bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensory Irritating Effects of Allyl Halides and a Role for Hydrogen Bonding as a Likely Feature at the Receptor Site
Authors: Nielsen G. D. , Bakbo J. C.
Published: July 2010

Abstract: Allyl chloride, bromide and iodide were investigated for their properties as sensory irritants in mice. The concentrations of the chemicals necessary to depress the respiratory rate by 50% (RD50) within the first 10 min. of exposure due to irritation of the upper respiratory tract were 2330, 257 and 79.8 p.p.m., respectively. No pulmonary irritation was observed. In the period 20 to 30 min., however, pulmonary irritation was observed for allyl bromide and iodide. The effect was not prominent in non–cannulated mice probably due to the scrubbing effect of the nose. According to RD50 values, thermodynamic activity as well as apparent association rate with the receptor the sensory irritating potencies of the halides were low compared to those of allyl alcohol, acetate, and ether. A mechanistic explanation could not be ascribed to metabolites, lipophilicity or chemical reactivity. Only a hydrogen bond donor ability of the receptor offered an explanation. As many industrial chemicals e.g. alcohols, ketones and esters can function as hydrogen bond acceptors this receptor–feature cannot be overemphasized
Morphine Antidiuresis in Conscious Rats: Contribution of Vasopressin and Blood Pressure *
Authors: Grell S. , Christensen J. Dencker , Fjalland B.
Published: July 2010

Intracerebroventricular injections of morphine (5–20 μg) produced a dose dependent antidiuresis in the conscious hydrated rat. Naloxone pretreatment completely abolished this antidiuretic effect, but pretreatment with a specific antidiuretic vasopressin antagonist did not change the morphine antidiuresis. The vasopressin concentration in the first voided urine after antidiuresis from morphine treated rats was found to be in the same range as the vasopressin concentration in urine from saline treated rats. Injections of 20 μg morphine intracerebroventricularly in conscious hydrated rats gave a short decrease in heart rate but not in mean arterial blood pressure. This indicates, that either liberation of vasopressin nor a fall in systemic blood pressure contribute to the morphine antidiuresis.
Tissue Level Related Stereotyped Behaviour after Intravenous Amphetamine in Rats
Authors: Dahl Carl Bredo , Götestam K. Gunnar
Published: July 2010

Abstract:In the first experiment, open field activity was studied in rats after different intravenous doses of d‐amphetamine (0.5, 2, 4, 6, 8 mg/kg) at three time points (1–5, 28–32, 58–62 min.). Ambulation and rearing initially increased with increasing amphetamine doses, but at 8 mg/kg the registered activity was replaced by stereotyped disintegrated behaviour. In the second experiment plasma and brain levels of d‐amphetamine were determined (at 3, 30 and 60 min.) after 5 different intravenous doses of d‐amphetamine (0.25, 0.5, 2, 4, 8 mg/kg). Ambulation and rearing where then plotted against the tissue levels. There was initially a positive correlation between activity and tissue level. At a certain level a maximum was reached, followed by a decline with increasing tissue levels. At 3 min., the decline started after 15 μg/g of amphetamine in the brain tissue, at 30 min. this level was 3, and at 60 min. 2 μg/g. It is concluded that at least 5 times higher brain concentrations are needed to elicit stereotyped behaviour, than to maintain it later on.
Effect of Zinc Pyridinethione on the Tissue Disposition of Nickel and Cadmium in Mice
Authors: Jasim Suhair , Tjälve Hans
Published: July 2010

Abstract: Oral administration of zinc pyridinethione together with 63Ni2+ or 109Cd2+ to mice resulted in increased levels of these metals in several tissues in comparison with animals given the metals alone. The disposition of the 63Ni2+ was affected more than the disposition of the 109Cd2+. Increased urinary excretion of the metals was also induced by the zinc pyridinethione. Determinations of chloroform: water partition coefficients showed that lipophilic complexes are formed at equilibrations between Ni2+ or Cd2+ and zinc pyridinethione. A facilitated penetration of the lipophilic metal complexes thorugh the cellular membranes in the gastrointestinal tract and in other tissues is probably important for the observed results. Our data suggest that effects on the disposition of metals may play a role for the toxicity of zinc pyridinethione.
Evolution and Function of the Uterine Serpins (SERPINA14)
Authors: Padua Maria B. , Hansen Peter J.
Published: July 2010

Citation Padua MB, Hansen PJ. Evolution and function of the uterine serpins (SERPINA14). Am J Reprod Immunol 2010

Uterine serpins (recently designated as SERPINA14) are hormonally induced proteins secreted in large quantities by the endometrial epithelium during pregnancy. The SERPINA14 proteins belong to the serine proteinase inhibitor (serpin) superfamily, but their apparent lack of inhibitory activity toward serine proteinases suggests that these proteins evolved a different function from the anti‐proteinase activity typically found in most members of the serpin superfamily. The gene is present in a limited group of mammals in the Laurasiatheria superorder (ruminants, horses, pigs, dolphins and some carnivores) while being absent in primates, rodents, lagomorphs and marsupials. Thus, the gene is likely to have evolved by gene duplication after divergence of Laurasiatheria and to play an important role in pregnancy. That role may vary between species. In sheep, SERPINA14 probably serves an immunoregulatory role to prevent rejection of the fetal allograft. It is inhibitory to lymphocyte proliferation and natural killer cell function. In the pig, SERPINA14 is involved in iron transport to the fetus by binding to and stabilizing the iron‐binding protein uteroferrin. It is possible that SERPINA14 has undergone divergence in function since the original emergence of the gene in a common ancestor of species possessing SERPINA14.
Maternal and Fetal Response to Fetal Persistent Infection with Bovine Viral Diarrhea Virus*
Authors: Hansen Thomas R. , Smirnova Natalia P. , Van Campen Hana , Shoemaker Megan L. , Ptitsyn Andrey A. , Bielefeldt‐Ohmann Helle
Published: July 2010

Citation Hansen TR, Smirnova NP, Van Campen H, Shoemaker ML, Ptitsyn AA, Bielefeldt‐Ohmann H. Maternal and fetal response to fetal persistent infection with bovine viral diarrhea virus. Am J Reprod Immunol 2010

Problem  Infection of naïve pregnant cows with non‐cytopathic (ncp) bovine viral diarrhea virus (BVDV) results in transplacental infection of the fetus. Infection of the pregnant cow with ncp BVDV late in gestation (after day 150) results in transient infection (TI), as both the dam and fetus can mount an immune response to the virus. In contrast, if the fetus is infected with ncp BVDV early in gestation (before day 150), the fetal immune system is undeveloped and unable to recognize the virus as foreign. This results in induction of immune tolerance to the infecting BVDV strain and persistent infection (PI).

Methods  Infection of naïve pregnant heifers with ncp BVDV2 on day 75 was hypothesized to induce differential gene expression in white blood cells of the dams and their fetuses, adversely affecting development and antiviral immune responses in PI fetuses.

Results  Gene expression differed in maternal blood cells in the presence of PI versus uninfected fetuses. PI adversely affected fetal development and antiviral responses, despite protective immune responses in the dam.

Conclusion  Fetal PI with BVDV alters maternal immune function, compromises fetal growth and immune responses, and results in expression of maternal blood biomarkers that can be used to identify cows carrying PI fetuses.
Pathogenesis of tinea
Authors: Brasch Jochen
Published: July 2010

Dermatophytes are hyphomycetes that can degrade keratin. This puts them in a position to cause infections of the keratin‐containing superficial skin. The resulting clinical picture is called tinea. The pathogenesis and course of tinea is decisively determined by pathogen‐related factors and by the defense mechanisms of the host. An infection starts with an adherence of fungal propagules, followed by the formation of hyphae that can spread within the tissue. This process is accompanied by a release of fungal enzymes and other pathogenic factors. Next keratinocytes are activated, the epidermal barrier is destroyed, epidermal proliferation is enhanced and defensins are expressed within the epidermis. In addition, innate and specific immune responses are initiated, involving neutrophilic granulocytes, macrophages, antibodies and T cells. The cellular mechanisms are thought to be crucial for healing. Special conditions apply to nail infections, because within nail plates the fungi are not accessible to effective defense mechanisms, as well as to infections of hair follicles that contain specific concentrations of steroid hormones. Dermatophytes that penetrate into the dermis can cause granulomatous inflammatory reactions and systemic immune reactions are supposed to be a trigger of so‐called id reactions.
THE ANTIBACTERICIDAL EFFECT OF RABBIT ANTISERUM ON THE KILLING OF A SMOOTH STRAIN OF SALMONELLA ENTERITIDIS BY CATTLE NORMAL SERUM
Authors: Normann Bengt , Schenström Ola , Edebo Lars
Published: July 2010

Rabbit serum, that is hyperimmune to a smooth, virulent strain of Salmonella enteritidis inhibits the bactericidal effect of normal cattle serum on the strain. After fractionation on DEAE‐cellulose such activity was demonstrated in the IgG‐antibody fraction. If further purified on Sephadex G‐25 and tested in immunoelectrophoresis with anti‐whole rabbit serum, the antibactericidal fraction, gave a single precipitation arc, identical with the line developed with specific anti‐rabbit IgG serum.
AN IMMUNOFLUORESCENCE STUDY ON THE HUMORAL IMMUNITY TO STREP. 2A IN RECURRENT APHTHOUS STOMATITIS
Authors: Donatsky O. , Dabelsteen E.
Published: July 2010

The occurrence of humoral antibodies to Strep. 2A in recurrent aphthous stomatitis (RAS) was investigated by titrating sera and by using a double‐layer immunofluorescence staining method. The series comprised 24 patients with RAS and 24 persons without anamnestic or clinical signs of RAS. The distribution of endpoint titre in RAS differed significantly in relation to the distribution in the controls (p<0.005). No antibodies to a strain of Streptomyces and a strain of Neisseria used were demonstrated in RAS. The results indicate that Strep. 2A hypersensitivity is a feature of RAS.
Imperfect competition, technical progress and capital accumulation
Authors: D'Onofrio Biancamaria , Wigniolle Bertrand
Published: July 2010

This paper constructs a dynamic equilibrium growth model, in which some firms act as monopsonies on the labor market. The framework is an overlapping generations growth model with altruistic agents. Two types of firms exist, competitive and non‐competitive, the latter being endowed with a more productive technology. They behave strategically on the labor market, in taking into account the impact of their demand for labor on the equilibrium wage and on their profit. In this framework, the impact of technical progress on capital accumulation can be positive or negative, depending on its effect on monopsony power.
Analysis of the morphological attributes of a sweetpotato collection
Authors: Manifesto M.M. , Costa Tártara S.M. , Arizio C.M. , Alvarez M.A. , Hompanera N.R.
Published: July 2010

The knowledge about the distribution of descriptors of a collection constitutes a useful tool for the management of genetic resources. The object of this work was to evaluate the composition and morphological characterisation of the ‘in vitro’ collection kept at the Gene Bank of the Biological Resources Institute (IRB), INTA Castelar, Argentina, to establish conservation criteria and make available useful data for breeding programmes. This collection, comprising 310 sweetpotato clones, includes landraces, worldwide clones, commercial varieties and breeding material. The descriptors, which presented the highest correlation values, were leaf lobe types, the shape of central leaf lobes and general leaf outline. Cluster analyses showed eight major groups with an average similarity of 0.42 (SE ± 0.005). About 76% of the clones presented unique morphology, whereas 34% of them were distributed in 22 groups that could not be distinguished with this technique. Worldwide germplasm formed a separate group with values of diversity higher than those of the Argentinean clones and no duplicates. A projection of the phenotypic variation among cultivars was obtained through Principal Coordinate Analysis (PCoorA), which confirmed the results obtained by UPGMA analysis, predominant skin colour, secondary skin colour, number of leaf lobes, general leaf outline, petiole pigmentation and predominant colour of vine were the variables that made the highest contribution. Collection composition in reference to flesh and skin colour was also analysed.
Work and financial stability in late‐onset first‐episode psychosis
Authors: Woodside Harriet , Krupa Terry
Published: July 2010

Aim: To explore employment and financial experiences of persons with late‐onset first‐episode (LOFE) psychosis.

Methods: The study used a grounded theory approach. The subjects were eight participants and five secondary participants from a larger study. Data in the form of interview texts were coded. Analysis focused on work and financial considerations before treatment of psychosis and during recovery.

Results: In LOFE participants, their illness disrupted an established work history. Their recovery goals focused on returning to work and were driven by financial need.

Conclusions: It is important for clinicians to consider return to work and financial issues when supporting the recovery of individuals with late‐onset first‐episode psychosis. Examples of interventions include counseling about financial benefits, negotiating workplace accommodations and identifying new workplace skills. The study suggests the importance of connecting with employers during early detection campaigns.
An Outsider in My Own Home: Attachment Injury in Stepcouple Relationships
Authors: Sayre Julia B. , McCollum Eric E. , Spring Elizabeth L.
Published: July 2010

This multiple‐case study explored women’s relational experiences as attachment injury patterns in distressed stepcouple relationships and how these experiences might be attributable to stepcouple status. The first author interviewed five stepmothers with biological children, using open‐ended interview questions developed from attachment theory and existing research regarding attachment injury and stepfamily formation. Data analysis using the pattern‐matching method derived and explored markers of attachment injury in the women’s stepcouple relationships. The four categories of attachment injury showed significant attribution to stepfamily issues. This supports past stepfamily research suggesting that stepcouples face unique challenges. Further, these findings suggest that the language of attachment injury accurately describes stepcouples’ problems and the usefulness of conceptualizing and addressing these problems in an attachment injury framework.
Can Sanctions Reduce Insider Trading? The Experience of the USA in the 1980s
Authors: Min Se‐Jin
Published: July 2010

This paper empirically examines whether insider trading sanctions in the USA in the 1980s reduced insider trading in advance of mergers and acquisitions (M&A). Using a sample consisting of 291 firms, both merged and non‐merged in 1983 and 1989, I measured insider trading volume and the “news media effect.” I conclude that the sanctions reduced insider trading on average, and also resulted in larger noise trading on M&A‐related news and rumors. No evidence was found that insiders were increasingly camouflaging their trades by concentrating them on days on that they knew trading volume would be abnormally high, such as on days containing M&A‐related news.
Off-Road Tire-Soil Modeling Using Finite Element Analysis Technique
Authors: Slade Jeff , El-Gindy Moustafa , Lescoe Ryan , O¨ijer Fredrik , Trivedi Mukesh , Johansson Inge
Published: July 2010

A new rigid ring model with additional parameters was developed to model an off-road tire running on soil. In order to create this new rigid ring model, an FEA off-road truck tire was created and used to determine the in-plane and out-of-plane parameters for a tire running on soil. The soil, dense sand in this case, was modeled as an elastic-plastic solid with material properties obtained from published data. The longitudinal forces and the normal stress and shear stress distributions in the soil are compared with published data as preliminary validation. The general trends of soil flow from a rigid wheel model running on soil were used to validate the soil model. In addition, a model of a standard circular plate was used to determine the vertical pressure-sinkage curves and then these simulations were compared with available published measured data.
Pattern Design of Non-Pneumatic Tire for Stiffness Using Topology Optimization
Authors: Kwak Byung Man , Yoo Eui Jong , Sung Young Hwa , Jang In Gwun
Published: July 2010

Non-pneumatic tires have been developed and being investigated, but not much prevalent. Many design studies are yet needed from the viewpoint of material, pattern, and structures. No systematic research for such important design issues have been reported in the literature. In this paper, as the first important step of design, topology optimization was utilized to determine optimal topological patterns of non-pneumatic tires, with the goal of matching the static stiffness of the current pneumatic tires. Under the optimization formulation with weighted compliance and a volume constraint, several different patterns were obtained depending on the number of patterns, volume fraction, and weighting factors. Among them, three representative patterns were chosen and analyzed for their possible applications under specific working condition. This paper proposes a systematic and efficient tool for designing the topological patterns of non-pneumatic tires.
Case Study in Systematic Design Engineering: Smoke Gas Dust Precipitation
Authors: Eder W. Ernst
Published: July 2010

Students learning design engineering at times need a good example of procedure for novel design engineering. The systematic heuristic-strategic use of a theory to guide the design process — Engineering Design Science — and methodical design process followed in this case study is only necessary in limited situations. The full procedure should be learned, such that the student can select appropriate parts for other applications. Creativity is usually characterized by a wide search for solutions, especially those that are innovative. The search can be helped by this systematic and methodical approach. This case example is presented to show application of the recommended method, and the expected scope of the output, with emphasis on the stages of conceptualizing. The case follows a novel design problem of a smoke gas dust precipitation process and the necessary technical system, including a sub-problem of a rapper for dust removal.
Computer-Aided Edge Loop Theory of Kinematic Structure of Mechanisms and Its Applications
Authors: Ding Huafeng , Zhao Jing , Li Qinchuan , Huang Zhen
Published: July 2010

Based on the edge-based array representation of loops in the topological graphs of kinematic chains, this paper first proposes three arithmetic operations of loops. Then the concept of the independent loop set as well as it determination rules is introduced, and a new structure decomposition algorithm of kinematic chains is presented. Based on the algorithm, an automatic and efficient method for rigid subchain detection and driving pair selection of kinematic chains is proposed. Finally, an index is proposed to assess computation complexity of kinematic analysis with respect to different driving pair selections.
A 3-DOF Translational Compliant Parallel Manipulator Based on Flexure Motion
Authors: Hao Guangbo , Kong Xianwen
Published: July 2010

This paper presents a novel class of 3-DOF translational compliant parallel manipulators (CPMs) based on flexure motion. The analytic mathematic modeling of CPMs is first developed. The analysis of CPMs is then implemented. It is shown that the proposed CPMs have many characteristics such as large range of motion, negligible cross-axis coupling, actuator complete isolation, and no loss motion and no rotational yaw. The inverse relationships of force-displacement of the 3-DOF CPM are further derived to calculate the input forces required for generating a specified path. In addition, the 3-DOF CPM can also be turned into a 2-DOF CPM. This work lays the foundation for the development of new spatial CPMs based on flexure motions for applications such as ultra precision manipulation.
Liftable Auxiliary Axle for a Multi Axle Vehicle: A Review
Authors: Grinspon A. Sahaya
Published: July 2010

Retractable suspension system is used to lift the auxiliary axle of a multi axle vehicle. The article summarizes the current state of knowledge of the lifting mechanisms, which are used for lifting and lowering the auxiliary axle. Various designs of liftable axle are described. To proper use of the auxiliary axle, important guidelines are given for suppliers, OEMs and customers. Several viable steerable and non-steerable liftable axles are developed with various load carrying capacities using air bellows. In these liftable axles, the air bellows expands when compressed air is supplied to the air bellows at a required pressure. The air bellows activates the lifting mechanism; thereby the tires of the auxiliary axle are lifted from the road surface. When the air is released from the air bellows, the tires are lowered to engage the road surface.
Fuel Efficiency Strategic Plan of Medium-Duty Tactical Truck
Authors: Quail Allen M. , Liao Y. Gene , Gonzalez Rodrigo , O’Malley Molly , Duong Tai H. , Skalny Paul F.
Published: July 2010

This paper reports the planning efforts on reducing fuel consumption rate in the current fleet of medium-duty tactical truck. A strategic plan was developed through investigation of current and future technology offerings from original equipment manufacturers and aftermarket suppliers. Research efforts consisted of an initial phase where a broad range of integration candidates were collected and a secondary phase where in-depth analysis was conducted to target those to consider for inclusion in the strategic plan. Each product was evaluated on its technical merits with consideration given to the needs and strategic goals of government agencies. The strategic plan lays out the integrated technologies in the near-term including hydrogen injection and auxiliary electrification of engine cooling fan. For the mid-term timeframe, the plan involves implementing an engine stop/start system and electrifying other auxiliaries. The final step in the plan is the development and implementation of a full (strong) hybrid population.
Comparison Study on Three Approaches for Type Synthesis of Robot Mechanisms
Authors: Yang Ting-Li , Liu An-xin , Luo Yu-Feng , Zhang Li-Ping , Shen Hui-Ping , Hang Lu-Bin
Published: July 2010

Basic principles and main characteristics of three approaches for structure synthesis of robot mechanisms (the screw theory-based approach, the displacement subgroup-based approach and the approach based on position and orientation characteristic (in short, POC) ) are studied and compared in this paper. The comparison deals with the mathematical tools, the symbolic representation of mechanism topological structure, the mathematical representation of POC of the output motion link with respect to the frame link, the basic equations for structure synthesis of serial and parallel mechanisms and relevant operation rules, and the characteristics of their synthesized mechanisms, etc. This comparative study shows that the POC-based approach is totally different from the other two approaches: (1) the POC-based approach requires only simple mathematical tools (such as vector algebra, set theory, etc), (2) the POC-based approach is conceptually simpler and therefore easier to understand and to use, and (3) the POC-based approach is more general.
Joint Pricing and Platform Configuration in Product Family Design With Genetic Algorithm
Authors: Qian Li , Ben-Arieh David
Published: July 2010

Manufacturers add numerous product variants to address different customer preferences for mass customization. One approach to implement the mass customization is to develop or produce products based on the platform architecture. A platform is a set of common components, modules or parts shared by product variants in one product family. One product variant makes use of the platform as the starting point and then add or remove components to change features of the product. The problem of determining the platform configuration is considered as maximizing the overall profit under the price-dependent demand market environment while satisfying the part assembly constraints. Platform configuration and sale prices are decision variables in the problem. A strategy based on Genetic Algorithm is proposed to solve the illustrating problem involving the product family of cordless drills. Results manifest that the sale price decision could have significant influence on the product family design, e.g. the platform configuration and the profitability of one product family.
Modelling, Sensitivity Analysis and Optimization of Mechanisms Made of Micro-Molded Components
Authors: Albers Albert , Leslabay Pablo E.
Published: July 2010

The miniaturization of metallic and ceramic molded components is limited by technological restrictions in conventional manufacturing techniques. Thus shape and material deviations cannot be scaled down in the same proportion as the micro parts. Systems including such components should be designed to accommodate the individual component’s wide geometrical variation and usually require large clearance. A study of the effects introduced thereby is needed to understand the system’s limits and to be able to forecast their output’s performance. To save time and resources, costly prototypes and test runs should be avoided in favour of computer simulation. The method proposed by the authors is exemplified on a micro technology demonstrator system developed by the Collaborative Research Center 499. It consists of a one stage planetary gear train in a sun-planet-ring configuration. The simulation procedure relies on ordinary Multi Body Simulation methods and subsequently adds other techniques to further investigate details of the system’s behaviour and to predict it’s response. In order to quantify the variability and to reveal the most critical points of the system, a whole-mechanism Sensitivity Analysis is performed. A reduced set of relevant parameters could be derived for further investigation and to feed a final optimization process, whether as optimization parameters or as external perturbation collective. The lack of previous knowledge about the system forced different DOE methods, involving small and large amount of experiments, to be tested. In this particular case the parameter space can be divided into two well defined groups, one of them containing the gear’s profile information and the other the components’ spatial location. This has been exploited to explore the different DOE techniques more promptly. Comparison and an analysis of the most successful DOE methods is included. In a final optimization step, the 10 most relevant perturbation factors and 4 to 6 prospective target parameters are included in a new, simplified model. All of these, and the objective functions, are affected by the production variability and the problem becomes an optimization of the system’s robustness and reliability exercise. Different techniques are discussed with examples. The study shows a first step in the development path of methods for designing and optimizing complex micro mechanisms composed of wide tolerated elements, accounting for the robustness and reliability of the systems’ output.
Solving Inverse Kinematics and Driving Forces of a Novel 3RPS-3SPR Serial-Parallel Manipulator
Authors: Hu Bo , Lu Yi , Xu Jia Yin , Yu Jing Jing
Published: July 2010

The inverse kinematics and the driving forces of a 3RPS-3SPR serial-parallel manipulator (PM) with 6 degree of freedoms (DOFs) are solved in this paper. This 3RPS-3SPR serial-PM includes a lower 3-RPS PM and an upper 3-SPR PM. First, the inverse displacement is solved based on the geometrical constraint and the dimension constraint of this PM. Second, the 9×9 and 6×6 form inverse Jacobian matrices are derived and the driving forces are solved by using principle of virtual work. Finally, the numerical example is given.
A Kind of Kinematically Redundant Planar Parallel Manipulator for Optimal Output Accuracy
Authors: Chen Genliang , Wang Hao , Zhao Yong , Lin Zhongqin
Published: July 2010

Theoretically, parallel manipulators perform higher precision than their serial counterparts. However, the output accuracy is sensitive to their configurations and dimensions. This paper presents a kind of parallel manipulator with kinematically redundant structure, which can improve the output accuracy by optimizing the error transmission from the active joints to the end-effector. With the kinematic redundancy, free redundant variables can be defined as second task variables, which provide the possibility to select a proper configuration for least error transmission at any pose (the position and orientation) of the end-effector for a given task. Contrast to non-redundant manipulators, the output errors of the proposed manipulator, caused by the active joints input errors, can be optimized rather than determined. By this goal, new limbs with redundant parallel structures are introduced to non-redundant planar parallel manipulators. Numerical example shows that the new architecture has the potential to enhance the output accuracy for a given pose or prescribed trajectory of the end-effector.
Self Motions of the Pantopteron
Authors: Briot Se´bastien , Bonev Ilian A.
Published: July 2010

In this paper, the self motions of a novel 3-DOF fully decoupled translational parallel robot, called the Pantopteron, are presented. The Pantopteron is similar to the well-known Cartesian parallel manipulator (Tripteron), but due to the use of pantograph linkages, an amplification effect is achieved. Therefore, equipped with the same actuators, the mobile platform of the Pantopteron moves faster than that of the Tripteron. This amplification is defined by the magnification factor of the pantograph linkages. The self motions are probably the most critical types of singularities a manipulator can meet. Therefore it is of utmost importance to have a good knowledge of them. Design considerations are also discussed in order to create Pantopterons without self motions.
On the Optimal Design of Parallel Robots Taking Into Account Their Deformations and Natural Frequencies
Authors: Briot Se´bastien , Pashkevich Anatol , Chablat Damien
Published: July 2010

This paper discusses the utility of using simple stiffness and vibrations models, based on the Jacobian matrix of a manipulator and only the rigidity of the actuators, whenever its geometry is optimised. In many works, these simplified models are used to propose optimal design of robots. However, the elasticity of the drive system is often negligible in comparison with the elasticity of the elements, especially in applications where high dynamic performances are needed. Therefore, the use of such a simplified model may lead to the creation of robots with long legs, which will be submitted to large bending and twisting deformations. This paper presents an example of manipulator for which it is preferable to use a complete stiffness or vibration model to obtain the most suitable design and shows that the use of simplified models can lead to mechanisms with poorer rigidity.
A New Approach for the Orders of the Bennett-Based Linkages in Mobility Analysis
Authors: Liu Jingfang , Huang Zhen , Li Yanwen
Published: July 2010

Among the 3D single-loop overconstrained linkages, quite a number of them are combinations of Bennett linkages. Mobility on the overconstrained linkages including the Bennett-based linkages is known to be one of the difficult topics in kinematics. In the paper, a new approach based on the linear superposition principle for determining the orders of Bennett-based linkages is proposed, and the mobility of some typical Bennett-based linkages is calculated with the Modified Gru¨bler-Kutzbach criterion. In addition, geometric properties of some of the screw systems are employed to identify whether the mobility is global.
Hertzian Contact Pressure Analysis of Frictional Coupling Elements of Multidisk Stepless Transmission With Initial Line Contact
Authors: Lukowski S. A. , Medeksza L. A. , Kunz D. N. , Hoerning Jeff
Published: July 2010

This paper presents an analysis of the contact pressures and the contact area of mating disks in a frictional transmission. Hertz’s formulations are adopted to determine the maximum contact pressures as well as the size of the contact area resulting from elastic deformation due to the clamping force. Hertz’s formulations are expressed in terms of geometrical features of the active surface of mating disks. The obtained relationships can be readily applied for quantitative estimation of the contact pressures and the contact area parameters for different ranges of transmission ratio. Samples of numerical results are presented in graphical form.
Optimized Mask Image Projection for Solid Freeform Fabrication
Authors: Zhou Chi , Chen Yong , Waltz Richard A.
Published: July 2010

Solid freeform fabrication (SFF) processes based on mask image projection have the potential to be fast and inexpensive. More and more research and commercial systems have been developed based on these processes. For the SFF processes, the mask image planning is an important process planning step. In this paper, we present an optimization based method for mask image planning. It is based on a light intensity blending technique called pixel blending. By intelligently controlling pixels’ gray scale values, the SFF processes can achieve a much higher XY resolution and accordingly better part quality. We mathematically define the pixel blending problem and discuss its properties. Based on the formulation, we present several optimization models for solving the problem including a mixed integer programming model, a linear programming model, and a two-stage optimization model. Both simulated and physical experiments for various CAD models are presented to demonstrate the effectiveness and efficiency of our method.
Workspace Investigation of a Novel Parallel Manipulator
Authors: Li Yanwen , Xi Fengfeng , Wang Lumin , Zhang Yueyue , Huang Zhen
Published: July 2010

The manipulator workspace denotes the work area of a manipulator and it is an important foundation of designing a robot. The workspace of a novel symmetrical 4-DOF 3-RRUR parallel manipulator is researched here based on the inverse solution. Five essential conditions of a point within the workspace of the manipulator are presented and the cause of the existence of each condition is given. According to the characteristics of this parallel mechanism and the geometrics, and based on the inverse kinematical solution of the mechanism, the reachable workspace under the five conditions is ascertained. The three-dimensional graph and its section graphs of the workspace are obtained. The thoroughness of the workspace of the manipulator is proved. The mechanism with the advantages of simple symmetric structure and large stiffness can be applied to the developments of four-dimensional force sensors, NC positioning platforms, parallel machine tools and micro-positional parallel manipulators. This work is with great significance to the practical application of the manipulator.
Self-Locking of 2S-C Type Planetary Gear Train Composed of External Gears
Authors: Ikejo Kiyotaka , Nagamura Kazuteru , Yada Tuneji , Kagari Yoshiya
Published: July 2010

A planetary gear train is used in a transmission in many fields, because it has a smaller size, a lighter weight, and a larger gear ratio than a conventional gear train. However, a planetary gear train has a lower efficiency than a conventional gear train. Self-locking sometimes occurs, in which case the planetary gear train can not be driven, because of a significant low efficiency. In this study, we theoretically analyzed the efficiency of a 2S-C type planetary gear train composed of external gears, and presented the condition in which the self-locking occurs. Furthermore, we examined the self-locking of 2S-C type planetary gear train composed of external gears using several gear sets with different numbers of teeth by the practical test. As the result, the condition of the self-locking which was analyzed theoretically agreed with experimental result.
Biological Inspired Flying Robot
Authors: Couceiro Micael S. , Figueiredo Carlos M. , Ferreira N. M. Fonseca , Machado J. A. Tenreiro
Published: July 2010

This paper presents the development of computational simulation based on the dynamics of a robotic bird. The study analyze the wing angle of attack and the velocity of the bird, the tail influence, the gliding flight and the flapping flight with different strategies and algorithms of control. The results are positive for the construction of flying robots. Some highlights are given about the fist implemented architecture of the structure of a robotic bird. This platform consists on a body, wings and tail with actuators independently controlled though a microcontroller; a radio transmission system and batteries are used in order to avoid wired connections between the computer and the robot.
Multidisciplinary Master Design Projects Based on Workshops for Professionals
Authors: Zeiler Wim , Savanovic Perica , van Houten Rinus
Published: July 2010

The growing complexity in (Dutch) building practice necessitates developments in other aspects, besides specialized and professional skills. Therefore a new integral approach in building design education has been developed in close cooperation with building design practice. In 2005, the building services chair of the Faculty of Architecture, Building and Planning of the TU/e commenced a multidisciplinary master project ‘Integral Design’ focused on a sustainable climatic design. In this and the following Multidisciplinary Master projects students of architecture, building technology, structural engineering and building services participated. The students began with a two days learning-by-practice workshop which was implemented and tested in collaboration with experienced professionals from the Royal Institute of Dutch Architects (BNA) and the Dutch Association of Consulting Engineers (ONRI). This is one of the few projects in which the practical experience is transferred into the educational academic program; normally this process functions the other way around. The theoretical basis of the combined education of students and professionals is discussed and results presented. Quite remarkable is that these workshops by themselves have become part of the permanent professional educational program of the BNA.
Utilizing an A3 Report Format for a Technical Review at the End of a Cornerstone Design Course
Authors: Leipold Kate , Landschoot Timothy
Published: July 2010

The goal of this paper is to demonstrate the advantages of implementing an alternative technical review technique in an engineering design course. Historically formal design reviews associated with the Cornerstone Design course have utilized a Power Point type of presentation for evaluation of a design project status. A case study will be presented involving the use of a project summary report for a comprehensive design project review based on a Toyota management communication tool known as the “A3 Report”. The objectives for utilizing the this report format as an alternative to the presentation format were to require project team members to integrate their individual sub-system designs into their final system proposal, identify the critical aspects of their design, and prepare for detailed questions regarding their design. Conclusions and recommendations from the perspective of both the instructors and the students will be presented, including points of concern with the implementation.
A Computer Aided Engineering Approach for the Optimal Design of an Active Suspension System
Authors: Gubitosa Marco , Anthonis Jan , Albarello Nicolas , Desmet Wim
Published: July 2010

Within companies dealing with the automotive market, and in particular for product designers, the usage of numerical simulations is a well established technique to help achieving faster development cycles. Focusing on the very first phase of the design development chain conceptual (ID) modeling software is better suited. Furthermore considering the multiphysics nature of vehicle subsystems, a multidisciplinary system modeling tool is required, which has to be enriched with optimization capabilities in order to produce a suitable design of complex systems involving multiphysics functionalities (for instance for active safety and energy management). The purpose of this paper is to summarize a procedure that has been applied for the optimal design of an active suspension with hydraulic actuation, governed by a general control strategy based on the sky-hook approach, to be manufactured by Tenneco. A 15 Degrees of Freedom (DOF) vehicle model, built in a commercially available 1D simulation environment, has been validated as a first step towards achieving a good correlation with experimental results obtained on the test tracks. As a next step, the sky-hook based control strategy was implemented to take into account the active behavior of the system, and to define the load profiles acting on the suspension dampers while the vehicle is virtually tested on ride roads. Optimization loops were performed in a nested architecture in order to define the optimal gains needed to meet certain performance requirements dictated by the vehicle manufacturer. A detailed model of the damping system was implemented in LMS Imagine.Lab AMESim capturing its multidisciplinary nature including mechanical, hydraulic and electrical aspects. The mission profiles (force-velocity couples at the dampers) were used as input to the simulations to investigate the damping system design parameters considering performance achievement and energy efficiency goals. The results of this project have been used by Tenneco as guidelines for the physical prototype implementation of the active suspension system.
Wireless Modular Control Hardware Architecture for Hybrid Mechanism Mobile Robot
Authors: Ben-Tzvi Pinhas
Published: July 2010

This paper presents a new generalized control hardware architecture based on embedded on-board wireless communication network between robot’s links and modules such as the actuators and sensors. This approach results in modular control hardware architecture since no cable connections are used between the actuators and sensors in each of a given mobile robot subsystems (links). The effectiveness of this approach is experimentally demonstrated and validated by implementing it with a hybrid mobile robot mechanism as a case study. The hybrid mobile robot mechanism integrates the locomotion mechanism and manipulator arm mechanism as one entity to support both locomotion and manipulation simultaneously and interchangeably.
Crowning Techniques in Aerospace Actuation Gearing
Authors: Wang Anngwo , El-Bayoumy Lotfi
Published: July 2010

One of the most important methods to solve the edge loading problem due to excess misalignment and deflection in aerospace actuation gearing is to localize tooth bearing contact by crowning the teeth. Irrespective of the applied load, if the misalignment and/or deflection are large enough to cause the contact area to reduce to zero, the stress becomes large enough to cause damage. The edge loading could cause the teeth to break or pit, but too much crowning may also cause the teeth to pit due to concentrated loading. In this paper, a proposed method to localize the contact bearing area and calculate the contact stress with crowning is presented and demonstrated on some real life examples in aerospace actuation systems.
Design Parameter Investigation in Customer-Oriented Drive Train Development Using Human Sensation Modeling Tools
Authors: Albers Albert , Lerspalungsanti Sarawut , Du¨ser Tobias , Ott Sascha
Published: July 2010

The integration of customer demands in the early phase of product development process is one of most important aspects in the field of automotive engineering. In addition to a customer survey which generally requires drive tests of the real prototypes, methods based on the virtual product design have been applied more and more frequently. Due to the potential of simulation methods, the development time can be shortened and the costly prototypes as well as the time-consuming drive tests can be partially excluded. Earlier studies have demonstrated a capability of the developed methods and tools to support the customer-oriented drive train design by means of the prediction of the subjective comfort evaluation. In this case, the potential customers are classified into three groups based on their comfort expectation and style of driving. The rating from the customer point of view is accordingly achieved by modeling of the human sensation from the way the individual passengers make their evaluation by means of the Artificial Neural Networks (ANN). The objective of the current research is to implement the developed methods in the design phase of the drive train development process to enhance the customer comfortability. This article presents a systematic approach to apply the simulation methods in order to investigate different design parameters of the drive train and to determine the consequent customer comfort evaluation during each driving situation, the vehicle start-up as an example. For this purpose, the modification of the elaborated vehicle model is carried out by variation of the comfort-relevant design parameters, such as the friction coefficient gradient of the clutch friction pair, the mass of inertia and the damping of the components, like the dual mass flywheel. Depending on each drive train configuration and driver demand on the vehicle start-up, the simulated driving situation with different effects on the occurrence of the rotary vibration is evaluated by means of the human sensation model. This is developed during the drive tests on the basis of driver rating behavior. Based on the predicted comfort evaluations from different types of customer, the decisions made by the developer such as the determination of the clutch disk property or the damping setting of component can be efficiently supported during the drive train design. Hence, a new drive train concept can be tested and improved in such a way that the satisfaction of a target customer group from the first prototypes is obtained.
A Framework for Considering Uncertainty in Quantitative Life Cycle Cost Estimation
Authors: Goh Yee Mey , Newnes Linda , McMahon Chris , Mileham Antony , Paredis Christiaan J. J.
Published: July 2010

Life Cycle Cost (LCC) is important information that is useful for decision making affecting complex engineering systems with extended life. Uncertainty in the estimation of LCC, especially in the early concept and definition stage, has great influence on the robustness of such decisions. Conventionally, Verification and Validation (V&V) of cost estimates is not performed, either due to economic or practical constraints. This paper presents a framework for considering uncertainties in quantitative life cycle cost estimation, focusing on the aspects that are important for understanding the discrepancies between the estimated and actual costs. Built on experience in verification and validation in engineering, the framework will be used to guide further research in this topic, where emphasis on suitable theories and models of different types of uncertainties in the estimation as well as strategies to deal with them effectively to improve decision making involving LCC will be discussed.