Canonical Generalized Inversion Form of Kane’s Equations of Motion for Constrained Mechanical Systems

The canonical generalized inversion dynamical equations of motion for ideally constrained discrete mechanical systems are introduced in the framework of Kane’s method. The canonical equations of motion employ the acceleration form of constraints and the Moore-Penrose generalized inversion-based Greville formula for general solutions of linear systems of algebraic equations. Moreover, the canonical equations of motion are explicit and nonminimal (full order) in the acceleration variables, and their derivation is made without appealing to the principle of virtual work or to Lagrange multipliers. The geometry of constrained motion is revealed by the canonical equations of motion in a clear and intuitive manner by partitioning the canonical accelerations’ column matrix into two portions: a portion that drives the mechanical system to abide by the constraints and a portion that generates the momentum balance dynamics of the mechanical system. Some geometrical perspectives of the canonical equations of motion are illustrated via vectorial geometric visualization, which leads to verifying the Gauss’ principle of least constraints and its Udwadia-Kalaba interpretation

Corrigendum: New Form of Kane's Equations of Motion for Constrained Systems

A correction to the previously published article "New Form of Kane's Equations of Motion for Constrained Systems" is presented. Misuse of the transformation matrix between time rates of change of the generalized coordinates and generalized speeds (sometimes called motion variables) resulted in a false conclusion concerning the symmetry of the generalized inertia matrix. The generalized inertia matrix (sometimes referred to as the mass matrix) is in fact symmetric and usually positive definite when one forms nonminimal Kane's equations for holonomic or simple nonholonomic systems, systems subject to nonlinear nonholonomic constraints, and holonomic or simple nonholonomic systems subject to impulsive constraints according to Refs. 1, 2, and 3, respectively. The mass matrix is of course symmetric when one forms minimal equations for holonomic or simple nonholonomic systems using Kane s method as set forth in Ref. 4

ICMA 2002: proceedings of the International Conference on Manufacturing Automation : Rapid Response Solutions to Product Development, December 10-12, 2002, Hong Kong, China

Includes bibliographical references and index.published_or_final_versionStereo-thermal-lithography - a new principle for rapid prototyping P. Bartolo Bartolo, P. G. Mitchell Mitchell, G. 459Rapid tooling - producing functional metal parts from fused deposition modelling process using plaster moulding R. Narain Narain, R. A. Srivastava Srivastava, A. 451Systematic approach for modelling the superplastic deformation process of 2024AI alloys under constant strain rate - use of FE technique O. F. Yenihayat Yenihayat, O. F. H. Unal Unal, H. A. Mimaroglu Mimaroglu, A. A. Ozel Ozel, A. 107Design animation for rapid product development G. Liu Liu, G. H. T. Loh Loh, H. T. A. C. Brombacher Brombacher, A. C. H. S. Tan Tan, H. S. 99Image-based modelling for reverse engineering of large objects N. M. Alves Alves, N. M. P. J. S. Bartolo Bartolo, P. J. S. J. C. Ferreira Ferreira, J. C. 91Collaborative integrated planning for managing product rollovers in Internet-enabled supply chains R. Gaonkar Gaonkar, R. N. Viswanadham Viswanadham, N. 527Towards a systematic theory of axiomatic design review (STAR) G. Q. Huang Huang, G. Q. Z. H. Jiang Jiang, Z. H. 83Enhancing conceptual CAD interface by haptic feedback and two-handed input G. Zhan Zhan, G. I. Gibson Gibson, I. 73A modelling method of heterogeneous components K.-Z. Chen Chen, K.-Z. X.-A. Feng Feng, X.-A. 65Heterogeneous materials and their applications in high- tech production design X.-J. Zhang Zhang, X.-J. K.-Z. Chen Chen, K.-Z. 57Collaborative part manufacturing via an online e-service platform P. Jiang Jiang, P. Y. Zhang Zhang, Y. H. Sun Sun, H. 519Development platform for networked sale and customization systems Y. Yang Yang, Y. X. Zhang Zhang, X. F. Liu Liu, F. S. Liu Liu, S. 511The virtual design system for individualized product based on Internet T. Zheng Zheng, T. Y. He He, Y. 503The rapid tooling testbed - a distributed design-for- manufacturing system D. W. Rosen Rosen, D. W. J. K. Allen Allen, J. K. F. Mistree Mistree, F. Y. Chen Chen, Y. S. Sambu Sambu, S. 491Exact G[superscript 1] continuity conditions of B-spline surfaces with applications for multiple surface fitting W. Ma Ma, W. N. Zhao Zhao, N. 47Rapid prototyping of a differential housing using three- dimensional printing technology D. Dimitrov Dimitrov, D. K. Schreve Schreve, K. 483Authors' Index 543Rapid manufacturing - technologies and applications D. T. Pham Pham, D. T. S. S. Dimov Dimov, S. S. 3Process parameter optimization using a feed-forward neural network for direct metal laser sintering process Y. Ning Ning, Y. J. Y. H. Fuh Fuh, J. Y. H. Y. S. Wong Wong, Y. S. H. T. Loh Loh, H. T. 475Benchmarking for decision support in RP systems M. Mahesh Mahesh, M. Y. S. Wong Wong, Y. S. J. Y. H. Fuh Fuh, J. Y. H. H. T. Loh Loh, H. T. 467Risk mitigation investment in concurrent design process S. Amornsawadwatana Amornsawadwatana, S. A. Ahmed Ahmed, A. B. Kayis Kayis, B. H. Kaebernick Kaebernick, H. 23Development of CAD/CAM environment for one-of-a-kind production K. Lappalainen Lappalainen, K. 39Discrete adaptive mesh based on behaviour constrain of dynamic particles for three-dimensional reconstruction W. Yang Yang, W. W. Hu Hu, W. Y. Xiong Xiong, Y. 31Develop a process planning model for layer-based machining Z. Y. Yang Yang, Z. Y. Y. H. Chen Chen, Y. H. W. S. Sze Sze, W. S. 441A new fused deposition rapid prototyping machine S. Zhang Zhang, S. G. Liu Liu, G. 433Numerical simulation of direct metal laser sintering process W. Jiang Jiang, W. K. W. Dalgarno Dalgarno, K. W. T. H. C. Childs Childs, T. H. C. 425The research of the biomaterials' rapid forming machines Y. Yan Yan, Y. R. Wu Wu, R. L. Chen Chen, L. W. Zheng Zheng, W. 419The research of the SLS process optimization based on the hybrid of neural network and expert system Y. Shi Shi, Y. J. Liu Liu, J. D. Cai Cai, D. S. Huang Huang, S. 409Research and implementation of framework for selective laser sintering system of low cost J. Xie Xie, J. Y. Shi Shi, Y. S. Huang Huang, S. Z. Duan Duan, Z. 399The research of a self-adapting delaminating algorithm based on profile loop and its application to rapid prototyping system D. Cai Cai, D. Y. Shi Shi, Y. S. Huang Huang, S. 389Application of rapid prototyping to fabrication of casting mould Y. Shi Shi, Y. X. Lu Lu, X. N. Huang Huang, N. S. Huang Huang, S. 379MEM technology in making human skull-absent substitutes G.-X. Tang Tang, G.-X. R. Zhang Zhang, R. Y. Yan Yan, Y. 373The cutting stock problem in make-to-order small/medium enterprises F. Connolly Connolly, F. C. Sheahan Sheahan, C. 357A purchasing policy model based on components/parts unification X. Sun Sun, X. D. Man Man, D. D. Zhong Zhong, D. 347Research on the process model of product development with uncertainty based on activity overlapping R. Xiao Xiao, R. S. Si Si, S. 337Research on virtual/practical integrated material processing cell H. Bin Bin, H. F. Xiong Xiong, F. J. Yang Yang, J. 329A hierarchical approach to assembly sequence planning X. Niu Niu, X. H. Ding Ding, H. Y. Xiong Xiong, Y. 321Some issues in LCA for manufacturing industries C. Deng Deng, C. P. Li Li, P. 315Dynamic management of assembly constraints for virtual disassembly P. Cao Cao, P. J. Liu Liu, J. Y. Zhong Zhong, Y. 306Flexibility management and measurement of flexibility in Australian manufacturing industry B. Kayis Kayis, B. K. Skutalakul Skutalakul, K. 299Quality function deployment - how it can be extended to incorporate green engineering objectives H. K. Wong Wong, H. K. J. Juniper Juniper, J. 291Application of genetic algorithm to computer-aided process planning in distributed manufacturing systems L. Li Li, L. J. Y. H. Fuh Fuh, J. Y. H. Y. F. Zhang Zhang, Y. F. A. Y. C. Nee Nee, A. Y. C. 281Incremental induction based on logical network R.-L. Sun Sun, R.-L. Y. Xiong Xiong, Y. H. Ding Ding, H. 273Integrating intelligent agents with legacy manufacturing information systems C. W. Leung Leung, C. W. T. N. Wong Wong, T. N. 265Agent-based control of a flexible assembly cell C. K. Fan Fan, C. K. T. N. Wong Wong, T. N. 257An application of expert system in manufacturing - a case study H. K. Wong Wong, H. K. 249A machining feature extraction approach for casting and forging parts B. F. Wang Wang, B. F. Y. F. Zhang Zhang, Y. F. J. Y. H. Fuh Fuh, J. Y. H. 237Analytical approach for selection of optimal feedrate in efficient machining of complex surfaces G. Vikram Vikram, G. P. Harsha Harsha, P. N. R. Babu Babu, N. R. 227Modelling cutter swept angle at cornering cut H. S. Choy Choy, H. S. K. W. Chan Chan, K. W. 215The geometrical theory of machining free form surface by cylindrical cutter in five-axis NC machine tools L. X. Cao Cao, L. X. H. J. Wu Wu, H. J. J. Liu Liu, J. 205Parallelly generating NC tool paths for subdivision surfaces J. Dai Dai, J. K. Qin Qin, K. 195A study and mathematic proof on the tool feed direction for each tool motion with the maximum efficiency in three- axis sculptured surface machining Z. C. Chen Chen, Z. C. Z. Dong Dong, Z. G. W. Vickers Vickers, G. W. 179Intelligent process planning system for optimal CNC programming - a step towards complete automation of CNC programming M. K. Yeung Yeung, M. K. 169Development of a dynamic web-based graphing tool P. Lin Lin, P. R. Eappen Eappen, R. 535Radial force and hole oversize prediction in drilling using traditional and neural networks V. Karri Karri, V. T. Kiatcharoenpol Kiatcharoenpol, T. 159A new approach for addition of draft angles on well- rounded polyhedral Y. Yan Yan, Y. S. T. Tan Tan, S. T. 145The effective way of doing computer-aided reverse engineering I. E. Popov Popov, I. E. F. M. M. Chan Chan, F. M. M. 137A three-dimensional surface offset method for STL-format models X. Qu Qu, X. B. Stucker Stucker, B. 127Computer-aided design methods for additive fabrication of truss structures H. Wang Wang, H. D. W. Rosen Rosen, D. W. 11

DNA topoisomerases participate in fragility of the oncogene RET

Fragile site breakage was previously shown to result in rearrangement of the RET oncogene, resembling the rearrangements found in thyroid cancer. Common fragile sites are specific regions of the genome with a high susceptibility to DNA breakage under conditions that partially inhibit DNA replication, and often coincide with genes deleted, amplified, or rearranged in cancer. While a substantial amount of work has been performed investigating DNA repair and cell cycle checkpoint proteins vital for maintaining stability at fragile sites, little is known about the initial events leading to DNA breakage at these sites. The purpose of this study was to investigate these initial events through the detection of aphidicolin (APH)-induced DNA breakage within the RET oncogene, in which 144 APHinduced DNA breakpoints were mapped on the nucleotide level in human thyroid cells within intron 11 of RET, the breakpoint cluster region found in patients. These breakpoints were located at or near DNA topoisomerase I and/or II predicted cleavage sites, as well as at DNA secondary structural features recognized and preferentially cleaved by DNA topoisomerases I and II. Co-treatment of thyroid cells with APH and the topoisomerase catalytic inhibitors, betulinic acid and merbarone, significantly decreased APH-induced fragile site breakage within RET intron 11 and within the common fragile site FRA3B. These data demonstrate that DNA topoisomerases I and II are involved in initiating APH-induced common fragile site breakage at RET, and may engage the recognition of DNA secondary structures formed during perturbed DNA replication

Polymorphism in COX-2 modifies the inverse association between Helicobacter pylori seropositivity and esophageal squamous cell carcinoma risk in Taiwan: a case control study

<p>Abstract</p> <p>Background</p> <p>Overexpression of Cyclooxygenase-2 (COX-2) was observed in many types of cancers, including esophageal squamous cell carcinoma (ESCC). One functional SNP, COX-2 -1195G/A, has been reported to mediate susceptibility of ESCC in Chinese populations. In our previous study, the presence of <it>Helicobacter pylori </it>(<it>H. pylori</it>) was found to play a protective role in development of ESCC. The interaction of COX-2 and <it>H. pylori </it>in gastric cancer was well investigated. However, literature on their interaction in ESCC risk is scarce. The purpose of this study was to evaluate the association and interaction between COX-2 single nucleotide polymorphism (SNP), <it>H. pylori </it>infection and the risk of developing ESCC.</p> <p>Methods</p> <p>One hundred and eighty patients with ESCC and 194 controls were enrolled in this study. Personal data regarding related risk factors, including alcohol consumption, smoking habits and betel quid chewing, were collected via questionnaire. Genotypes of the COX-2 -1195 polymorphism were determined by PCR-based restriction fragment length polymorphism. <it>H. pylori </it>seropositivity was defined by immunochromatographic screening test. Data was analyzed by chi-squared tests and polytomous logistics regression.</p> <p>Results</p> <p>In analysis adjusting for the covariates and confounders, <it>H. pylori </it>seropositivity was found to be inversely association with the ESCC development (adjusted OR: 0.5, 95% CI: 0.3 – 0.9). COX-2 -1195 AA homozygous was associated with an increased risk of contracting ESCC in comparison with the non-AA group, especially among patients with <it>H. pylori </it>seronegative (adjusted OR ratio: 2.9, 95% CI: 1.2 – 7.3). The effect was strengthened among patients with lower third ESCC (adjusted OR ratio: 6.9, 95% CI 2.1 – 22.5). Besides, <it>H. pylori </it>seropositivity conveyed a notably inverse effect among patients with COX-2 AA polymorphism (AOR ratio: 0.3, 95% CI: 0.1 – 0.9), and the effect was observed to be enhanced for the lower third ESCC patients (AOR ratio: 0.09, 95% CI: 0.02 – 0.47, <it>p </it>for multiplicative interaction 0.008)</p> <p>Conclusion</p> <p><it>H. pylori </it>seropositivity is inversely associated with the risk of ESCC in Taiwan, and COX-2 -1195 polymorphism plays a role in modifying the influence between <it>H. pylori </it>and ESCC, especially in lower third esophagus.</p

Urine tests for Down's syndrome screening

Background Down's syndrome occurs when a person has three copies of chromosome 21, or the specific area of chromosome 21 implicated in causing Down's syndrome, rather than two. It is the commonest congenital cause of mental disability and also leads to numerous metabolic and structural problems. It can be life-threatening, or lead to considerable ill health, although some individuals have only mild problems and can lead relatively normal lives. Having a baby with Down's syndrome is likely to have a significant impact on family life. The risk of a Down's syndrome affected pregnancy increases with advancing maternal age. Noninvasive screening based on biochemical analysis of maternal serum or urine, or fetal ultrasound measurements, allows estimates of the risk of a pregnancy being affected and provides information to guide decisions about definitive testing. Before agreeing to screening tests, parents need to be fully informed about the risks, benefits and possible consequences of such a test. This includes subsequent choices for further tests they may face, and the implications of both false positive and false negative screening tests (i.e. invasive diagnostic testing, and the possibility that a miscarried fetus may be chromosomally normal). The decisions that may be faced by expectant parents inevitably engender a high level of anxiety at all stages of the screening process, and the outcomes of screening can be associated with considerable physical and psychological morbidity. No screening test can predict the severity of problems a person with Down's syndrome will have. Objectives To estimate and compare the accuracy of first and second trimester urine markers for the detection of Down's syndrome. Search methods We carried out a sensitive and comprehensive literature search of MEDLINE (1980 to 25 August 2011), EMBASE (1980 to 25 August 2011), BIOSIS via EDINA (1985 to 25 August 2011), CINAHL via OVID (1982 to 25 August 2011), The Database of Abstracts of Reviews of Effectiveness (The Cochrane Library 2011, Issue 7), MEDION (25 August 2011), The Database of Systematic Reviews and Meta-Analyses in Laboratory Medicine (25 August 2011), The National Research Register (archived 2007), Health Services Research Projects in Progress database (25 August 2011). We studied reference lists and published review articles. Selection criteria Studies evaluating tests of maternal urine in women up to 24 weeks of gestation for Down's syndrome, compared with a reference standard, either chromosomal verification or macroscopic postnatal inspection. Data collection and analysis We extracted data as test positive or test negative results for Down's and non-Down's pregnancies allowing estimation of detection rates (sensitivity) and false positive rates (1-specificity). We performed quality assessment according to QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria. We used hierarchical summary ROC (receiver operating characteristic) meta-analytical methods to analyse test performance and compare test accuracy. We performed analysis of studies allowing direct comparison between tests. We investigated the impact of maternal age on test performance in subgroup analyses. Main results We included 19 studies involving 18,013 pregnancies (including 527 with Down's syndrome). Studies were generally of high quality, although differential verification was common with invasive testing of only high-risk pregnancies. Twenty-four test combinations were evaluated formed from combinations of the following seven different markers with and without maternal age: AFP (alpha-fetoprotein), ITA (invasive trophoblast antigen), ß-core fragment, free ßhCG (beta human chorionic gonadotrophin), total hCG, oestriol, gonadotropin peptide and various marker ratios. The strategies evaluated included three double tests and seven single tests in combination with maternal age, and one triple test, two double tests and 11 single tests without maternal age. Twelve of the 19 studies only evaluated the performance of a single test strategy while the remaining seven evaluated at least two test strategies. Two marker combinations were evaluated in more than four studies; second trimester ß-core fragment (six studies), and second trimester ß-core fragment with maternal age (five studies). In direct test comparisons, for a 5% false positive rate (FPR), the diagnostic accuracy of the double marker second trimester ß-core fragment and oestriol with maternal age test combination was significantly better (ratio of diagnostic odds ratio (RDOR): 2.2 (95% confidence interval (CI) 1.1 to 4.5), P = 0.02) (summary sensitivity of 73% (CI 57 to 85) at a cut-point of 5% FPR) than that of the single marker test strategy of second trimester ß-core fragment and maternal age (summary sensitivity of 56% (CI 45 to 66) at a cut-point of 5% FPR), but was not significantly better (RDOR: 1.5 (0.8 to 2.8), P = 0.21) than that of the second trimester ß-core fragment to oestriol ratio and maternal age test strategy (summary sensitivity of 71% (CI 51 to 86) at a cut-point of 5% FPR). Authors' conclusions Tests involving second trimester ß-core fragment and oestriol with maternal age are significantly more sensitive than the single marker second trimester ß-core fragment and maternal age, however, there were few studies. There is a paucity of evidence available to support the use of urine testing for Down's syndrome screening in clinical practice where alternatives are available

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe