Multi-Piece Mold Design Based on Linear Mixed-Integer Program Toward Guaranteed Optimality
|
|
- Shanon Bond
- 6 years ago
- Views:
Transcription
1 INTERNATIONAL CONFERENCE ON MANUFACTURING AUTOMATION (ICMA200) Multi-Piee Mold Design Based on Linear Mixed-Integer Program Toward Guaranteed Optimality Stephen Stoyan, Yong Chen* Epstein Department of Industrial and Systems Engineering, University of Southern California, Los Angeles, CA 90089, USA *Corresponding author: (23) Abstrat Multi-piee molds are a type of molding tehnology, whih onsist of more than two mold piees and are assembled/dissembled lie a spae puzzle. Based on suh molds, omplex parts an be made for limited run prodution. Compared to traditional two-piee molds, parts with muh more omplex geometries an be made; however, this also brings hallenge in designing suh multi-piee molds. Previous wors to address the problem are all based on heuristis. In this paper, we present a multi-piee mold design framewor based on linear mixedinteger program. In our method, multi-piee mold design with guaranteed optimality on the number of mold piees an be generated for any given CAD model of a molded part. The formulation of multi-piee mold design as a linear mixed-integer program is presented. The related multi-piee mold design framewor is disussed. Some examples are provided whih illustrate the effetiveness and effiieny of our approah. Keywords Computer-aided design; deision support; rapid tooling; linear mixed-integer programming Bottom View Injetion Molded Part Top View. INTRODUCTION Multi-piee molds suh as spae puzzle modeling developed by Protoform GmbH ( an have more than two mold piees. In the injetion molding proess, mold piees are first hand-loaded into a mold base mounted on the injetion molding mahine. During part injetion and ooling proess, the mold piees are aurately and seurely lamped into the holding devie. Finally eah mold piee is hand-removed from the mold base to release the injetion molded part. An example of multi-piee molds and related injetion molded part provided by Protoform GmbH is shown in Figure. As shown in the figure, eah mold piee an have its own parting diretion (PD), along whih, the mold piee an be separated from the part. () Compared to the traditional two-piee molds, multi-piee molding an produe limited run prodution parts with more omplex geometries. (2) Compared to rapid prototyping (RP) proesses suh as Stereolithography Apparatus (SLA), multi-piee molding an effiiently produe a small quantity of parts (e.g. 00); more importantly, the fabriated parts an be made in desired injetion molding materials that may not be available to RP proesses. Hene multi-piee molding has beome an important tooling tehnology in the era of mass ustomization, in whih limited run prodution is inreasingly beoming a ommon industrial pratie. Molded Piees Fig. : An example of multi-piee molds given by Protoform GmbH. Given the geometry of a part, depending on the seletion of mold design variables, a different number of mold piees may be required to form the part. It is desired to minimize the number of required mold piees beause fewer mold piees redues the tooling ost and simplifies the operation of the mold. Therefore, in this paper, we will onsider the automation of multi-piee mold design problem defined as: Problem MPMD: Multi-Piee Mold Design. Given a solid part and a mold base, design the minimum number of mold piees that an form the avity of the part in the material injetion proess, and an be disassembled properly in the part ejetion proess.. Related Wor The automation of mold design for injetion molding has been extensively studied before. Some representative wor an be found in [~6]. Most of the wor fouses on two-piee molds, inluding the determination of parting diretion, parting line, parting surfae, and underut deteting. Among them, the seletion of parting diretion has reeived muh
2 attention sine it is an important step in the automati mold design proess. Reently, new programmable graphis hardware aelerated algorithms have also been presented to test the moldability of parts and help in redesigning them [7]. Chen and Rosen [8, 9] first presented a multi-piee mold design method that allows three-dimensional mold deomposition. More reently, Gupta s group presented a set of geometri algorithms for automated design of multi-piee permanent molds [0], sarifiial multi-piee molds [], and multi-stage molding [2]. These wors provide an exellent groundwor on multi-piee mold design to improve upon. One ey problem of the urrent approahes is that the multi-piee molds are designed based on heuristis. Hene no optimality an be guaranteed for a given arbitrary geometry. For example, in designing multi-piee permanent molds [0], a set of andidate parting diretions are seleted from () prinipal diretion, (2) planar fae normal, and (3) ylindrial/onial fae axis. Based on them, a greedy sheme is then used in identifying the minimum number of mold piees. In this paper, a multi-piee mold design method based on linear mixed-integer program is presented. In our method, a lower and upper bound on the number of mold piees are first identified for a given part geometry. Based on them, heuristis an then be used in further improving the generated design. Our design framewor, for the first time, provides a solid foundation in pursuing multi-piee mold design with guaranteed optimality..2 Problem Formulation Before disussing our approah, we first present a more aurate formulation of the aforementioned Problem MPMD as follows. Problem MPMD: Multi-Piee Mold Design. Given a polygonal model (P) and a mold base (Ψ), design a n-piee mold M = { m, m2,, m n } to: Minimize: number of mold piees (n). Subjet to: () Eah mi M is a onneted solid; (2) Eah mi M has a parting diretion d i suh that m i an be dissembled along d i ; (3) M n = m satisfies M = Ψ P. i The multi-piee mold design problem onsidered in this paper is essentially the same as the ones defined in [8] and [0]. 2. MULTI-PIECE MOLD DESIGN APPROACH For a part to be moldable, every faet on the part needs to be aessible from at least one diretion. Usually suh a diretion an be easily found for eah individual faet; however, the ore hallenge in mold design is to find the minimum number of diretions that are ommon to all the faets of the part. 2. Mold Design Based on Visibility of Faes Chen et al. [3] formulated demoldability as a visibility problem and presented a set of important omputational tehniques suh as visibility and Gaussian maps (V-Maps and G-Maps). For a planar surfae F, its V-map is a hemisphere entered on the unit outward normal. By alulating the intersetions of all V-maps of region faes, allowable draw ranges an be omputed. Several approahes and algorithms based on spherial polygons have been presented for different appliations [4-5]. However, the algorithms and related data strutures are rather ompliated. In addition, it taes onsiderable omputational time to ompute the exat V-map intersetions based on spherial surfaes. Instead, Chen and Rosen [8] presented an alternative approah based on linear program for evaluating the parting diretions of a set of surfaes. Suppose a onneted region R onsists of fae F i (with unit fae normal N i and area A i, i n). If a ommon diretion d(d x, d y, d z ) exists suh that every faet F i an be aessible from suh a diretion, d is a andidate parting diretion of the region. In addition, the ease of ejetion an be used as the riterion to hoose an optimal parting diretion from a feasible range. For a fae F i, its ease of ejetion an be determined by the draft angle and the area in shear ontat with the related part fae during the moldopening operation (i.e. Ai( Ni d) ). Hene an optimization problem for determining a parting diretion of region R an be formulated as follows. Maximize: n A( N d) i Subjet to: N d N d N d 0 i + + for fae F i xi x yi y zi z d + d + d = (sphere onstraint) x y z A unit sphere related to the sphere onstraint an be approximated by a set of linear surfaes with aeptable errors. Suppose the equations of a planar surfae M are Mxldx + M yldy + Mzldz = μl with fae normal (M xl, M yl, M zl ) toward the inside. A linear problem an be formulated for evaluating a parting diretion of the region. Problem PDLP: Parting Diretion Linear Problem. n Maximize: Ai( Ni d) (2.) Subjet to: N d + N d + N d 0 for fae F i (2.2) xi x yi y zi z Mxldx + M yldy + Mzldz μl for fae M l. (2.3) A linear program problem in 3 dimensions an be solved in O(n) time (n is the number of onstraints) and on linear storage. Therefore, the running time to solve Problem PDLP is very fast, typially in milliseonds for thousands of faes based on a ommerial solver (e.g. LINGO system - More importantly, the omputation proess of finding a parting diretion for a set of faes beomes muh easier and more robust. 2
3 Motivated by suh a linear program approah, we further develop a linear mixed-integer program for determining a minimum number of parting diretions for all the fae of a given part. The optimization formulation is disussed in Setion 3. A simple example (Test in Setion 6) is shown in Figure 2 to illustrate the objetive in Problem PDLP, whih is also used in the linear mixed-integer program. For a simple ube, there is an infinitely number of parting diretions that an be used in its mold design. However, onsidering the ease of ejetion, the two diretions, d and d 2 as shown in the figure, are the most desired. In suh diretions, the projetion area n Ai( Ni d + Ni d2 ) is also the maximum. Fig. 2: A simple example to illustrate the optimization objetive in PDLP. 2.2 Basi Elements for Multi-Piee Mold Design In Problem PDLP, a single fae F i is used as the basi element in evaluating a feasible parting diretion. However, suh a fae is not a good element in identifying a minimum number of parting diretions in multi-piee mold design. This is due to the aessible diretion to a fae may be bloed by its neighboring faes (e.g. two neighboring faes between a onave edge); however, suh bloage is hard to be inorporated if faes are direted used as the basi element. As shown in Figure 2, any pair of diretions an be used in mold design if the given part ontains only onvex edges. Based on suh an idea, Chen et al. [3] omputed a set of poets based on the onvex hull of an objet to apture all the non-onvex regions. Aordingly, the visibility map of eah poet an be omputed and the parting diretions to maximize the number of ompletely visible poets an be determined. Top View Bottom View Fig. 3: An example of poets for a test part. An example of poets for a test part (Test 3 in Setion 6) is given in Figure 3. The four poets of the part are shown in different olors. It an be seen that a poet is a molding feature whih ontains multiple onave and onvex edges. As disussed in [8], poets give us less design freedom in trying different ombinations of elements; hene they are also not good elements for identifying a minimum number of parting diretions in multi-piee mold design. As disussed in [8], onave edges (i.e. the dihedral angle of two neighboring faes is bigger than 80 o ) an apture the bloage of aessible diretions between neighboring faes. Based on suh edge lassifiation, two types of elements an be defined as follows. Definition 2.. A fae F is a onvex fae if all edges of F are onvex edges. Definition 2.2. A Conave Region is a set of onneted faes suh that: () all internal edges of the region are onave edges; and (2) all boundary edges of the region are onvex or flat edges. As an example, the onave regions for the test part in Figure 3 are shown in Figure 4. There are a total of 2 onave regions whih are shown in different olors; in addition, there are 68 onvex faes whih are drawn in wireframe in the figure. Hene, ompared to poets, the design freedom based on them for identifying a minimum number of parting diretions has been signifiantly inreased. Top View Bottom View Fig. 4: An example of onave regions and onvex faes for a test part. Similar to [8], onave regions and onvex faes are used as the basi elements in our multi-piee mold design method. A similar strategy has also been adopted in their generation. However, different from [8] that is based on a 3D geometri modeler (ACIS from Spatial our urrent method is based on polygonal meshes (i.e. the input model is defined in a STL file). Hene the approah in omputing onave regions and onvex faes is aordingly modified as follows by adding a onept of Convex_Edge_Vertex. () Classify all edges as onave, onvex and flat. (2) Assign two faes to the same region if they share a onave or flat edge. (3) Identify all the internal onvex edges of eah region and mar the verties of suh edges as Convex_Edge_Vertex. Notie we do not want a region to have internal onvex edges (i.e. all the internal edges should be onave as shown in Definition 2.2). (4) Regenerate regions by assigning two faes to the same onave region if they share a onave edge, or a flat edge if suh a flat edge has no vertex that is mared as Convex_Edge_Vertex. 3
4 2.3 Approah Overview Based on the identified basi elements (a set of onave regions and onvex faes), the essene of multi-piee mold design is to try a different ombination of them, and aordingly identify a design with the best performane (i.e. the minimum number of mold piees and the easiness of ejetion if the same number of mold piees is ahieved). There have been various approahes to solve suh ombination problem between elements (e.g. the well-nown napsa problem). General solution methods involve: (i) searhing all possible ombinations of variables, (ii) using heuristis suh as greedy heuristi, or (iii) optimization methods suh as utting planes or the branh and bound method. Eah solution method has advantages and disadvantages. Searhing all ombinations, for example, has osts with respet to solution time, espeially with large-sale problems where validating a solution may tae years. Heuristis typially generate fast solutions, but they do not guarantee optimality. Optimization methods an guarantee optimality and use tehniques that onverge faster than searhing the whole solution spae; however, they generally perform slower than heuristis. When models involve integer variables (suh as the one in the next setion), the problems with the various solution methods desribed above get even worse. Although optimization methods have their trade-offs, depending on the omplexity of the problem, urrent state-ofthe-art solvers suh as CPLEX from ILOG ( an solve large-sale problems in reasonable time. As disussed in Setion, the previous multi-piee mold design methods are based on heuristis. They are effetive but do not provide optimality and also may fail for geometries that have not been onsidered when generating suh heuristis. In this paper, we formulate the Problem MPMD into a linear mixed-integer program and solve it based on optimization methods. As shown in Setion 6, by using CPLEX, suh a problem an be solved within 0 seonds for optimal solutions of the four test problems. An overview of our method based on an example (Test 2 in Setion 6) is shown in Figure 5. () A given part to be injetion molded is shown in Figure 5.a. The part has 64 triangles. They an be lassified into 3 onave regions (drawn in different olors) and 40 onvex faes (drawn in wireframe) as shown in Figure 5.b. (2) Based on suh elements, a linear mixed-integer program is formulated and programmed in CPLEX. Aordingly two parting diretions, d = (0, 0, ) and d 2 = (0, -, 0), are identified by the optimization solver. (3) The optimization solution provided us a lower bound on the solution (i.e. n=2). Based on them, all the onave regions and onvex faes an be ombined into two mold piee regions (shown in two different olors in Figure 5.). Sine multiple solutions may exist, a best one may be identified based on molding design nowledge. (4) Based on the generated mold piee regions and related parting diretions, parting lines and parting surfaes an be identified. Aordingly two mold piees, M and M 2, an be onstruted (refer to Figure 5.d). Notie there is a one to one orrespondene between the mold piees and the mold piee regions. Also the two mold piees an be assembled and disassembled properly in the related parting diretions. Additional loing features an be added in the mold piees. In this paper, we will mainly fous on the proess of generating mold piee regions from onave regions and onvex faes. Aordingly, the remainder of the paper is organized as follows. In Setion 3, we present the optimization formulation for Problem MPMD. In Setion 4, we disuss the fae onnetivity of mold piee regions based on the identified part diretions. The further improvements of the mold design are disussed in Setion 5. The test results are disussed in Setion 6. Finally, we give onlusions in Setion 7. (a) () (d) M d d 2 (b) Fig. 5: An overview of our method. M 2 3. OPTIMIZATION FORMULATION FOR COMPUTING PARTING DIRECTIONS Before getting into the intriate details of the problem, we first outline the deision variables and parameters assoiated with the model. To begin we define: n: the total number of parting diretions of mold piees; 4
5 p: the total number of onave regions; m: the total number of approximated spherial surfaes; and their respetive sets as: φ :={i: i [,n]}: the set of parting diretions; ψ := {: [,p]}: the set of onave regions; θ := { : [,m]}: the set of spherial surfaes. In addition to the number of onave regions, there also exists a number of surfaes assoiated with eah region, whih do not neessarily have the same length. Thus, we define the set of surfaes assoiated with eah onave region and introdue the set of onvex surfaes as: β : the set of surfaes in eah onave region =,...,p; β : the set of onvex surfaes. The deision variables involved in the optimization problem are as follows: d i =[d i x,d i y,d i z ]: the vetor of parting diretions for mold piees,...,n; g i (): the binary variable used to enfore onstraints related to parting diretions,...,n for =,...,p onave regions; g i( β ): the binary variable used to enfore onstraints related to onvex surfaes for parting diretion,...,n; z i : a ontinuous variable used to satisfy the absolute value funtion in the objetive. Finally, the parameters involved with the deision variables in the design are defined as: N(, β )=[N x (, β ),N y (, β ),N z (, β )]: the matrix with β surfaes related to onave regions =,...,p; N ( β )=[N x( β ),N y( β ),N z( β )]: the matrix of onvex faes with β surfaes; M =[ M x, M y, M z ]: the vetor defining approximated spherial surfaes =,...,m; A(, β ): the area of onave regions with β surfaes for =,...,p; A ( β ): the area of onvex regions with β surfaes; u : a salar value related to the approximated spherial surfaes =,...,m; L: the lower bound of parting diretion for mold piees; U: the upper bound of parting diretion for mold piees. The design desribed in the earlier setions requires the solution to two optimization problems. Given a set of onstraints that define the mold we want to reate, the first problem (I) entails finding the minimum number of vetor parting diretions d i neessary to design the mold. After we now the minimum number of parting diretions, the seond problem (II) involves maximizing the surfae area overed in forming the mold piees. The first optimization problem (I) is the following: After solving the problem above, we let n be the number of d i 0 in the solution to (3.)-(3.). Then, the seond optimization problem (II) is: The onstraints are the same for both problems sine they define the boundaries of the mold to be reated. Constraints (3.2)-(3.3) and (3.4)-(3.5) ensure that at least one parting diretion vetor d i satisfies the desired inequality and the rest an be turned ``off" via the binary variables g i () and g i( β ); respetively. The problem with both (3.)-(3.) and (3.2)- (3.3) is the objetive funtions and onstraints are nonlinear and also involve binary variables g i () and g i( β ). However, the NonLinear Mixed-Integer Program (NLMIP) of (3.)-(3.) and (3.2)-(3.3) an be onverted to an equivalent linear program with the introdution of a deomposition strategy and a few additional variables and onstraints. The linear transformation allows the problem to be muh more tratable and easier to solve. Fig. 6: Problem (I) subproblem deompositions for variables d i. 5
6 We now desribe the linear transformations and deomposition strategy used to mae the problem more tratable. In the objetive of problem (I), the NLMIP minimizes the number of variables d i uses in the solution. Sine we are looing for the lowest number i that satisfies (3.2)-(3.), we deompose problem (I) into subproblems that inrease in size by one variable d i. As shown in Figure 6, problem (3.)-(3.) is solved for the number of variables orresponding to eah subproblem until a solution is generated, in whih ase we stop. Given the nature of the problem, we now that at least two variables will be needed to generate a solution, thus subproblem () begins with d and d 2. Then we stop after the first instane when subproblem (i n) obtains an optimal solution. The objetive of problem (II) aims to maximize the surfae area assoiated with the absolute value of the diretion vetor and the orresponding surfae region. This has a linearly equivalent set of equations by introduing the following: This equates to solving the following linear Mixed-Integer Program (MIP): This is also done for N ( β )d i where z i is used, whih is shown in equations (3.22), (3.25) and (3.26) below. The nonlinear onstraints in the problem an also be addressed in a similar fashion, whih mae the problem more tratable and less omplex. The nonlinear onstraints in (3.2) and (3.4) an be onverted into linear onstraints by using the following equation: where Λ is a large value. Here, when g i () is equal to zero then this onstraint is essentially turned ``off" sine the large Λ value will satisfy the inequality for any d i. When g i () is equal to one then N(, β )d i 0 must be satisfied, whih is the desired funtion of onstraint (3.2). This is again repeated for g i( β )N ( β )d i, as is shown below in equation (3.29). Finally, the upper and lower bound onstraints of (3.7) and + (3.8) an be linearly expressed by defining d i =d i - d - i, d i+ 0, + d i- 0. Hene, d i and d - i are simply the positive and negative omponents of d i ; respetively. Then, satisfying the absolute value of the onstraints is provided by the following equations: where δ i i φ. Thus, the original problem of solving problem (I) and (II) separately an now be done in one equivalent linear problem. where (3.22)-(3.43) is solved using an inreasing number of parting diretions d i until the first instane that generates a solution, as desribed above and shown in Figure CONNECTIVITY OF MULTI-PIECE MOLD DESIGN As disussed in Setion 2.3, the formulated linear Mixed- Integer Program an be programmed in a CPLEX optimization solver. Advaned MIP algorithms based on methods suh as branh and bound an be used in finding an optimized solution. One benefit we gain based on our approah is that we an easily inorporate different draft angle requirements in our problem. That is, for a part to be injetion molded, its surfaes that are parallel to the paring diretion must be drafted at least an angle γ in order to ease the ejetion of the part and redue the damaging possibility of the part and molds. The minimal draft angle mainly depends on the molding proess and material. For some molding proesses suh as urethane rubber molding, a zero or even slightly negatively draft angle are aeptable. 6
7 Fig. 7: Different draft angle requirements. For a minimal draft angle γ, we an ompute τ = sin( γ ) and use it to replae 0 in Equations (2.2) and (3.27). Hene our optimization formulation an be hanged as: N d + N d + N d τ for fae F i, and xi x yi y zi z Λ( gi( )) + N(, β) di τ, i φ, ϕ. Aordingly, the omputed optimization solution, if any, will satisfy the given draft angle requirements. In addition, any non-drafted or under-drafted surfaes an be deteted if no solution is found for them. Notie, however, in our MIP formulation, only the demoldability requirement has been inorporated. We had diffiulties in onverting the fae onnetivity of a mold piee region into omputable formulation; hene suh onnetivity has not been inorporated. Hene, the optimal solution given by solving the MIP is atually a lower bound on the multi-piee mold design. That is, if without onsidering the onnetivity of mold piee regions, the minimum number of mold piees is found to be n (e.g. n= 5), it is impossible to find a better solution (i.e. n < 5) after the onnetivity of n mold piee regions has been onsidered. An example of suh onnetivity problem is shown in Figure 8. For a test part as shown in Figure 4, a minimum of three parting diretions has been identified after solving the MIP (i.e. d, d 2, and d 3 as shown in Figure 8). Aordingly three mold piee regions (m, m 2, and m 3 ) are required for them respetively. However, for a onave region (CVR ), its solution is d sine it has the biggest projetion areas in suh a diretion; nonetheless, CVR is not onneted to other regions that use the same parting diretion. 5. REFINING MULTI-PIECE MOLD DESIGN Based on the omputed parting diretions, we an eep on refining the generated mold piee regions suh that a mold design an be ahieved that is loser to the lower bound (n) instead of the upper bound (n+m). This an be done based on various heuristis. For example, we an ompute the projetion areas of eah onave region for the given parting β diretions (i.e. ). An example of suh results is Ai( Ni d) shown in Table for the test ase in Figure 8. In the table, a mar is assigned to a region if a related parting diretion annot satisfy the demoldability of the region. Parting TABLE THE PROJECTION AREA OF NINE CONCAVE REGIONS FOR TEST 3 Conave Region # (9 out of 2) Dirs d (0,0,-) d 2 (,0,0) d 3 (-,0,0) Hene, for CVR that is identified as isolated region in diretion d, we an he the other diretions d 2 and d 3. Sine they are both demoldable and onneted, we an reassign CVR to another mold piee region instead of adding a new one. Notie, as shown in Table, there are several onave regions that have a unique assignment to a related parting diretion. For example, CVR 3, CVR 4, and CVR 8 an only be assigned to d 3, d 2, and d respetively. We all suh onave regions as the ore onave regions of the related mold piee regions. Their assignments will not be hanged during the refining proess while other onave regions and onvex faes may be. In addition, we an also ompute a onnetivity table of all the hangeable onave regions and onvex faes based on the ore onave regions. In addition to demoldability and fae onnetivity, a wealth of mold design and manufaturing nowledge has been haraterized into a set of heuristis [~2]. These heuristis an also be onsidered in the proess of refining mold piee regions. For example, it is desired to have a smooth parting line. Hene for a mold design result generated by our system for test 3, whih is shown in Figure 9, we an further refine it by hanging the assignment of some faes for ahieving a smoother parting line (refer to red lines as shown in the figure). Fig. 8: An example of onnetivity of mold piee regions. Based on a set of given parting diretions, it is trivial to he the fae onnetivity between onave regions and identify all the isolated regions (suppose m of them are identified). Aordingly we have an upper bound on the multipiee mold design. That is, a solution must be able to found by using n+m mold piees after onsidering both demoldability and fae onnetivity requirements. Fig. 9: An example of inorporating mold design heuristis. 6. EXAMPLES Four test examples are given to illustrate our method. Test, 2, and 3 are shown in Figure 2, 5 and 3 respetively. Test 4 7
8 is shown in Figure 0. A summary of the omputed results is given in Table 2. The results were generated by solving the model desribed in Setion 3. The running time is based on a 3GHz Intel Xeon CPU using CPLEX 9.0. Test # Total Tri # TABLE 2 EXPERIMENTAL RESULTS OF FOUR TESTS Conave Region # Convex Fae # Resulted Parting Dir. # d, d 2 (0, 0, ), (0, 0, -) d, d 2 (0, 0, ), (0, -, 0) d,d 2,d 3 (0, 0, -), (, 0, 0), (-, 0, 0) d,d 2,d 3, d 4 (0,, 0), (0, 0, -), (-, 0, 0), (, 0, 0) Running Time (se) The largest problem we solved is test 4 whih has 86 onave regions and 250 onvex faes. CPLEX solved the linear MIP to optimality with a CPU time of 8.5 seonds inluding the omputation of both (d, d 2 ), (d, d 2, d 3 ) and (d, d 2, d 3, d 4 ). (a) (b) () Top View 86 onave regions d 4 Fig. 0: Sreen aptures of omputed results of test 4. d 3 4 mold piee regions 7. CONCLUSION For the multi-piee mold design of an arbitrary part model, we presented a novel approah by formulating a linear mixedinteger program based on a set of basi elements, onave regions and onvex faes. By using a state-of-the-art optimization solver, suh a problem an be solved for optimal d 2 Bottom View d solutions in reasonable time. Hene the optimality of multipiee mold design an be provided by identifying a lower and upper bound on the number of mold piees. The multiplepiee mold design an be further improved based on heuristis. Four examples were given and the test results have demonstrated the effetiveness and effiieny of our method. ACKNOWLEDGMENT We anowledge Prof. Satyandra K. Gupta at University of Maryland for providing us the part models of test 3 and 4. REFERENCES [] K. Hui, Geometri Aspets of the Mouldability of Parts, Computer-aided Design, 29(3), pp , 996. [2] T. Wong, S. T. Tan, and W. S. Sze. Parting line formation by sliing a 3D CAD model. Engineering with Computers, 4(4), pp , 998. [3] M. W. Fu, J. Y. H. Fuh, A. Y. C. Nee, Underut Feature Reognition in an Injetion Mould Design System, Computeraided Design, 3, pp , 999. [4] Z. Yin, H. Ding, Y. Xiong. Virtual prototyping of mold design: Geometri mouldability analysis for near-net-shape manufatured parts by feature reognition and geometri reasoning. Computer Aided Design, 33(2), pp , 200. [5] X. G. Ye, J. Y. H. Fuh, K. S. Lee. Automati Underut Feature Reognition for Side Core Design of Injetion Molds. Journal of Mehanial Design, 26, pp , [6] S. MMains, X. Chen. Finding underut-free parting diretions for polygons with urved edges. Journal of Computing and Information Siene in Engineering, 6(), pp , [7] R. Kharderar, G. Burton, and S. MMains. Finding feasible mold parting diretions using graphis hardware. Computer Aided Design, 38(4), pp , [8] Y. Chen, D. W. Rosen. A region based method to automated design of multi-piee molds with appliation to rapid tooling, Journal of Computing and Information Siene in Engineering, 2(2), pp , [9] Y. Chen, D. W. Rosen. A reverse glue approah to automated onstrution of multi-piee molds, Journal of Computing and Information Siene in Engineering, 3(3), pp , [0] A. Priyadarshi, S. K. Gupta. Geometri algorithms for automated design of multi-piee permanent molds. Computeraided Design, 36(3), pp , [] J. Huang, S. K. Gupta, K. Stoppel. Generating sarifiial multipiee molds using aessibility driven spatial partitioning. Computer-Aided Design, 35(3), pp , [2] A. K. Priyadarshi, S. K. Gupta. Algorithms for generating multistage molding plans for artiulated assemblies. Robotis and Computer Integrated Manufaturing, 32(3/4), pp , [3] L. L. Chen, S. Y. Chou, T. C. Woo. Parting diretions for mould and die design Computer-Aided Design, 25, pp , 993. [4] T. C. Woo, Visibility maps and spherial algorithms, Computer- Aided Design, 26(), pp. 6 6, 994. [5] S. Dhaliwal, S. K. Gupta, J. Huang, A. Priyadarshi. Algorithms for omputing global aessibility ones. Journal of Computing and Information Siene in Engineering,3(3), pp ,
Pipelined Multipliers for Reconfigurable Hardware
Pipelined Multipliers for Reonfigurable Hardware Mithell J. Myjak and José G. Delgado-Frias Shool of Eletrial Engineering and Computer Siene, Washington State University Pullman, WA 99164-2752 USA {mmyjak,
More informationApproximate logic synthesis for error tolerant applications
Approximate logi synthesis for error tolerant appliations Doohul Shin and Sandeep K. Gupta Eletrial Engineering Department, University of Southern California, Los Angeles, CA 989 {doohuls, sandeep}@us.edu
More informationThe Minimum Redundancy Maximum Relevance Approach to Building Sparse Support Vector Machines
The Minimum Redundany Maximum Relevane Approah to Building Sparse Support Vetor Mahines Xiaoxing Yang, Ke Tang, and Xin Yao, Nature Inspired Computation and Appliations Laboratory (NICAL), Shool of Computer
More informationLearning Convention Propagation in BeerAdvocate Reviews from a etwork Perspective. Abstract
CS 9 Projet Final Report: Learning Convention Propagation in BeerAdvoate Reviews from a etwork Perspetive Abstrat We look at the way onventions propagate between reviews on the BeerAdvoate dataset, and
More informationA Novel Validity Index for Determination of the Optimal Number of Clusters
IEICE TRANS. INF. & SYST., VOL.E84 D, NO.2 FEBRUARY 2001 281 LETTER A Novel Validity Index for Determination of the Optimal Number of Clusters Do-Jong KIM, Yong-Woon PARK, and Dong-Jo PARK, Nonmembers
More informationAbstract. Key Words: Image Filters, Fuzzy Filters, Order Statistics Filters, Rank Ordered Mean Filters, Channel Noise. 1.
Fuzzy Weighted Rank Ordered Mean (FWROM) Filters for Mixed Noise Suppression from Images S. Meher, G. Panda, B. Majhi 3, M.R. Meher 4,,4 Department of Eletronis and I.E., National Institute of Tehnology,
More informationDrawing lines. Naïve line drawing algorithm. drawpixel(x, round(y)); double dy = y1 - y0; double dx = x1 - x0; double m = dy / dx; double y = y0;
Naïve line drawing algorithm // Connet to grid points(x0,y0) and // (x1,y1) by a line. void drawline(int x0, int y0, int x1, int y1) { int x; double dy = y1 - y0; double dx = x1 - x0; double m = dy / dx;
More informationUsing Augmented Measurements to Improve the Convergence of ICP
Using Augmented Measurements to Improve the onvergene of IP Jaopo Serafin, Giorgio Grisetti Dept. of omputer, ontrol and Management Engineering, Sapienza University of Rome, Via Ariosto 25, I-0085, Rome,
More informationExtracting Partition Statistics from Semistructured Data
Extrating Partition Statistis from Semistrutured Data John N. Wilson Rihard Gourlay Robert Japp Mathias Neumüller Department of Computer and Information Sienes University of Strathlyde, Glasgow, UK {jnw,rsg,rpj,mathias}@is.strath.a.uk
More informationA Unified Subdivision Scheme for Polygonal Modeling
EUROGRAPHICS 2 / A. Chalmers and T.-M. Rhyne (Guest Editors) Volume 2 (2), Number 3 A Unified Subdivision Sheme for Polygonal Modeling Jérôme Maillot Jos Stam Alias Wavefront Alias Wavefront 2 King St.
More informationAdaptive Implicit Surface Polygonization using Marching Triangles
Volume 20 (2001), Number 2 pp. 67 80 Adaptive Impliit Surfae Polygonization using Marhing Triangles Samir Akkouhe Eri Galin L.I.G.I.M L.I.G.I.M Eole Centrale de Lyon Université Claude Bernard Lyon 1 B.P.
More informationAutomatic Physical Design Tuning: Workload as a Sequence Sanjay Agrawal Microsoft Research One Microsoft Way Redmond, WA, USA +1-(425)
Automati Physial Design Tuning: Workload as a Sequene Sanjay Agrawal Mirosoft Researh One Mirosoft Way Redmond, WA, USA +1-(425) 75-357 sagrawal@mirosoft.om Eri Chu * Computer Sienes Department University
More informationRotation Invariant Spherical Harmonic Representation of 3D Shape Descriptors
Eurographis Symposium on Geometry Proessing (003) L. Kobbelt, P. Shröder, H. Hoppe (Editors) Rotation Invariant Spherial Harmoni Representation of 3D Shape Desriptors Mihael Kazhdan, Thomas Funkhouser,
More informationOutline: Software Design
Outline: Software Design. Goals History of software design ideas Design priniples Design methods Life belt or leg iron? (Budgen) Copyright Nany Leveson, Sept. 1999 A Little History... At first, struggling
More informationDETECTION METHOD FOR NETWORK PENETRATING BEHAVIOR BASED ON COMMUNICATION FINGERPRINT
DETECTION METHOD FOR NETWORK PENETRATING BEHAVIOR BASED ON COMMUNICATION FINGERPRINT 1 ZHANGGUO TANG, 2 HUANZHOU LI, 3 MINGQUAN ZHONG, 4 JIAN ZHANG 1 Institute of Computer Network and Communiation Tehnology,
More informationGray Codes for Reflectable Languages
Gray Codes for Refletable Languages Yue Li Joe Sawada Marh 8, 2008 Abstrat We lassify a type of language alled a refletable language. We then develop a generi algorithm that an be used to list all strings
More informationCleanUp: Improving Quadrilateral Finite Element Meshes
CleanUp: Improving Quadrilateral Finite Element Meshes Paul Kinney MD-10 ECC P.O. Box 203 Ford Motor Company Dearborn, MI. 8121 (313) 28-1228 pkinney@ford.om Abstrat: Unless an all quadrilateral (quad)
More informationThe Happy Ending Problem
The Happy Ending Problem Neeldhara Misra STATUTORY WARNING This doument is a draft version 1 Introdution The Happy Ending problem first manifested itself on a typial wintery evening in 1933 These evenings
More informationVideo Data and Sonar Data: Real World Data Fusion Example
14th International Conferene on Information Fusion Chiago, Illinois, USA, July 5-8, 2011 Video Data and Sonar Data: Real World Data Fusion Example David W. Krout Applied Physis Lab dkrout@apl.washington.edu
More informationPlumber: a method for a multi-scale decomposition of 3D shapes into tubular primitives and bodies
ACM Symposium on Solid Modeling and Appliations (2004) P. Brunet, N. Patrikalakis (Editors) Plumber: a method for a multi-sale deomposition of 3D shapes into tubular primitives and bodies M. Mortara G.
More informationOn - Line Path Delay Fault Testing of Omega MINs M. Bellos 1, E. Kalligeros 1, D. Nikolos 1,2 & H. T. Vergos 1,2
On - Line Path Delay Fault Testing of Omega MINs M. Bellos, E. Kalligeros, D. Nikolos,2 & H. T. Vergos,2 Dept. of Computer Engineering and Informatis 2 Computer Tehnology Institute University of Patras,
More informationSmooth Trajectory Planning Along Bezier Curve for Mobile Robots with Velocity Constraints
Smooth Trajetory Planning Along Bezier Curve for Mobile Robots with Veloity Constraints Gil Jin Yang and Byoung Wook Choi Department of Eletrial and Information Engineering Seoul National University of
More informationNONLINEAR BACK PROJECTION FOR TOMOGRAPHIC IMAGE RECONSTRUCTION. Ken Sauer and Charles A. Bouman
NONLINEAR BACK PROJECTION FOR TOMOGRAPHIC IMAGE RECONSTRUCTION Ken Sauer and Charles A. Bouman Department of Eletrial Engineering, University of Notre Dame Notre Dame, IN 46556, (219) 631-6999 Shool of
More informationDetection and Recognition of Non-Occluded Objects using Signature Map
6th WSEAS International Conferene on CIRCUITS, SYSTEMS, ELECTRONICS,CONTROL & SIGNAL PROCESSING, Cairo, Egypt, De 9-31, 007 65 Detetion and Reognition of Non-Oluded Objets using Signature Map Sangbum Park,
More informationBoundary Correct Real-Time Soft Shadows
Boundary Corret Real-Time Soft Shadows Bjarke Jakobsen Niels J. Christensen Bent D. Larsen Kim S. Petersen Informatis and Mathematial Modelling Tehnial University of Denmark {bj, nj, bdl}@imm.dtu.dk, kim@deadline.dk
More informationUnsupervised Stereoscopic Video Object Segmentation Based on Active Contours and Retrainable Neural Networks
Unsupervised Stereosopi Video Objet Segmentation Based on Ative Contours and Retrainable Neural Networks KLIMIS NTALIANIS, ANASTASIOS DOULAMIS, and NIKOLAOS DOULAMIS National Tehnial University of Athens
More informationarxiv: v1 [cs.db] 13 Sep 2017
An effiient lustering algorithm from the measure of loal Gaussian distribution Yuan-Yen Tai (Dated: May 27, 2018) In this paper, I will introdue a fast and novel lustering algorithm based on Gaussian distribution
More informationPerformance of Histogram-Based Skin Colour Segmentation for Arms Detection in Human Motion Analysis Application
World Aademy of Siene, Engineering and Tehnology 8 009 Performane of Histogram-Based Skin Colour Segmentation for Arms Detetion in Human Motion Analysis Appliation Rosalyn R. Porle, Ali Chekima, Farrah
More informationHEXA: Compact Data Structures for Faster Packet Processing
Washington University in St. Louis Washington University Open Sholarship All Computer Siene and Engineering Researh Computer Siene and Engineering Report Number: 27-26 27 HEXA: Compat Data Strutures for
More informationTOWARD HYBRID VARIANT/GENERATIVE PROCESS PLANNING
Proeedings of DETC 97: 1997 ASME Design Engineering Tehnial Conferenes September 14-17,1997, Saramento, California DETC97/DFM-4333 TOWARD HYBRID VARIANT/GENERATIVE PROCESS PLANNING Alexei Elinson Dept.
More informationBoosted Random Forest
Boosted Random Forest Yohei Mishina, Masamitsu suhiya and Hironobu Fujiyoshi Department of Computer Siene, Chubu University, 1200 Matsumoto-ho, Kasugai, Aihi, Japan {mishi, mtdoll}@vision.s.hubu.a.jp,
More informationA DYNAMIC ACCESS CONTROL WITH BINARY KEY-PAIR
Malaysian Journal of Computer Siene, Vol 10 No 1, June 1997, pp 36-41 A DYNAMIC ACCESS CONTROL WITH BINARY KEY-PAIR Md Rafiqul Islam, Harihodin Selamat and Mohd Noor Md Sap Faulty of Computer Siene and
More informationParticle Swarm Optimization for the Design of High Diffraction Efficient Holographic Grating
Original Artile Partile Swarm Optimization for the Design of High Diffration Effiient Holographi Grating A.K. Tripathy 1, S.K. Das, M. Sundaray 3 and S.K. Tripathy* 4 1, Department of Computer Siene, Berhampur
More informationSparse Certificates for 2-Connectivity in Directed Graphs
Sparse Certifiates for 2-Connetivity in Direted Graphs Loukas Georgiadis Giuseppe F. Italiano Aikaterini Karanasiou Charis Papadopoulos Nikos Parotsidis Abstrat Motivated by the emergene of large-sale
More informationA Partial Sorting Algorithm in Multi-Hop Wireless Sensor Networks
A Partial Sorting Algorithm in Multi-Hop Wireless Sensor Networks Abouberine Ould Cheikhna Department of Computer Siene University of Piardie Jules Verne 80039 Amiens Frane Ould.heikhna.abouberine @u-piardie.fr
More informationKERNEL SPARSE REPRESENTATION WITH LOCAL PATTERNS FOR FACE RECOGNITION
KERNEL SPARSE REPRESENTATION WITH LOCAL PATTERNS FOR FACE RECOGNITION Cuiui Kang 1, Shengai Liao, Shiming Xiang 1, Chunhong Pan 1 1 National Laboratory of Pattern Reognition, Institute of Automation, Chinese
More informationGraph-Based vs Depth-Based Data Representation for Multiview Images
Graph-Based vs Depth-Based Data Representation for Multiview Images Thomas Maugey, Antonio Ortega, Pasal Frossard Signal Proessing Laboratory (LTS), Eole Polytehnique Fédérale de Lausanne (EPFL) Email:
More informationBatch Auditing for Multiclient Data in Multicloud Storage
Advaned Siene and Tehnology Letters, pp.67-73 http://dx.doi.org/0.4257/astl.204.50. Bath Auditing for Multilient Data in Multiloud Storage Zhihua Xia, Xinhui Wang, Xingming Sun, Yafeng Zhu, Peng Ji and
More informationAn Alternative Approach to the Fuzzifier in Fuzzy Clustering to Obtain Better Clustering Results
An Alternative Approah to the Fuzziier in Fuzzy Clustering to Obtain Better Clustering Results Frank Klawonn Department o Computer Siene University o Applied Sienes BS/WF Salzdahlumer Str. 46/48 D-38302
More informationChromaticity-matched Superimposition of Foreground Objects in Different Environments
FCV216, the 22nd Korea-Japan Joint Workshop on Frontiers of Computer Vision Chromatiity-mathed Superimposition of Foreground Objets in Different Environments Yohei Ogura Graduate Shool of Siene and Tehnology
More informationExploring the Commonality in Feature Modeling Notations
Exploring the Commonality in Feature Modeling Notations Miloslav ŠÍPKA Slovak University of Tehnology Faulty of Informatis and Information Tehnologies Ilkovičova 3, 842 16 Bratislava, Slovakia miloslav.sipka@gmail.om
More informationThe Implementation of RRTs for a Remote-Controlled Mobile Robot
ICCAS5 June -5, KINEX, Gyeonggi-Do, Korea he Implementation of RRs for a Remote-Controlled Mobile Robot Chi-Won Roh*, Woo-Sub Lee **, Sung-Chul Kang *** and Kwang-Won Lee **** * Intelligent Robotis Researh
More informationA Coarse-to-Fine Classification Scheme for Facial Expression Recognition
A Coarse-to-Fine Classifiation Sheme for Faial Expression Reognition Xiaoyi Feng 1,, Abdenour Hadid 1 and Matti Pietikäinen 1 1 Mahine Vision Group Infoteh Oulu and Dept. of Eletrial and Information Engineering
More informationthe data. Structured Principal Component Analysis (SPCA)
Strutured Prinipal Component Analysis Kristin M. Branson and Sameer Agarwal Department of Computer Siene and Engineering University of California, San Diego La Jolla, CA 9193-114 Abstrat Many tasks involving
More informationFUZZY WATERSHED FOR IMAGE SEGMENTATION
FUZZY WATERSHED FOR IMAGE SEGMENTATION Ramón Moreno, Manuel Graña Computational Intelligene Group, Universidad del País Vaso, Spain http://www.ehu.es/winto; {ramon.moreno,manuel.grana}@ehu.es Abstrat The
More informationOptimization of Two-Stage Cylindrical Gear Reducer with Adaptive Boundary Constraints
5 JOURNAL OF SOFTWARE VOL. 8 NO. 8 AUGUST Optimization of Two-Stage Cylindrial Gear Reduer with Adaptive Boundary Constraints Xueyi Li College of Mehanial and Eletroni Engineering Shandong University of
More informationSelf-Adaptive Parent to Mean-Centric Recombination for Real-Parameter Optimization
Self-Adaptive Parent to Mean-Centri Reombination for Real-Parameter Optimization Kalyanmoy Deb and Himanshu Jain Department of Mehanial Engineering Indian Institute of Tehnology Kanpur Kanpur, PIN 86 {deb,hjain}@iitk.a.in
More informationFuzzy Meta Node Fuzzy Metagraph and its Cluster Analysis
Journal of Computer Siene 4 (): 9-97, 008 ISSN 549-3636 008 Siene Publiations Fuzzy Meta Node Fuzzy Metagraph and its Cluster Analysis Deepti Gaur, Aditya Shastri and Ranjit Biswas Department of Computer
More information特集 Road Border Recognition Using FIR Images and LIDAR Signal Processing
デンソーテクニカルレビュー Vol. 15 2010 特集 Road Border Reognition Using FIR Images and LIDAR Signal Proessing 高木聖和 バーゼル ファルディ Kiyokazu TAKAGI Basel Fardi ヘンドリック ヴァイゲル Hendrik Weigel ゲルド ヴァニーリック Gerd Wanielik This paper
More informationA scheme for racquet sports video analysis with the combination of audio-visual information
A sheme for raquet sports video analysis with the ombination of audio-visual information Liyuan Xing a*, Qixiang Ye b, Weigang Zhang, Qingming Huang a and Hua Yu a a Graduate Shool of the Chinese Aadamy
More informationAbstract A method for the extrusion of arbitrary polygon meshes is introduced. This method can be applied to model a large class of complex 3-D
Abstrat A method for the extrusion of arbitrary polygon meshes is introdued. This method an be applied to model a large lass of omplex 3-D losed surfaes. It onsists of defining a (typially small) set of
More informationCluster-Based Cumulative Ensembles
Cluster-Based Cumulative Ensembles Hanan G. Ayad and Mohamed S. Kamel Pattern Analysis and Mahine Intelligene Lab, Eletrial and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1,
More informationCOMBINATION OF INTERSECTION- AND SWEPT-BASED METHODS FOR SINGLE-MATERIAL REMAP
Combination of intersetion- and swept-based methods for single-material remap 11th World Congress on Computational Mehanis WCCM XI) 5th European Conferene on Computational Mehanis ECCM V) 6th European
More informationCOST PERFORMANCE ASPECTS OF CCD FAST AUXILIARY MEMORY
COST PERFORMANCE ASPECTS OF CCD FAST AUXILIARY MEMORY Dileep P, Bhondarkor Texas Instruments Inorporated Dallas, Texas ABSTRACT Charge oupled devies (CCD's) hove been mentioned as potential fast auxiliary
More informationPartial Character Decoding for Improved Regular Expression Matching in FPGAs
Partial Charater Deoding for Improved Regular Expression Mathing in FPGAs Peter Sutton Shool of Information Tehnology and Eletrial Engineering The University of Queensland Brisbane, Queensland, 4072, Australia
More informationDirected Rectangle-Visibility Graphs have. Abstract. Visibility representations of graphs map vertices to sets in Euclidean space and
Direted Retangle-Visibility Graphs have Unbounded Dimension Kathleen Romanik DIMACS Center for Disrete Mathematis and Theoretial Computer Siene Rutgers, The State University of New Jersey P.O. Box 1179,
More informationA Fast Kernel-based Multilevel Algorithm for Graph Clustering
A Fast Kernel-based Multilevel Algorithm for Graph Clustering Inderjit Dhillon Dept. of Computer Sienes University of Texas at Austin Austin, TX 78712 inderjit@s.utexas.edu Yuqiang Guan Dept. of Computer
More informationStable Road Lane Model Based on Clothoids
Stable Road Lane Model Based on Clothoids C Gakstatter*, S Thomas**, Dr P Heinemann*, Prof Gudrun Klinker*** *Audi Eletronis Venture GmbH, **Leibniz Universität Hannover, ***Tehnishe Universität Münhen
More informationCalculation of typical running time of a branch-and-bound algorithm for the vertex-cover problem
Calulation of typial running time of a branh-and-bound algorithm for the vertex-over problem Joni Pajarinen, Joni.Pajarinen@iki.fi Otober 21, 2007 1 Introdution The vertex-over problem is one of a olletion
More informationNew Fuzzy Object Segmentation Algorithm for Video Sequences *
JOURNAL OF INFORMATION SCIENCE AND ENGINEERING 24, 521-537 (2008) New Fuzzy Obet Segmentation Algorithm for Video Sequenes * KUO-LIANG CHUNG, SHIH-WEI YU, HSUEH-JU YEH, YONG-HUAI HUANG AND TA-JEN YAO Department
More informationCluster Centric Fuzzy Modeling
10.1109/TFUZZ.014.300134, IEEE Transations on Fuzzy Systems TFS-013-0379.R1 1 Cluster Centri Fuzzy Modeling Witold Pedryz, Fellow, IEEE, and Hesam Izakian, Student Member, IEEE Abstrat In this study, we
More informationFast Elliptic Curve Algorithm of Embedded Mobile Equipment
Send Orders for Reprints to reprints@benthamsiene.net 8 The Open Eletrial & Eletroni Engineering Journal, 0, 7, 8-4 Fast Ellipti Curve Algorithm of Embedded Mobile Equipment Open Aess Lihong Zhang *, Shuqian
More informationAlgorithms for External Memory Lecture 6 Graph Algorithms - Weighted List Ranking
Algorithms for External Memory Leture 6 Graph Algorithms - Weighted List Ranking Leturer: Nodari Sithinava Sribe: Andi Hellmund, Simon Ohsenreither 1 Introdution & Motivation After talking about I/O-effiient
More informationGradient based progressive probabilistic Hough transform
Gradient based progressive probabilisti Hough transform C.Galambos, J.Kittler and J.Matas Abstrat: The authors look at the benefits of exploiting gradient information to enhane the progressive probabilisti
More informationAlgorithms, Mechanisms and Procedures for the Computer-aided Project Generation System
Algorithms, Mehanisms and Proedures for the Computer-aided Projet Generation System Anton O. Butko 1*, Aleksandr P. Briukhovetskii 2, Dmitry E. Grigoriev 2# and Konstantin S. Kalashnikov 3 1 Department
More informationMulti-Channel Wireless Networks: Capacity and Protocols
Multi-Channel Wireless Networks: Capaity and Protools Tehnial Report April 2005 Pradeep Kyasanur Dept. of Computer Siene, and Coordinated Siene Laboratory, University of Illinois at Urbana-Champaign Email:
More information3-D IMAGE MODELS AND COMPRESSION - SYNTHETIC HYBRID OR NATURAL FIT?
3-D IMAGE MODELS AND COMPRESSION - SYNTHETIC HYBRID OR NATURAL FIT? Bernd Girod, Peter Eisert, Marus Magnor, Ekehard Steinbah, Thomas Wiegand Te {girod eommuniations Laboratory, University of Erlangen-Nuremberg
More informationFast Rigid Motion Segmentation via Incrementally-Complex Local Models
Fast Rigid Motion Segmentation via Inrementally-Complex Loal Models Fernando Flores-Mangas Allan D. Jepson Department of Computer Siene, University of Toronto {mangas,jepson}@s.toronto.edu Abstrat The
More information2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media,
2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any urrent or future media, inluding reprinting/republishing this material for advertising
More informationAcoustic Links. Maximizing Channel Utilization for Underwater
Maximizing Channel Utilization for Underwater Aousti Links Albert F Hairris III Davide G. B. Meneghetti Adihele Zorzi Department of Information Engineering University of Padova, Italy Email: {harris,davide.meneghetti,zorzi}@dei.unipd.it
More informationColouring contact graphs of squares and rectilinear polygons de Berg, M.T.; Markovic, A.; Woeginger, G.
Colouring ontat graphs of squares and retilinear polygons de Berg, M.T.; Markovi, A.; Woeginger, G. Published in: nd European Workshop on Computational Geometry (EuroCG 06), 0 Marh - April, Lugano, Switzerland
More informationDr.Hazeem Al-Khafaji Dept. of Computer Science, Thi-Qar University, College of Science, Iraq
Volume 4 Issue 6 June 014 ISSN: 77 18X International Journal of Advaned Researh in Computer Siene and Software Engineering Researh Paper Available online at: www.ijarsse.om Medial Image Compression using
More informationExploiting Enriched Contextual Information for Mobile App Classification
Exploiting Enrihed Contextual Information for Mobile App Classifiation Hengshu Zhu 1 Huanhuan Cao 2 Enhong Chen 1 Hui Xiong 3 Jilei Tian 2 1 University of Siene and Tehnology of China 2 Nokia Researh Center
More informationAn Efficient and Scalable Approach to CNN Queries in a Road Network
An Effiient and Salable Approah to CNN Queries in a Road Network Hyung-Ju Cho Chin-Wan Chung Dept. of Eletrial Engineering & Computer Siene Korea Advaned Institute of Siene and Tehnology 373- Kusong-dong,
More informationSemi-Supervised Affinity Propagation with Instance-Level Constraints
Semi-Supervised Affinity Propagation with Instane-Level Constraints Inmar E. Givoni, Brendan J. Frey Probabilisti and Statistial Inferene Group University of Toronto 10 King s College Road, Toronto, Ontario,
More informationWhat are Cycle-Stealing Systems Good For? A Detailed Performance Model Case Study
What are Cyle-Stealing Systems Good For? A Detailed Performane Model Case Study Wayne Kelly and Jiro Sumitomo Queensland University of Tehnology, Australia {w.kelly, j.sumitomo}@qut.edu.au Abstrat The
More informationTrajectory Tracking Control for A Wheeled Mobile Robot Using Fuzzy Logic Controller
Trajetory Traking Control for A Wheeled Mobile Robot Using Fuzzy Logi Controller K N FARESS 1 M T EL HAGRY 1 A A EL KOSY 2 1 Eletronis researh institute, Cairo, Egypt 2 Faulty of Engineering, Cairo University,
More informationAccommodations of QoS DiffServ Over IP and MPLS Networks
Aommodations of QoS DiffServ Over IP and MPLS Networks Abdullah AlWehaibi, Anjali Agarwal, Mihael Kadoh and Ahmed ElHakeem Department of Eletrial and Computer Department de Genie Eletrique Engineering
More informationChapter 2: Introduction to Maple V
Chapter 2: Introdution to Maple V 2-1 Working with Maple Worksheets Try It! (p. 15) Start a Maple session with an empty worksheet. The name of the worksheet should be Untitled (1). Use one of the standard
More informationDefinitions Homework. Quine McCluskey Optimal solutions are possible for some large functions Espresso heuristic. Definitions Homework
EECS 33 There be Dragons here http://ziyang.ees.northwestern.edu/ees33/ Teaher: Offie: Email: Phone: L477 Teh dikrp@northwestern.edu 847 467 2298 Today s material might at first appear diffiult Perhaps
More informationCapturing Large Intra-class Variations of Biometric Data by Template Co-updating
Capturing Large Intra-lass Variations of Biometri Data by Template Co-updating Ajita Rattani University of Cagliari Piazza d'armi, Cagliari, Italy ajita.rattani@diee.unia.it Gian Lua Marialis University
More informationImproved Circuit-to-CNF Transformation for SAT-based ATPG
Improved Ciruit-to-CNF Transformation for SAT-based ATPG Daniel Tille 1 René Krenz-Bååth 2 Juergen Shloeffel 2 Rolf Drehsler 1 1 Institute of Computer Siene, University of Bremen, 28359 Bremen, Germany
More informationComparing Images Under Variable Illumination
( This paper appeared in CVPR 8. IEEE ) Comparing Images Under Variable Illumination David W. Jaobs Peter N. Belhumeur Ronen Basri NEC Researh Institute Center for Computational Vision and Control The
More informationContents Contents...I List of Tables...VIII List of Figures...IX 1. Introduction Information Retrieval... 8
Contents Contents...I List of Tables...VIII List of Figures...IX 1. Introdution... 1 1.1. Internet Information...2 1.2. Internet Information Retrieval...3 1.2.1. Doument Indexing...4 1.2.2. Doument Retrieval...4
More informationTransition Detection Using Hilbert Transform and Texture Features
Amerian Journal of Signal Proessing 1, (): 35-4 DOI: 1.593/.asp.1.6 Transition Detetion Using Hilbert Transform and Texture Features G. G. Lashmi Priya *, S. Domni Department of Computer Appliations, National
More informationScheduling Commercial Videotapes in Broadcast Television
Sheduling Commerial Videotapes in Broadast Television Srinivas Bollapragada bollapragada@researh.ge.om GE Global Researh Center 1 Researh Cirle, Shenetady, NY 12309 Mihael Bussiek MBussiek@gams.om GAMS
More informationReal-time Container Transport Planning with Decision Trees based on Offline Obtained Optimal Solutions
Real-time Container Transport Planning with Deision Trees based on Offline Obtained Optimal Solutions Bart van Riessen vanriessen@ese.eur.nl Eonometri Institute Erasmus Shool of Eonomis Erasmus University
More informationChemical, Biological and Radiological Hazard Assessment: A New Model of a Plume in a Complex Urban Environment
hemial, Biologial and Radiologial Haard Assessment: A New Model of a Plume in a omplex Urban Environment Skvortsov, A.T., P.D. Dawson, M.D. Roberts and R.M. Gailis HPP Division, Defene Siene and Tehnology
More informationDynamic Programming. Lecture #8 of Algorithms, Data structures and Complexity. Joost-Pieter Katoen Formal Methods and Tools Group
Dynami Programming Leture #8 of Algorithms, Data strutures and Complexity Joost-Pieter Katoen Formal Methods and Tools Group E-mail: katoen@s.utwente.nl Otober 29, 2002 JPK #8: Dynami Programming ADC (214020)
More informationEvolutionary Feature Synthesis for Image Databases
Evolutionary Feature Synthesis for Image Databases Anlei Dong, Bir Bhanu, Yingqiang Lin Center for Researh in Intelligent Systems University of California, Riverside, California 92521, USA {adong, bhanu,
More informationCell Projection of Convex Polyhedra
Volume Graphis (2003) I. Fujishiro, K. Mueller, A. Kaufman (Editors) Cell Projetion of Convex Polyhedra Stefan Roettger and Thomas Ertl Visualization and Interative Systems Group University of Stuttgart
More informationDefect Detection and Classification in Ceramic Plates Using Machine Vision and Naïve Bayes Classifier for Computer Aided Manufacturing
Defet Detetion and Classifiation in Cerami Plates Using Mahine Vision and Naïve Bayes Classifier for Computer Aided Manufaturing 1 Harpreet Singh, 2 Kulwinderpal Singh, 1 Researh Student, 2 Assistant Professor,
More informationConstructing Transaction Serialization Order for Incremental. Data Warehouse Refresh. Ming-Ling Lo and Hui-I Hsiao. IBM T. J. Watson Research Center
Construting Transation Serialization Order for Inremental Data Warehouse Refresh Ming-Ling Lo and Hui-I Hsiao IBM T. J. Watson Researh Center July 11, 1997 Abstrat In typial pratie of data warehouse, the
More informationMethods for Multi-Dimensional Robustness Optimization in Complex Embedded Systems
Methods for Multi-Dimensional Robustness Optimization in Complex Embedded Systems Arne Hamann, Razvan Rau, Rolf Ernst Institute of Computer and Communiation Network Engineering Tehnial University of Braunshweig,
More informationSystem-Level Parallelism and Throughput Optimization in Designing Reconfigurable Computing Applications
System-Level Parallelism and hroughput Optimization in Designing Reonfigurable Computing Appliations Esam El-Araby 1, Mohamed aher 1, Kris Gaj 2, arek El-Ghazawi 1, David Caliga 3, and Nikitas Alexandridis
More informationA {k, n}-secret Sharing Scheme for Color Images
A {k, n}-seret Sharing Sheme for Color Images Rastislav Luka, Konstantinos N. Plataniotis, and Anastasios N. Venetsanopoulos The Edward S. Rogers Sr. Dept. of Eletrial and Computer Engineering, University
More informationPERSISTENT NAMING FOR PARAMETRIC MODELS
PERSISTENT NAMING FOR PARAMETRIC MODELS Dago AGBODAN, David MARCHEIX and Guy PIERRA Laboratory of Applied Computer Siene (LISI) National Shool of Engineers in Mehanis and Aeronautis (ENSMA) Téléport 2
More informationCross-layer Resource Allocation on Broadband Power Line Based on Novel QoS-priority Scheduling Function in MAC Layer
Communiations and Networ, 2013, 5, 69-73 http://dx.doi.org/10.4236/n.2013.53b2014 Published Online September 2013 (http://www.sirp.org/journal/n) Cross-layer Resoure Alloation on Broadband Power Line Based
More information1. Introduction. 2. The Probable Stope Algorithm
1. Introdution Optimization in underground mine design has reeived less attention than that in open pit mines. This is mostly due to the diversity o underground mining methods and omplexity o underground
More informationDeep Rule-Based Classifier with Human-level Performance and Characteristics
Deep Rule-Based Classifier with Human-level Performane and Charateristis Plamen P. Angelov 1,2 and Xiaowei Gu 1* 1 Shool of Computing and Communiations, Lanaster University, Lanaster, LA1 4WA, UK 2 Tehnial
More information