Science Drive 3, Singapore 117542, Singapore

Abstract: We report a technique for fabricating enclosed nanochannels in polymethylmethacrylatePMMA using proton beam writing coupled with thermal bonding. Using proton beam writing, straight-walled high-aspect-ratio channels can be directly fabricated through a relatively thick PMMA resist layer spin coated on a Kapton film. By thermally bonding the fabricated structures onto bulk PMMA, peeling off the Kapton substrate, and bonding the remaining exposed side to PMMA, enclosed high-aspect-ratio nano/microchannels can be fabricated. Such enclosed channels can be incorporated into fluidic polymeric devices, and the process is compatible with the fabrication of multilevel three-dimensional fluidic chips with vertical interconnects.


⊙第107篇⊙

自錨式懸索橋空間耦合自由振動分析的理論研究
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注意:本論文已在《北華大學學報》(自然科學版)2003,4(1):84-88發表
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劉春城1,郭立文2,石磊1
(1.大連理工大學土木建筑學院,遼寧大連 116023;
2.吉林省紅石林業局,吉林樺甸 132024)

摘 要:摘要:基于大位移非線性彈性理論的廣義變分原理,考慮了加勁梁軸向壓縮應變能和剪切應變能的影響,建立了三跨自錨式懸索橋空間耦合自由振動的大位移不完全廣義勢能泛函,通過約束變分導出了自錨式懸索橋的豎向撓曲振動、橫向撓曲振動、縱向振動及扭轉振動的基礎微分方程,為自錨式懸索橋的固有振動性狀分析提供可靠的理論依據.
關鍵詞:自錨式懸索橋;耦合;自由振動;泛函;廣義變分中
圖分類號:U448.25    文獻標識碼: A

The oretical Study on Space Coupling Free Vibration Analysis of Self-anchored Suspension Bridge
Liu Chuncheng1, Guo Liwen2, Shi Lei1
(1.Institute of Civil Engineering and Architecture of Dalian University of Technology, Dalian, 116023, China
2.Hongshi Forestry Bureau in Jinlin Province, 132024, China)

Abstract: Based on the generalized potential energy variational principal of nonlinear elasticity theory with large deflection, the incomplete generalized potential energy functional with large deflection is established on the space coupling free vibration of three-span self-anchored suspension bridge by considering the effect of axial compressive and shearing strain energy of stiffening girder. By constraint variation, the differential equations of vertical vibration, later vibration, longitudinal vibration and torsional vibration have been derived. It can provide the theoretical basis for the analysis of free vibration of self-anchored suspension bridge.
Keywords: Self-anchored; Coupling; Free vibration; Function; Generalized variation


⊙第108篇⊙

壓彎耦合效應下自錨式懸索橋自由振動研究
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注意:本論文已在《哈爾濱工業大學學報》2004,36(1):109-111發表
使用者請注明論文出處
EI已經收錄本文)
劉春城[1][2] 張哲[1] 石磊[1]
( [1]大連理工大學橋梁研究所,遼寧,大連 116023
[2]北華大學交通建筑學院,吉林,吉林 132013)

摘 要:基于大位移非線性彈性理論的廣義變分厚理,考慮了加勁梁的壓彎耦合和剪切應變能的影響,建立了三跨自錨式懸索橋空間耦合自由振動的大位移不完全廣義勢能泛函,通過約束變分導出了自錨式懸索橋的豎向撓曲振動、橫向撓曲振動和縱向振動的基礎微分方程,忽略非線性項的影響,進而得到線性振動微分方程.以一座擬建的自錨式混凝土懸索橋為例,求出了豎向振動方程自振頻率的解析解,并與數值解作了比較,證明了這一理論和方法為自錨式懸索橋的固有振動特性分析能提供可靠的依據。
關鍵詞:自錨式懸索橋;壓彎耦合;自由振動
中圖分類號:U442.55 文獻標識碼:A

Free vibration analysis of self-anchored suspension bridges subjected to axial and flexural action efect
LIU Chun.cheng1,2,ZHANG Zhe1 ,SHI Lei1
(1.Bridg,-Institute,Dalian University ofTechnology,Dalian 116023,China;
2.School of Transportation and Architecture,Beihua University,Jilin 132013,China)

Abstract: Based on the generalized potential energy variational principle of nonlinear elasticity theory with large deflection,the incomplete generalized potential energy functional is established on the space coupling free vibration of three-span self-anchored suspension bridge by considering the effect of coupling of flexural and axial action,and shearing strain energy of stifening girder.By constraint variation,the diferential equa tions of vertical vibration,lateral vibration and longitudinal vibration have been derived.With the nonlinear items disregarded,the linear differential equations are established.A self-anchored suspension bridge being constructed is taken as an example for the solution of frequency of linear vertical vibration,and the results are verified by comparing then with those obtained using the numerical methods,and theoretical basis is therefore provided for the analysis of free vibration of self—anchored suspension bridges.
Keywords: self-anchored suspension bridge; coupling of flexural and axial action; free vibration


⊙第109篇⊙

兩級模糊優選模型及非結構性模糊決策理論在橋梁方案比選中的應用
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注意:本論文已在《公路交通科技》2004,21(7):79-82發表
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王會利,李海濱,黃才良,石 磊
(大連理工大學橋梁研究所,遼寧 大連 116023)

摘 要:選擇橋梁設計方案,涉及諸多因素,這些因素在某些情況下相容,在某些情況下又相斥。為了協調這些復雜關系,并降低人為因素的影響,本文引入兩級模糊優選模型及非結構性模糊決策理論。并運用此模型,進行一橋梁的設計選型優化,得到了比較理想的結果,證明了此模型在橋梁方案比選中的實用性。
關鍵詞:模糊優選;非結構性模糊決策;橋梁方案比選
中圖分類號:U442 5      文獻標識碼:A

Two-extreme fuzzy optimum model and non-structural fuzzy decision theory applying to bridge type selection

Wang Hui-li, Li Hai-bin, Huang Cai-liang, Shi Lei
(The Bridge Science Resaerch Institute, Dalian University of Technology, Liaoning Dalian 116023,China)

Abstract: Several factors influence type selection of bridge. Some are consistent, others are inconsistent. In order to harmonize the relations among the factors and decrease the subjective influence, the two-extreme fuzzy optimum model and non-structural fuzzy decision theory are introduced. The method of fuzzy optimum decision has been successfully used in an example of type selection of a bridge, which includes four design projects.
Key words: Fuzzy optimum decision; Non-structural fuzzy decision; Type selection of bridge


⊙第110篇⊙

多支承激勵下自錨式懸索橋空間地震反應分析
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注意:本論文已在《哈爾濱工業大學學報 》2004,36(11):1568-1570發表
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EI已經收錄本文)
劉春城1,2 張哲1 石磊1
(1.大連理工大學橋梁研究所,遼寧 大連 116023
2.北華大學 交通建筑學院 吉林 吉林 132013)

摘 要:基于隨機振動理論,考慮了地震動空間效應,對一座主跨240米自錨式混凝土懸索橋在多支承激勵下進行了地震反應分析,以及在地震波的三向正交分量獨立作用和聯合作用下的地震反應進行了數值計算,探討了行波效應和部分相干效應對自錨式懸索橋地震反應的影響.
關鍵詞:多支承激勵 自錨式懸索橋 地震反應

Spatial seismic response analysis of self-anchored suspension bridges subjected to multiple-support excitations

Liu Chun-cheng1,2, Zhang Zhe1, Shi Lei1
(1.Bridge Science Resaerch Institute, Dalian University of Technology, Liaoning Dalian 116023,China
2.School of Transportation and Architecture, Beihua University, Jilin 132013, China)

Abstract: Based on random vibration theory, by taking into account the seismic action with spatial variation, the earthquake respons of a self-anchored suspension bridge with center span of 240m to multiple-support excitation is investigated, and numerical calculation is presented for seismic response of self-anchored suspension bridge by considering traveling effect and correctated effect is discussed in detail.
Key words: multiple-support excitations; self-anchored suspension bridge; earthquake reponse


⊙第111篇⊙

Darboux Transformation and Soliton-like Solutions for a Generalized q-KdV Hierarchy
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注意:本論文已在Journal of the Physical Society of Japan,Vol. 73, No. 11, November, 2004, pp. 2991–2995發表
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Engui FAN(范恩貴)
Institute of Mathematics and Key Lab for Nonlinear Mathematical Models and Methods,
Fudan University, Shanghai 200433, P. R. China
(Received July 5, 2004)

Abstract:By introducing a q-deformed spectral problem, we derive a new generalized q-KdV hierarchy with variable coefficients. Darboux matrix technique is further extended to construct an explicit and universal Darboux transformation for the q-KdV hierarchy. It is found that the Darboux transformation admits a theorem of permutability theorem and a superposition formula. In particular, the soliton-like solutions whose speeds may depend on time variable t are obtained by applying the Darboux transformation and superposition formula.
KEYWORDS: generalized q-KdV hierarchy, Darboux transformation, theorem of permutability, soliton-like solution


⊙第112篇⊙

An algebro-geometric solution for a Hamiltonian system with application to dispersive long wave equation
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注意:本論文已在JOURNAL OF MATHEMATICAL PHYSICS ,46, 032701, 2005:1-21發表
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Y. C. Hon(a)
Department of Mathematics, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
E. G. Fan(b) (范恩貴)
Institute of Mathematics, Fudan University, Shanghai 200433, People’s Republic of China
(Received 14 October 2003; accepted 3 December 2004; published online 8 February 2005)

Abstract:By using an iterative algebraic method, we derive from a spectral problem a hierarchy of nonlinear evolution equations associated with dispersive long wave equation. It is shown that the hierarchy is integrable in Liouville sense and possesses bi-Hamiltonian structure. Two commutators, with zero curvature and Lax representations,for the hierarchy are constructed, respectively, by using two different systematic methods. Under a Bargmann constraint the spectral is nonlinearized to a completely integrable finite dimensional Hamiltonian system. By introducing the Abel–Jacobi coordinates, an algebro-geometric solution for the dispersive long wave equation is derived by resorting to the Riemann theta function.


⊙第113篇⊙

基于裝配函數的車床虛擬裝配
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注意:本論文已在《機電一體化》2004,10(5):42-45發表
使用者請注明論文出處

周立波, 田中旭, 邸義
上海大學CIMS和機器人中心 上海 200072

摘要:虛擬裝配是虛擬制造的關鍵技術之一,裝配過程仿真是實現產品虛擬裝配的一個重要環節。在分析了虛擬機床裝配仿真過程的基礎上,提出了一種機床虛擬裝配的描述語言及其相對應的虛擬裝配函數的實現方案。這種語言能夠使機床技術人員用直觀、便捷的方法來實現虛擬機床的裝配,并通過實例驗證了該技術的有效性。
關鍵詞:裝配函數 虛擬裝配 裝配仿真 描述語言

Virtual Assembly of Lathe Based on Assembly Function
Zhou Libo,Tian Zhongxu, Di Yi
(CIMS & Robot Center, Shanghai University, Shanghai, China, 200072)

Abstract:Virtual assembly is one of the key technologies of virtual manufacture, and animation and simulation module of assembly process is an important link to realize product virtual assemble. Based on analyzing the process of simulation of machine assembly,the realization of a language and virtual assembly function, which describes simulation of machine assembly is introduced,。Machine technician can use this language to show the assembly expediently,and an example is given to show the validity of the technology.
Keywords: assembly function; virtual assembly; assembly simulation; description language


⊙第114篇⊙

A New Routing Algorithm of Two-tier LEO/MEO Mobile Satellite Communication Systems
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注意:本論文已在2005 Asia-Pacific Conference on Communications, Perth, Western Australia, 3 - 5 October 2005.發表
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Wu Di, Li Qing
(Dept. of Computer Science Dalian University of Technology Liaoning, China, 116024)

Abstract:The performance of a two-tier LEO/MEO satellite network including inter-satellite links (ISL’s) is analyzed. Specific emphasis is laid on the design of an ATM-based routing scheme for the ISL part of the system (MEO layer). The approach is to prepare a virtual topology by means of virtual path connections (VPC’s) connecting all pairs of end nodes in the ISL sub-network for a complete period in advance, similar to implementing a set of (time dependent) routing tables. The search for available end-to-end routes within the ISL network is based on a new routing Algorithm (S-DRA) integrates the advantages of Static Routing and Dynamic Routing. Additionally, a new quick clustering scheme is introduced to monitor the faults to guarantee the usability of VPC. The new algorithm guarantees that: 1) the survey of VPC route is not carried on blindly no longer because of the application of the clustering scheme, 2) the flow of control information is reduced, 3) whereas the channel of link is allowable, it can reduce handover frequency as much as possible. Finally, a simulation on MEO layer analyzes the performance of the new routing algorithm.
Index Terms--satellite network, ISLs, routing algorithm


⊙第115篇⊙

復雜產品開發活動序列分析方法研究
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注意:本論文已在《中國機械工程》2005,.16(17):1536-1540發表
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曹守啟1  陳 云2  韓彥嶺3  方明倫1
1.上海大學,上海,200072
2.上海財經大學,上海,200433
3.北京科技大學,北京,100083

摘 要:應用圖論中可達矩陣的性質與原理對產品開發活動的組織方式及其序列作了定量分析,實現對產品開發活動的按區域劃分,從而明確了影響產品開發過程中的主要路線和關鍵環節;通過對產品開發可能路徑持續時間和作用概率的分析研究,為并行產品開發過程的組織和實施提供決策依據.
關鍵詞:復雜產品;任務分解;活動序列;開發過程;關鍵路徑
分類號:TH16;TP399
文章編號:1004-132X(2005)17-1536-05


Research on Analysis Method of Development Activity Sequences for Intricate Products

Cao Shouqi1  Chen Yun2  Han Yanling3  Fang Minglun1 
1、Shanghai University,Shanghai,200072
2、Shanghai University of Finance&Economics,Shanghai.200433
3.University of Science and Technology Beijing,Beijing,100083

Abstract:Research on Analysis Method of Development Activity Sequences for Intricate ProductsAbstract:This paper made quantitative analyses to activity sequences and organization schema of production development with the principle of reachability matrix in graphics theory, realized division according to activity zone of product development, and effects on primary route and critical juncture of development definitely. By researches on time duration and action probability of product development, we provided the decision-making reliance for organization and execution of development routes.
Key words:intricate product; task decomposition; activity sequence; development process; critical path


⊙第116篇⊙

基于約束的復雜產品開發過程與活動路線分析
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注意:本論文已在《機械科學與技術》 2005,.24(12):1391-1395發表
使用者請注明論文出處

曹守啟1  陳云2  韓彥嶺1  方明倫1
  1.上海大學,上海,200072
2.上海財經大學,上海,200433

摘 要:為實現在不同階段、按不同層次和區域分析和控制產品開發微觀過程的目的,提出一種基于"自組織-被組織"方法論規劃和設計產品開發過程的方法.在面向過程的任務分層分解和基于約束的產品開發活動組織過程表達中,把與過程相關的約束和影響因素,通過節點間邏輯狀態及其取值概率來反映和體現;應用圖論中可達矩陣性質與原理定量分析產品開發活動序列及其組織路線,實現產品開發宏觀過程管理和微觀過程控制的有機結合,使產品開發活動的組織方式、狀態演化和工作流程始終處于透明和可控的環境下觀察和分析,幫助項目管理人員明確影響產品開發過程的主要路線和關鍵環節,克服傳統方法綜合多個要素、跨越整個過程建模和分析的困難.
關鍵詞:自組織;任務分解;活動序列;約束;關鍵路徑
分類號:TH16;TP399  文獻標識碼:A
文章編號:1003-8728(2005)12-1391-05

Analysis of Complicated Product Development Process and its Activity Line Based on Restraint

Cao Shouqi1   Chen Yun2  Han Yanling1   Fang Minglun1 
1、Shanghai University,Shanghai,200072
2、Shanghai University of Finance&Economics,Shanghai.200433


Abstract:Analysis of Complicated Product Development Process and its Activity Line Based on RestraintCao Shouqi,Chen Yun, Han Yanling, Fang Minglun (1. CIMS and Robot Center, Shanghai University, Shanghai 200072; 2. Shanghai University of Finance and Economics, Shanghai 200433)Abstract:In order to realize the purposes of analyzing and controlling micro-processes of product development according to different levels and regions in different phases, a planning and design method of the product development processes is put forward on the basis of self-organizing and organized methodology. In the process of stratifcation and decomposition of task and product development based on restraint, the influence and restraint factors in connection with the processes are reflected and embodied by logic state and evaluation probability. By applying quality and principle of reachability matrix in graphics theory, activity sequence and its route of product development are analyzed quantitatively; macroscopic process management and microcosmic process control of product development are realized, and the organization mode, state evolution and work flow of product development activities are observed and analyzed under a transparent and controllable environment all the time. All these help project managers to know about the primary route and key point juncture of product development processes and overcome the difficulty of traditional methods in the way .of modeling and analysis by synthesizing multiple elements and crossing entire processes.
Key words:self-organizing; task decomposition ; activity sequence; restraint ; critical path


⊙第117篇⊙

非均質材料零件的材料設計
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張秀娟[1] 陳克彰[2] 馮辛安[3]
[1]大連鐵道學院機械工程系,遼寧大連116028
[2]香港大學機械工程系 ,香港
[3]大連理工大學機械學院,遼寧大連116024

摘 要:闡述了非均質材料零件設計優化的數學模型,并采用靈敏度分析以及最速下降法對其各個材料區域的材料性能進行設計優化,得到最佳材料性能參數后,再從非均質材料數據庫中找到相應的工程材料,合成滿足設計要求的非均質材料零件.該方法為設計者提供了切實可行的非均質材料零件的材料設計方法.
關鍵詞:非均質材料零件 材料設計 數學優化模型 靈敏度分析 最速下降法
分類號: TH140.8

Material Design of Heterogeneous Components

ZHANG Xiu—juan ,CHEN Ke—zhang ,FENG Xin—an
(1.Dept.of Mechanical Engineering.Dalian Railway Institute.Dalian 116028 China;2.Dept,of Mechanical Engineering.The University of Hong Kong.Hong Kong;3.Dept、of Mechanical Engineering.Dalian University of Technology.Dalian 1 16024 China)


Abstract:TMs paper presents the mathematical mod el for the optimization of heterogeneous components I an d the method using sensitivity analysis and steepest descent method to optimize material properties,the component is then identified.After searching for the materials from heterogeneous material database according to the corresponding optimum material data and combining the heterogene- OUS compo nents,the material is synthetized.To designer,this method is feasible and effective for the material design of heterogene-
OUS compo nents.
Key words:heterogeneous components;mathema~cal model:sensitivity analysis and optimization;steepest descent method


⊙第118篇⊙

數字制造的概念與關鍵技術
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注意:本論文已在《現代制造工程》 2005,9:106-109發表
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張秀娟
大連交通大學機械工程學院,遼寧大連,116028

摘 要:闡述數字制造的基本概念與內涵,全面介紹數字制造的關鍵技術和應用,并提出數字制造的發展趨勢。
關鍵詞:數字制造 概念與內涵 關鍵技術 發展趨勢

Concepts and key technique of digital manufacturing

ZHANG Xiu—juan ,CHEN Ke—zhang ,FENG Xin—an
(1.Dept.of Mechanical Engineering.Dalian Railway Institute.Dalian 116028 China;2.Dept,of Mechanical Engineering.The University of Hong Kong.Hong Kong;3.Dept、of Mechanical Engineering.Dalian University of Technology.Dalian 1 16024 China)


Abstract:The concept and connotation of digital manufacturing are introduced. Key techniques and applications of digital manufacturing are described. The development trend of digital manufacturing is put forward lastly.
Key words:Digital manufacturing Concept and connotation Key techniques Development trend



⊙第119篇⊙

流形網格上機構運動軌跡的參數化生成方法
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注意:本論文已在 《機械工程學報》(中文版))2006,42(8):84-88,94發表
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孫玉文1 王海霞1 劉偉軍2 王越超2
(1. 大連理工大學精密與特種加工教育部重點實驗室 大連 116024;
2. 中國科學院沈陽自動化研究所 沈陽 110016)

摘 要:在三角網格模型上操作機構的運動軌跡生成通常采用截面線法,當網格邊界形狀復雜時由此生成的運動軌跡很難保證與邊界的一致性,從而產生較多較短的路徑。基于調和映射技術,提出了復雜網格曲面上機構運動軌跡參數化生成的一般方法。通過將復雜網格模型同胚映射到平面上的圓形區域或矩形區域,建立了在參數曲面基礎上的ZigZag型及輪廓型等參數線軌跡的具體規劃模型,給出了該種情況下軌跡離散點、行距及機構運動干涉的計算方法與解決方案。實例表明該軌跡生成方法具有良好的邊界一致性,并因其固有的軌跡磨光性質提高了運動機構的動力學性能及運行效率。
關鍵詞:三角網格 調和映射 軌跡規劃 可接近性分析

PARAMETRIC METHOD FOR KINEMATIC PATH GENERATION FROM MANIFOLD MESHES

un Yuwen1 Wang Haixia1 Liu Weijun2
Wang Yuechao2
(1. Key Laboratory for Precision & Non-traditional Machining of Ministry of Education, Dalian University of Technology, Dalian 116024;
2. Shenyang Institute of Automation, Chinese Academy of Science, Shenyang 110016 )


Abstract:Triangular mesh surface has gained wide applications in industrial field. However, the tool path generation methods for polyhedral machining are very limited and the iso-plane method is still the common used method. A conformal map based iso-parametric method for kinematic path generation is proposed. Through establishing the parametric relations between the triangular meshes embedded in the 3D space and the rectangular or circular region on the 2D plane, the Zigzag or contour paths are finally implemented by inversely mapping the planar iso-parametric paths into the physical space. Also, the issues of CC point and side interval calculation as well as interference detection are discussed in detail. The results show that the proposed method is boundary-conformed and can improve machining dynamics and efficiency greatly.
Key words:Triangular mesh, Conformal map, Tool path, Accessibility analysis


⊙第120篇⊙

SKIN-CORE STRUCTURE IN MESOPHASE PITCH-BASED CARBON FIBERS: CAUSES AND PREVENTION
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注意:本論文已在Carbon, Vol. 36, No. 12, pp. 1719–1724, 1998發表
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YONG-GEN LU¨(呂永根) ,a,* DONG WU,b QING-FANG ZHA,a LANG LIU¨ a and
CHANG-LING YANGa
a.Institute of Coal Chemistry, Chinese Academy of Sciences, Shanxi, 030001 Taiyuan,
People’s Republic of China
b.Department of Chemical Engineering, Taiyuan University of Science and Technology, Shanxi,
030001 Taiyuan, People’s Republic of China


Abstract:To prohibit skin-core structure from appearing in mesophase pitch based carbon fiber (CF) with a large diameter (30–50 mm), measures such as decreasing oxidation temperature, prolonging holding time and increasing the oxygen partial pressure in the oxidative atmosphere were taken. EPMA (electron probe X-ray micro-analyzer) was utilized to detect the oxygen content distribution along the diameter of oxidized pitch fiber (OF). The transverse structure of OFs and CFs was observed under a scanning electron microscope (SEM). It was found with certainty that the skin-core structure in CFs is caused by steep oxygen content gradient along the diameter of their OFs. The oxygen distribution in
OFs was controlled by the oxidative stabilization conditions. In this work, the CF whose precursor fiber had been oxidized at 240°C in a flow of pure oxygen for 10 hours exhibits no skin-core structure and possesses a high tensile strength. The kinetics of stabilization was also studied. It can be concluded that those factors which increase oxygen diffusion or depress oxidative reaction are effective in overcoming skin-core structure in CFs. ? 1998 Elsevier Science Ltd. All rights reserved.
Key words:A. Carbon fibers, mesphase, B. EPMA, D. Diffusion.


 

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