Liquid phase IR-MALDI and differential mobility analysis of nano- and sub-micron particles

Infrared matrix-assisted desorption and ionization (IR-MALDI) enables the transfer of sub-micron particles (sMP) directly from suspensions into the gas phase and their characterization with differential mobility (DM) analysis.

Dynamic Modelling of Piston the Motion in Combustion Engines

The presented work discusses a methodology for analysis of noise emissions from a diesel engine. A numerical model of the piston motion, analyzing its lateral, reciprocating and rotation motion, has been presented in order to investigate the lateral motion of the piston skirt assembly and resulting vibrations induced as a result of these motions in the engine block. Various parameters of modal analysis were obtained using the mobility analysis. The presented methodology was validated by data obtained from a diesel engine test set up. The predicted results matched well with those of measured data, hence validating the presented scheme.

Mobility Analysis of Persons with Disabilities

This study presents the results of the research on travel behaviour for persons with different types of disabilities. Persons with disabilities are a group of participants with specific traffic requirements often not included in traffic research and consequently adequate planning of urban transport. To obtain the data, a home interview was conducted on a representative sample. The paper presents the main results of the research and indicates the specificity of the requirements of this group of users. The results are compared with the results of the same research conducted for the development of the Smart Plan of Novi Sad and the results of similar research abroad. The main goal is to obtain a qualitative and quantitative database of the requirements of this group of users as a basis for creating sustainable urban mobility plans.

A Novel Mobile Device-Based Approach to Quantitative Mobility Measurements for Power Wheelchair Users

This study is motivated by the fact that there are currently no widely used applications available to quantitatively measure a power wheelchair user’s mobility, which is an important indicator of quality of life. To address this issue, we propose an approach that allows power wheelchair users to use their own mobile devices, e.g., a smartphone or smartwatch, to non-intrusively collect mobility data in their daily life. However, the convenience of data collection brings substantial challenges in data analysis because the data patterns associated with wheelchair maneuvers are not as strong as other activities, e.g., walking, running, etc. In addition, the built-in sensors in different mobile devices create significant heterogeneity in terms of sensitivity, noise patterns, sampling settings, etc. To address the aforementioned challenges, we developed a novel approach composed of algorithms that work collaboratively to reduce noise, identify patterns intrinsic to wheelchair maneuvers, and finalize mobility analysis by removing spikes and dips caused by abrupt maneuver changes. We conducted a series of experiments to evaluate the proposed approach. Experimental results showed that our approach could accurately determine wheelchair maneuvers regardless of the models and placements of the mobile devices.

In Praise of Snapshots

The conventional justification for moving from income distribution to intergenerational mobility analysis is that the movie encompasses the snapshot and is normatively superior as the basis for assessing policy. Such a perspective underpins many an argument for shifting the focus from income redistribution, which is said to equalize outcomes, to equalizing opportunity by increasing mobility through education policy such as equal provision of public education. This chapter argues that this perspective can be misleading. It shows that normative evaluation of income mobility in any event often falls back on a snapshot perspective. Further, the snapshot itself often contains the seeds of the movie, as posited in the Great Gatsby Curve. Income redistribution can itself improve mobility even if that is the only objective. The chapter thus speaks in praise of snapshots.

Enumeration and instantaneous mobility analysis of a class of 3-UPU parallel manipulators with equilateral triangular platforms

In this study, several joint axis orientations on equilateral platforms and the limbs of 3-UPU parallel manipulators (PMs) are examined. The generated joint layouts for the platforms were matched with each other to generate and enumerate manipulator architectures based on certain assumptions. The structures of thus obtained manipulators are examined and limb types were determined. These limb types were analyzed using screw theory. The instantaneous mobility of the manipulators and the motion characteristics of the moving platforms are tabulated. The finite mobility analysis of one of the manipulators is performed using a software package as an example. Among several different 3-UPU PM architectures, 118 novel 3-UPU PMs with non-parasitic 3-degrees-of-freedom are significantly important. The classified 3-UPU PMs with determined motion characteristics can be used by researchers as a design alternative for their specific design task.

Virtual and Physical Prototyping of Reconfigurable Parallel Mechanisms with Single Actuation

The paper presents novel models of reconfigurable parallel mechanisms (RPMs) with a single active degree-of-freedom (1-DOF). The mechanisms contain three to six identical kinematic chains, which provide three (for the tripod) to zero (for the hexapod) uncontrollable DOFs. Screw theory is applied to carry out mobility analysis and proves the existence of controllable and uncontrollable DOFs of these mechanisms. Each kinematic chain in the synthesized mechanisms consists of planar and spatial parts. Such a design provides them with reconfiguration capabilities even when the driving link is fixed. This allows reproduction of diverse output trajectories without using additional actuators. In this paper, the model of a mechanism with six kinematic chains (hexapod) has been virtually and physically prototyped. The designing and assembling algorithms are developed using the detailed computer-aided design (CAD) model, which was further used to carry out kinetostatic analysis considering complex geometry of mechanism elements and friction among all contacting surfaces of joints. The developed virtual prototype and its calculation data have been further applied to fabricate mechanism elements and assemble an actuated full-scale physical prototype for future testing.