Physical Setup Research Articles

MovExp: A Versatile Visualization Tool for Human-Computer Interaction Studies with 3D Performance and Biomechanical Data.

In Human-Computer Interaction (HCI), experts seek to evaluate and compare the performance and ergonomics of user interfaces. Recently, a novel cost-efficient method for estimating physical ergonomics and performance has been introduced to HCI. It is based on optical motion capture and biomechanical simulation. It provides a rich source for analyzing human movements summarized in a multidimensional data set. Existing visualization tools do not sufficiently support the HCI experts in analyzing this data. We identified two shortcomings. First, appropriate visual encodings are missing particularly for the biomechanical aspects of the data. Second, the physical setup of the user interface cannot be incorporated explicitly into existing tools. We present MovExp, a versatile visualization tool that supports the evaluation of user interfaces. In particular, it can be easily adapted by the HCI experts to include the physical setup that is being evaluated, and visualize the data on top of it. Furthermore, it provides a variety of visual encodings to communicate muscular loads, movement directions, and other specifics of HCI studies that employ motion capture and biomechanical simulation. In this design study, we follow a problem-driven research approach. Based on a formalization of the visualization needs and the data structure, we formulate technical requirements for the visualization tool and present novel solutions to the analysis needs of the HCI experts. We show the utility of our tool with four case studies from the daily work of our HCI experts.

Validation experiments for LBM simulations of electron beam melting

This paper validates three-dimensional (3D) simulation results of electron beam melting (EBM) processes by comparing experimental and numerical data. The physical setup is presented which is discretized by a 3D thermal lattice Boltzmann method (LBM). An experimental process window is used for the validation depending on the line energy injected into the metal powder bed and the scan velocity of the electron beam. In the process window, the EBM products are classified into the categories, porous, good and swelling, depending on the quality of the surface. The same parameter sets are used to generate a numerical process window. A comparison of numerical and experimental process windows shows a good agreement. This validates the EBM model and justifies simulations for future improvements of the EBM processes. In particular, numerical simulations can be used to explain future process window scenarios and find the best parameter set for a good surface quality and dense products.

Vibrotactile sensitivity threshold: nonlinear stochastic mechanotransduction model of the Pacinian Corpuscle.

Based on recent discoveries of stretch and voltage activated ion channels in the receptive area of the Pacinian Corpuscle (PC), this paper describes a two-stage mechanotransduction model of its near threshold Vibrotactile (VT) sensitivity valid over 10Hz to a few kHz. The model is based on the nonlinear and stochastic behavior of the ion channels represented as dependent charge sources loaded with membrane impedance. It simulates the neural response of the PC considering the morphological and statistical properties of the receptor potential and action potential with the help of an adaptive relaxation pulse frequency modulator. This model also simulates the plateaus and nonmonotonic saturation of spike rate characteristics. The stochastic simulation based on the addition of mechanical and neural noise describes that the VT Sensitivity Threshold (VTST) at higher frequencies is more noise dependent. Above 800Hz even a SNR = 150 improves the neurophysiological VTST more than 3dBμ. In that frequency range, an absence of the entrainment threshold and a lower sensitivity index near the absolute threshold make the upper bound of the psychophysical VTST more dependent on the experimental protocol and physical set-up. This model can be extended to simulate the neural response of a group of PCs.

Guidelines for establishing a telemental health program to provide evidence-based therapy for trauma-exposed children and families.

Although similar rates of traumatic experiences exist in both rural and urban settings, mental health resources available to those living in rural areas are often scarce. Limited resources pose a problem for children and families living in rural areas, and several barriers to service access and utilization exist including reduced anonymity, few "after hours" services, decreased availability of evidence-based treatments, few specialty clinics, and expenses associated with travel, taking time off work, and provision of childcare. As a solution, the authors discuss the utility, use, and set-up of a telemental health program within an existing community outreach program. Suggestions for establishing a telemental health clinic are presented along with guidelines for the delivery of trauma-focused, cognitive-behavioral therapy (TF-CBT) via telemental health videoconferencing technology. Specific guidelines discussed include (1) establishing and using community partnerships, (2) Memoranda of Understanding (MOU), (3) equipment setup and technological resources, (4) videoconferencing software, (5) physical setup, (6) clinic administration, (7) service reimbursement and start-up costs, (8) therapy delivery modifications, and (9) delivering culturally competent services to rural and remote areas.

Modified inelastic bouncing ball model for describing the dynamics of granular materials in a vibrated container

We show that at the onset of convection, the acceleration of a confined granular material is not necessarily equal to that of its vibrated container. Convection happens when the material is able to counter the downward gravitational pull and accelerates at a rate that is equal to the gravitational acceleration g. We modify the Inelastic Bouncing Ball Model and incorporate the transmissibility parameter Tr which measures the efficiency that the external force driving the container is transmitted to the material itself. For a specified Tr value, the material is represented by an inelastic bouncing ball with a time-of-flight T(Γ;Tr) where Γ=A0ω2/g, is the dimensionless container acceleration, and A0 and ω are the driving amplitude and angular frequency, respectively. For a given Γ-range, the T(Γ;Tr) curve provides the bifurcation diagram of the perturbed material and a family of bifurcation diagrams is generated for a set of Tr values. We illustrate that Tr is useful in rationalizing experimental results produced by confined granular materials that is subjected to a range of applied force magnitudes. For the same physical set-up, the force transmission efficiency from the container to the grains may not remain constant as the force strength is varied. The efficiency is also affected by the presence or absence of air in the vibrated container.

Kinetic isotope effect in CO2 degassing: Insight from clumped and oxygen isotopes in laboratory precipitation experiments

Laboratory precipitation experiments provide the basis for the common calibration of both the oxygen isotope and the clumped isotope thermometers. These focus on CaCO3 crystals that form deep in the bulk of the solution, often by the bubbling of N2(g) through a saturated Ca(HCO3)2 solution, following the classic experiments on McCrea (1950). Here we examine oxygen and clumped isotopes in CaCO3 that was precipitated at the surface of a solution that undergoes passive CO2 degassing. This CaCO3 is affected by enhanced disequilibrium that is associated with degassing, and has therefore higher δ18O and lower Δ47 values than those of the accepted thermometer calibrations. These offsets from the common thermometers calibrations increase with decreasing temperature for Δ47 but decrease with decreasing temperature for δ18O. The Δ47-δ18O co-variance is therefore strongly temperature dependent, in contrast to theoretical predictions. This suggests an influence of additional fractionation in fast growing minerals, between DIC and calcite, that affects δ18O and counteracts some of the degassing related enrichment. This effect seems not to influence Δ47. The physical setup of CaCO3 minerals growing at the solution surface is analogous to the degassing and precipitation processes that occur in stalagmites, such that these laboratory experiments may help shed light on the isotopic disequilibrium that is observed in speleothems.

Regional climate modeling on European scales: a joint standard evaluation of the EURO-CORDEX RCM ensemble

Abstract. EURO-CORDEX is an international climate downscaling initiative that aims to provide high-resolution climate scenarios for Europe. Here an evaluation of the ERA-Interim-driven EURO-CORDEX regional climate model (RCM) ensemble is presented. The study documents the performance of the individual models in representing the basic spatiotemporal patterns of the European climate for the period 1989–2008. Model evaluation focuses on near-surface air temperature and precipitation, and uses the E-OBS data set as observational reference. The ensemble consists of 17 simulations carried out by seven different models at grid resolutions of 12 km (nine experiments) and 50 km (eight experiments). Several performance metrics computed from monthly and seasonal mean values are used to assess model performance over eight subdomains of the European continent. Results are compared to those for the ERA40-driven ENSEMBLES simulations. The analysis confirms the ability of RCMs to capture the basic features of the European climate, including its variability in space and time. But it also identifies nonnegligible deficiencies of the simulations for selected metrics, regions and seasons. Seasonally and regionally averaged temperature biases are mostly smaller than 1.5 °C, while precipitation biases are typically located in the ±40% range. Some bias characteristics, such as a predominant cold and wet bias in most seasons and over most parts of Europe and a warm and dry summer bias over southern and southeastern Europe reflect common model biases. For seasonal mean quantities averaged over large European subdomains, no clear benefit of an increased spatial resolution (12 vs. 50 km) can be identified. The bias ranges of the EURO-CORDEX ensemble mostly correspond to those of the ENSEMBLES simulations, but some improvements in model performance can be identified (e.g., a less pronounced southern European warm summer bias). The temperature bias spread across different configurations of one individual model can be of a similar magnitude as the spread across different models, demonstrating a strong influence of the specific choices in physical parameterizations and experimental setup on model performance. Based on a number of simply reproducible metrics, the present study quantifies the currently achievable accuracy of RCMs used for regional climate simulations over Europe and provides a quality standard for future model developments.

A CFD-kinetic model for the flotation rate constant, Part II: Model validation

A Computational Fluid Dynamics (CFD) model was validated against published experimental data for the prediction of the flotation rate constant. An Eulerian–Eulerian framework was applied for modelling the multiphase flow inside a standard laboratory scale Rushton turbine flotation tank. The dispersed k–ε turbulence model simulated the turbulent effects inside the tank, while the collision, attachment and stability efficiencies were calculated using the local values of hydrodynamic parameters. Volume-weighted average flotation rate constants were simulated for chalcopyrite and galena and compared against published experimental data for the same physical setup. The results showed that both qualitatively and quantitatively the developed CFD-kinetic model can predict the flotation rate constants with an acceptable level of accuracy. Moreover, the validations of rate constants for the flotation of chalcopyrite and galena under various contact angles, agitation rates and gas flow rates confirmed the predictive capability of this numerical approach for further flotation modelling.

Indirect pushing based automated micromanipulation of biological cells using optical tweezers

In this paper, we introduce an indirect pushing based technique for automated micromanipulation of biological cells. In indirect pushing, an optically trapped glass bead pushes a freely diffusing intermediate bead that in turn pushes a freely diffusing target cell towards a desired goal. Some cells can undergo significant changes in their behaviors as a result of direct exposure to a laser beam. Indirect pushing eliminates this problem by minimizing the exposure of the cell to the laser beam. We report an automated feedback planning algorithm that combines three motion maneuvers, namely, push, align, and backup for micromanipulation of cells. We have developed a dynamics based simulation model of indirect pushing dynamics and also identified parameters of measurement noise using physical experiments. We present an optimization-based approach for automated tuning of planner parameters to enhance its robustness. Finally, we have tested the developed planner using our optical tweezers physical setup and carried out a detailed analysis of the experimental results. The developed approach can be utilized in biological experiments for studying collective cell migration by accurately arranging the cells in arrays without exposing them to a laser beam.

Reproducibility in patient-specific IMRT QA.

The purpose of this study was to determine the reproducibility of patient‐specific, intensity‐modulated radiation therapy (IMRT) quality assurance (QA) results in a clinical setting. Six clinical patient plans were delivered to a variety of devices and analyses, including 1) radiographic film; 2) ion chamber; 3) 2D diode array delivered and analyzed in three different configurations (AP delivery with field‐by‐field analysis, AP delivery with composite analysis, and planned gantry angle delivery); 4) helical diode array; and 5) in‐house‐designed multiple ion chamber phantom. The six clinical plans were selected from a range of treatment sites and were of various levels of complexity. Of note, three of the plans had failed at least preliminary evaluation with our in‐house IMRT QA; the other three plans had passed QA. These plans were delivered three times sequentially without changing the setup, and then delivered two more times after breaking down and rebuilding the setup between each. This allowed for an investigation of reproducibility (in terms of dose, dose difference or percent of pixels passing gamma) of both the delivery and the physical setup. This study showed that the variability introduced from the setup was generally higher than the variability from redelivering the plan. Radiographic film showed the poorest reproducibility of the dosimeters investigated. In conclusion, the various IMRT QA systems demonstrated varying abilities to reproduce QA results consistently. All dosimetric devices demonstrated a reproducibility (coefficient of variation) of less than 4% in their QA results for all plans, with an average reproducibility of less than 2%. This work provides some quantification for the variability that may be seen for IMRT QA dosimeters.PACS numbers: 87.55.Qr, 87.56.Fc

From the first nuclear power plant to fourth-generation nuclear power installations [on the 60th anniversary of the World’s First nuclear power plant

Successful commissioning in the 1954 of the World’s First nuclear power plant constructed at the Institute for Physics and Power Engineering (IPPE) in Obninsk signaled a turn from military programs to peaceful utilization of atomic energy. Up to the decommissioning of this plant, the AM reactor served as one of the main reactor bases on which neutron-physical investigations and investigations in solid state physics were carried out, fuel rods and electricity generating channels were tested, and isotope products were bred. The plant served as a center for training Soviet and foreign specialists on nuclear power plants, the personnel of the Lenin nuclear-powered icebreaker, and others. The IPPE development history is linked with the names of I.V. Kurchatov, A.I. Leipunskii, D.I. Blokhintsev, A.P. Aleksandrov, and E.P. Slavskii. More than 120 projects of various nuclear power installations were developed under the scientific leadership of the IPPE for submarine, terrestrial, and space applications, including two water-cooled power units at the Beloyarsk NPP in Ural, the Bilibino nuclear cogeneration station in Chukotka, crawler-mounted transportable TES-3 power station, the BN-350 reactor in Kazakhstan, and the BN-600 power unit at the Beloyarsk NPP. Owing to efforts taken on implementing the program for developing fast-neutron reactors, Russia occupied leading positions around the world in this field. All this time, IPPE specialists worked on elaborating the principles of energy supertechnologies of the 21st century. New large experimental installations have been put in operation, including the nuclear-laser setup B, the EGP-15 accelerator, the large physical setup BFS, the high-pressure setup SVD-2; scientific, engineering, and technological schools have been established in the field of high- and intermediate-energy nuclear physics, electrostatic accelerators of multicharge ions, plasma processes in thermionic converters and nuclear-pumped lasers, physics of compact nuclear reactors and radiation protection, thermal physics, physical chemistry and technology of liquid metal coolants, and physics of radiation-induced defects, and radiation materials science. The activity of the institute is aimed at solving matters concerned with technological development of large-scale nuclear power engineering on the basis of a closed nuclear fuel cycle with the use of fast-neutron reactors (referred to henceforth as fast reactors), development of innovative nuclear and conventional technologies, and extension of their application fields.

CFD-Modeling of Heavy Oil Injection into Blast Furnace - Atomization and Mixing in Raceway-Tuyere Area

Auxiliary fuel injection into the air blast benefits blast furnace operation by reducing coke consumption and carbon dioxide emissions, stabilizes process, and increases productivity. Heavy oil is a side stream product of petrochemical industry and it is used to replace part of the coke. Atomization of the heavy oil and mixing it with the air blast is one of the main challenges that limit high injection rates. The aim of this work is to develop CFD model of the raceway-tuyere area of the blast furnace that provides knowledge about droplet sizes and mixing behavior of the heavy oil with air blast. Atomization of the heavy oil is modeled with Wave Breakup Model, where breakup time and droplet size constants have been adjusted and validated using experimental results from physical set-up. CFD models based on the physical set-up and the actual blast furnace were made. Wave Breakup Model coupled with the CFD has good agreement with the experimental study in physical set-up. Further, CFD model is applied to study the actual blast furnace with heavy oil injection. The droplet volume median diameters in a function of the dimensionless air blast velocity are consistent in both cases having valid dynamic similarity. Mixing between the air blast and the heavy oil is poor without nozzle and most of the liquid mass is concentrated in the center of the air blast. With increasing the air blast velocity mixing gets poorer. According to modeling work, improved mixing and atomization was achieved with alternative nozzle geometries used in the tip of the oil lance.

Artificial cochlea and acoustic black hole travelling waves observation: Model and experimental results

An inhomogeneous fluid structure waveguide reproducing passive behaviour of the inner ear is modelled with the help of the Wentzel–Kramers–Brillouin method. A physical setup is designed and built. Experimental results are compared with a good correlation to theoretical ones. The experimental setup is a varying width plate immersed in fluid and terminated with an acoustic black hole. The varying width plate provides a spatial repartition of the vibration depending on the excitation frequency. The acoustic black hole is made by decreasing the plate׳s thickness with a quadratic profile and by covering this region with a thin film of viscoelastic material. Such a termination attenuates the flexural wave reflection at the end of the waveguide, turning standing waves into travelling waves.

The Variable Stiffness Actuator vsaUT-II: Mechanical Design, Modeling, and Identification

In this paper, the rotational variable stiffness actuator vsaUT-II is presented. This actuation system is characterized by the property that the apparent stiffness at the actuator output can be varied independently from its position. This behavior is realized by implementing a variable transmission ratio between the internal elastic elements and the actuator output, i.e., a lever arm with variable pivot point position. The pivot point is moved by a planetary gears mechanism, which acquires a straight motion from only rotations, thereby providing a low-friction transmission. The working principle details of the vsaUT-II are elaborated and the design is presented. The actuator dynamics are described by means of a lumped parameter model. The relevant parameters of the actuator are estimated and identified in the physical setup and measurements are used to validate both the design and the derived model.

Using MATLAB and COMSOL Multiphysics for Optimization of the Model of Underground Thermal Processes at Old Mining Dumps

The paper deals with the use of MATLAB and COMSOL Multiphysics environments for solution of optimization problem regarding underground thermal processes occurring at the old mining dumps affected by subsurface endogenous fires. It gives the description of measurement system and physical setup of the experimental borehole used to provide the real measured data for the model with the aim of its verification. The optimization problem is defined and solved by proposed computational technique that uses both MATLAB and COMSOL Multiphysics with the LiveLink tool that integrates these environments. Results of the optimization help to evaluate the total or relative heat power of the mass within mining dump.

精密测量中的量子极限

Given a physical setup, what is the precision that can be obtained? In this paper, we firstly review the recently theoretical developments about the quantum parameter estimation. The measurement sensitivity can be improved from the Heisenberg limit (HL) to super-Heisenberg limit (SHL) by changing the coupling Hamiltonian from linear to nonlinear. Then we review some techniques which have been used to break through the standard quantum limit (SQL) and reach the HL in optical quantum metrology, and describe the experiment of nonlinear quantum metrology where the interaction among particles as a valuable resource can contribute to measurement sensitivity and give scaling beyond the HL. Finally, we introduce a potential new approach to the future developments of quantum metrology.

The Importance of Somatosensory – Functional Development in Preventing Posture Deficiencies among Students in Higher Technical Education

The development of modern society is dependent to a large extent on the way in which education can meet the requirements accompanying that development. Today, young people must be prepared for living in a dynamic society which requires them to have a particular physical, intellectual, moral and civic setup. Young people should be healthy, harmoniously developed physically and highly skilled. Physical Education and Sports practiced in schools at all levels thus becomes the fundamental form of preparation for lifelong physical education, which contributes to a healthy lifestyle, a positive way of thinking and the ability to act in the benefit of the individual and of society at large. Maintaining an adequate body posture, achieving balance between the body and the environment contributes to ensuring a good, healthy lifestyle. This study aims at assessing students from a somatic and functional point of view and identifying their postural problems. As a result of this study we will develop exercise programs aimed at preventing and correcting the occupational postural deficiencies our subjects have developed in time.

The Planning, Execution, and Evaluation of a Mass Prophylaxis Full-Scale Exercise in Cook County, IL

Increasing threats of bioterrorism and the emergence of novel disease agents, including the recent international outbreaks of H7N9 influenza and MERS-CoV, have stressed the importance and highlighted the need for public health preparedness at local, regional, and national levels. To test plans that were developed for mass prophylaxis scenarios, in April 2013 the Cook Country Department of Public Health (CCDPH) and the Triple Community (TripCom) Medical Reserve Corps (MRC) executed a full-scale mass prophylaxis exercise in response to a simulated anthrax bioterrorism attack. The exercise took place over 2 days and included the TripCom Point-of-Dispensing (POD) Management Team, volunteers from the TripCom MRC, and neighboring public health departments and MRCs. Individuals from the community volunteered as actors during the exercise, while local municipal, police, and fire personnel coordinated their responses to create the most realistic simulation possible. The exercise was designed to test the capacity of TripCom and CCDPH to implement plans for organizing municipal staff and volunteers to efficiently distribute prophylaxis to the community. Based on results from POD clinic flow, accuracy of prophylaxis distribution, and observations from evaluators, the exercise was successful in demonstrating areas that were operationally efficient as well as identifying areas that can be improved on. These include improvements to the just-in-time training for POD staff, the health screening and consent forms handed out to patients, the physical setup of the POD, and the command structure and communication for the management of POD operations. This article demonstrates the need for full-scale exercises and identifies gaps in POD planning that can be integrated into future plans, exercises, and emergency response.

Physical model and theoretical model study of level ice and wide sloping structure interactions

Wide sloping structures have many applications in ice-infested waters because of their ability to fail the incoming ice in a bending failure mode. However, the poor ice clearing ability of such structures could lead to ice rubble accumulation in front of the structure, which subsequently alters the interaction mechanism. In this paper, the mechanism of level ice interacting with wide downward sloping structures was explored through a theoretical model and a series of physical model tests. Emphasis has been placed on the effects of the rubble accumulation. Based on the observations and previous theoretical ice load calculation models, a new theoretical model that couples the rubble accumulation's effects with all of the other interaction processes was proposed in this paper. In addition, this model enables us to effectively construct the ice load's spatial and temporal variations with respect to level ice interacting with downward wide sloping structures. Afterward, the theoretical model was validated by two sets of physical model tests. One of the physical model tests featured a tactile sensor that was installed on a sloping plate, which was pushed through the model level ice. The ice load's spatial and temporal variations were measured and compared to the theoretical predictions. Another physical model test set-up was a wide sloping structure that was equipped with load cells to measure the global ice load. Based on both the experimental results and theoretical model, it was concluded that the rubble accumulation in front of the sloping structure introduces additional pressure on both the incoming ice sheet and the structure itself; this pressure greatly influences the intact level ice's failing mechanism and consequently the ice load. Furthermore, the common results from both the experimental measurements and theoretical model elucidate several important aspects of the interaction mechanisms. For instance, the maximum ice load is detected slightly below the waterline within the undeformed level ice's thickness region; the ice rotating process together with the rubble effects further transmit the ice load downward to a distance of more than three times the ice thickness; and the rubble effects together with possible secondary ice breakings during the ice rotating process were theoretically demonstrated to reduce the eventual ice breaking length.

High Level of Client Satisfaction on the Business One-Stop Program of a Local Government Unit

Satisfaction is the condition or state felt by a person who has experienced a performance(or outcome) that has fulfilled his or her expectation. This study is made to determine the level of client satisfaction on the Business One-Stop Shop (BOSS) Programof the Local Government Unit (LGU) of Island Garden City of Samal (IGACOS).Descriptive-survey method was used and the respondents were the business permit registrants whose business locations and/or residences were located within the three districts of the local government unit of IGACOS, Davao Del Norte, who were able to apply/renew their business permits on the BOSS period last January 2011. The statistical tools being used were Mean, T-test, Anova and Standard Deviation.The results showed that the level of client satisfaction in terms of Physical Set-up, Systems and Procedures, and Frontline Personnel were high while Materials and Equipment was moderate. Further, there were no significant differences on the levels of client satisfaction when the respondents were classified according to type of client and when classified according to district.Keywords: Social Sciences, client satisfaction, business one-stop shop program, descriptive survey, Island City, Philippines, Asia