bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study of U-Bolt Pipe Whip Restraint: Deformation Process and Energy Absorbing
Authors: Luo Xiao , Du Wenjing , Wang Chunlin , Liu Chengyi , Yang Jie , Li Peiyu , Zhang Jinhuan
Published: March 2016

This paper focuses on the U-bolt pipe whip restraint in the industrial plants, which is used to protect the equipment and prevent chain destruction under the circumstance that the pipe whip phenomenon occurs. And to achieve better protection performance the deformation process and energy absorbing situations are studied through experiments. The experiments are able to simulate the whipping pipe impacting the U-bolt pipe whip restraint with different velocity and input energy. This study presents a novel experiment method using a rigid sled to impact the U-bolt pipe whip restraint. This horizontal impact experiment method allows to change the mass and the impact velocity of the sled easily, so it is more convenient to design and control the experiments than traditional vertical experiment method. Results of ten experiments are analyzed in this study, and some basic parameters are achieved. A significant conclusion is found that the process of the U-bolt pipe whip restraint deformation and energy absorbing has four obvious phases. Velocity effect and mass effect are also taken into account to find more details of this process. The deformation and energy absorbing law can also be used in engineering design.
Controlled-Fabrication of Sandwich-Structured NiO/Ni/NiO Nanotube Arrays for Energy Storage
Authors: Zhang Manman , Li Ben Q.
Published: March 2016

An experimental study is presented on designing and electrochemical fabrication of sandwich-structured NiO/Ni/NiO nanotube arrays for suppercapacitor applications. The electrochemical performance of different NiO based electrodes with different values of specific capacitance has been reported, including NiO film (∼309 F g−1)[1], NiO nanosheets (∼600 F g−1)[2], NiO nanotubes (∼266 F g−1)[3] and NiO-TiO2 based nanotubes (∼300 F g−1)[4]. These reported pseudocapacitors are still far from the theoretical value of NiO based capacitance, which is largely attributed to the poor electronic conduction. To overcome this difficulty, we designed and fabricated novel sandwich-structured NiO/Ni/NiO nanotube arrays as pseudocapacitor electrodes on conductive substrates. Fabrication of these nanotube arrays starts with the growth of ZnO nanorods, which then act as sacrificial template. The Ni nanotube arrays subsequently are synthesized by electrodeposition of a Ni layer onto the surface of ZnO nanorods, followed by dissolving the sacrificial template in sodium hydroxide aqueous solution. The final sandwich-structured NiO/Ni/NiO nanotube arrays are then formed by annealing of the Ni nanotubes at temperature of 450°C in air. The aspect ratio of the Ni nanotubes is conformable with the morphology of the ZnO nanorods template and their wall-thickness is determined by the electrodeposition. The thickness of the NiO layer can be further controlled by adjusting the processing parameters of the annealing process (i.e., time and temperature). The results of electrochemical tests, that is, the cyclic voltammetry and galvanostatic charge-discharge cycling measurements, show that the NiO/Ni/NiO sandwich-like nanotubes electrode clearly displays pseudo-capacitive behavior with improved capacitive performance. Experimental data suggest that the metal Ni core in the NiO/Ni/NiO sandwich-like nanotube structures uniquely serves as a channel for high electron transfer rate from current collector to support the rapid redox reaction activated in the bilateral NiO shells with a higher electrolytic accessible surface area, which is responsible for the high performance of energy storage.
Molecular Dynamics Study of DNA Translocation Through Graphene Nanopores With Controllable Speed
Authors: Li Kun , Si Wei , Sha Jingjie , Chen Yunfei
Published: March 2016

All-atom steered molecular dynamics (SMD) simulations provide the means to study the single-stranded DNA (ssDNA) translocation through graphene nanopores at a controllable speed. The ssDNA is pulled by an elastic force similar to the manipulation by an AFM tip. At the same time, an electric field is applied across the reservoir along the direction of the pulling force, in order to hold the ssDNA strand taut and drive the ions in the solutions through the nanopore. By monitoring and analyzing the average ionic current blockage of poly(dA)10, poly(dC)10, poly(dG)10 and poly(dT)10, it is found that one can indeed discriminate the different DNA bases from each other by holding each nucleotide in the pore for sufficiently long time. It is obtained the average blocked ionic currents can be listed, in a increasing order, as IG<IAVA>VT>VC), apart from C. The results indicate that physical occupancy of the nucleotide plays the major role in affecting average blocked ionic current when the DNA translocation speed is effectively slowed down. This work provides a clue for the further investigation to realize the discrimination of the four nucleotides by the method of actively controlling DNA molecule translocation speed through the nanopores.
Gannon Exoskeleton for Arm Rehabilitation (G.E.A.R.)
Authors: Piovesan Davide , Arumugam Yuvarajan , Jackson Corey , Shanmugam Santhosh Kumar , Restifo Adam , Legters Kristine
Published: March 2016

A low cost continuous passive motion (CPM) machine, the Gannon Exoskeleton for Arm Rehabilitation (GEAR), was designed. The focus of the machine is on the rehabilitation of primary functional movements of the arm. The device developed integrates two mechanisms consisting of a four-bar linkage and a sliding rod prismatic joint mechanism that can be mounted to a normal chair. When seated, the patient is connected to the device via a padded cuff strapped on the elbow. A set of springs have been used to maintain the system stability and help the lifting of the arm.

In this work a multi-body simulation was performed with the software SimWise 4D by Design Simulation Technologies (DST). The simulation was used to determine the stiffness of the springs in the mechanism to provide assistance to raising of the patient’s arm. Furthermore, the software can provide a finite element analysis of the stress induced by the springs on the mechanism and the external load of the arm. Finally, a physical prototype of the mechanism was fabricated using PVC pipes and commercial metal springs. Due to the low cost of fabrication, simplicity, and ease of adjustability, it is believed that the GEAR has the potential to provide effective passive movement to individuals who otherwise would not have access to post-operative or post-stroke rehabilitation therapy.
Effect of Ovality on the Collapse Pressure of a Subsea Pipeline at High Outer Diameter-to-Wall Thickness Ratios
Authors: Natarajan Valliyappan David , Ayob Arif Ashraf
Published: March 2016

Subsea pipelines are primarily used in the transportation of oil and gas from the excavation site to the oil refinery. These pipelines are usually put under immense internal and external ambient pressures during their operation. The pipelines are therefore designed to account for the supported pressure and to ensure lower in-service failure probability. However, manufacturing issues arising from precision of machine tools and residual stresses in raw materials tend to cause the physical pipes to be geometrically imperfect. Imperfections including ovality (out-of-roundness), uneven wall thickness and longitudinal eccentricity (conical sections) may render the original design unsafe during the operation of the pipes. Experimental observations indicate that the collapse of pipeline pressure can be potentially overestimated if the geometrical imperfections are not considered in the design. Finite element analysis (FEA) that includes the geometrical imperfections in the pipeline model gives a better estimation of the collapse pressure. This study is aimed at modeling the ovality of a selected subsea pipeline and investigating its effect on the circumferential pressure distribution on the internal and external walls of the pipes using FEA. The collapse pressures of the pipeline are determined as a function of its outer diameter-to-thickness (D/t) ratios as well as the ovality. The type of ovality considered is full ring with 3%, 5% and 7% ovality. The FEA is performed using the Abaqus™ (ver. 6.12) software package and the collapse pressure for six D/t ratios between 30 and 80 (at a stepwise increase of 10) are determined based on the von Mises yield criterion of AISI 1009 carbon steel. Simulation results indicate that the collapse pressure reduces with the D/t ratio for all percentages of ovality. It is also observed that greater ovality gives smaller values of collapse pressure. For example, the collapse pressures of the pipe with D/t = 30 are 9.08 MPa, 8.64 MPa and 7.91 MPa for 3%, 5% and 7% ovality of the full ring type, respectively. The simulation results are compared against analytical results obtained using relevant formulas from two standards, i.e. BS 8010-3 and API 1111. The discrepancies between the simulation and API 1111 analytical results reduces for pipes with D/t = 60 and higher. The lowering of the collapse pressure would lead to unpredicted failure of pipelines if the effect of initial ovality in the pipe is not considered in the geometrical model for FEA. It is therefore imperative that ovality of pipes be kept to a minimum. Buckle arrestors may be placed on the pipe to limit the effect of ovality on the collapse pressure of the pipe.
Design Perception: Combining Semantic Priming With Eye Tracking and Event-Related Potential (ERP) Techniques to Identify Salient Product Visual Attributes
Authors: Rojas Juan-Carlos , Contero Manuel , Camba Jorge D. , Castellanos M. Concepción , García-González Eva , Gil-Macián Sandra
Published: March 2016

The study of product visual attributes is usually performed through questionnaires which provide information about the conscious subjective opinions of the consumer. This work complements such method by combining Event-Related Potentials (ERP) and Eye-Tracking (ET) techniques and using semantic priming to elicit user perception. Our study focuses on package design and follows the basic structure of classic ERP experiments where participants are presented an ordered sequence of frames (stimuli) in a computer screen for a certain period of time: attention frame, semantic priming frame (descriptive adjective), neutral background, target frame (product image), and a question regarding coherence between priming and target frames. The eye-tracking system works in combination with the ERP experiment. The results of our study reveal the connection between adjectives (semantic priming) and package design attributes (based on the analysis of the N400 ERP component), and the connection between adjectives and the specific visual elements that get more attention (based on the information provided by eye-tracking analysis software).
Technical and Economic Analyses for Sizing PV Power Plant With Storage System for METU NCC
Authors: Sadati S. M. Sajed , Jahani Elham , Taylan Onur
Published: March 2016

The use of renewable energy with storage systems is particularly important in small and unreliable grids, such as islands. This paper reports sizing of a photovoltaic (PV) power plant with storage system for Middle East Technical University Northern Cyprus Campus through technical and economic analyses. PV system was modeled considering fixed tilted, one-axis and two-axis tracking systems using hourly data. Energy storage system was included in the model to overcome the temporal mismatch between the electricity demand of the campus and the electricity supplied by the PV system. The reduction in CO2 emissions by deploying these systems was studied. The results showed that although it would not be economically feasible to meet the entire demand of the campus, a PV system of 4.5 MW with 15 MWh of storage size would generate enough electricity to meet the demand for 83% of the time in a year, yielding the cost of 0.25 USD/kWh.
Augmenting an Educational and Research Human Robot Interaction Environment With a Multi-Obstacle Avoidance Algorithm
Authors: Ábrego Christopher E.
Published: March 2016

In this manuscript, the development and current state of an inexpensive platform for educational purposes and research in the interaction between humans and robots (human-robot interaction) is described. The platform is based on the ubiquitous LabVIEW programming language and an in-house developed two degree of freedom non-holonomic robot. The platform includes multiple interaction modalities, which will be described, between the robot and the user.

The procedures followed for the successful software and hardware implementation are explicated. Furthermore, a demonstration of an obstacle avoidance path planning algorithm for a single obstacle is validated in hardware, as well as simulation demonstration of the multiple obstacle avoidance algorithm. These implementations to the platform further demonstrate the ease of augmenting the existing platform to additional modalities.

The algorithm uses a vision acquisition system to identify the location and size of an obstacle, in addition to orientation patterns and calibration points, in the workspace and generate the robot path to reach a desired goal while avoiding the obstacle. The manuscript describes into the current research of path planning in the presence of multiple obstacles. The development of a set of criteria, Generation Succession, Arrival Departure, and Side Consistency, for the algorithm are elucidated in the manuscript. The algorithm has been demonstrated to be successful in simulation by avoiding multiple obstacle in various layouts.
Atomic Force Microscopy of Annealed Plain Carbon Steels
Authors: Gupta Surendra Kumar , Iglesias Victoria Patricia
Published: March 2016

Microstructure of annealed plain carbon steels is examined using optical microscopy. When the inter-lamellar spacing in pearlite is small, optical microscope at 1000X is unable to resolve the ferrite and cementite lamellae. In hyper-eutectoid steels, cementite in pearlite appears as darker phase whereas the pro-eutectoid cementite appears as a lighter phase. Atomic force microscopy (AFM) of etched steels is able to resolve ferrite and cementite lamellae in pearlite at similar magnifications. Both cementite in pearlite as well as pro-eutectoid cementite appear as raised areas (hills) in AFM images. Interlamellar spacing in pearlite increases with increasing hardenability of steel.
Axiomatic Product Design in Three Stages: A Constituent Roadmap That Visualises the Status of the Design Process by Tracking the Knowledge of the Designer
Authors: Puik Erik , Ceglarek Darek
Published: March 2016

Increasing global competition in manufacturing technology puts pressure on lead times for product design and production engineering. By the application of effective methods for systems engineering (engineering design), the development risks can be addressed in a structured manner to minimise chances of delay and guarantee timely market introduction. Concurrent design has proven to be effective in markets for high tech systems; the product and its manufacturing means are simultaneously developed starting at the product definition. Unfortunately, not many systems engineering methodologies do support development well in the early stage of the project where proof of concept is still under investigation. The number of practically applicable tools in this stage is even worse. Industry could use a systems engineering method that combines a structured risk approach, concurrent development, and especially enables application in the early stage of product and equipment design. The belief is that Axiomatic Design can provide with a solid foundation for this need. This paper proposes a ‘Constituent Roadmap of Product Design’, based on the axiomatic design methodology. It offers easy access to a broad range of users, experienced and inexperienced. First, it has the ability to evaluate if knowledge application to a design is relevant and complete. Secondly, it offers more detail within the satisfaction interval of the independence axiom. The constituent roadmap is based on recent work that discloses an analysis on information in axiomatic design. The analysis enables better differentiation on project progression in the conceptual stage of design. The constituent roadmap integrates axiomatic design and the methods that harmonise with it. Hence, it does not jeopardise the effectiveness of the methodology. An important feature is the check matrix, a low threshold interface that unlocks the methodology to a larger audience.
The Application of Axiomatic Design to Complex Wi-Fi Systems
Authors: Hintersteiner Jason D.
Published: March 2016

Axiomatic Design is a technique that has been applied to multiple disciplines for enabling design, analysis, and troubleshooting of complex systems. In this paper, the principles of Axiomatic Design are applied to Wi-Fi networking. Wi-Fi is the information backbone for numerous applications, including Internet connectivity, video surveillance, data collection and inventory tracking in manufacturing and warehouse environments, patient location and health status monitoring in assisted living and hospital environments, along with numerous others. A Wi-Fi system consists of multiple access points working in tandem to provide seamless, high-speed, and high-quality wireless coverage to one or more wireless client devices. To implement such a network effectively, the Wi-Fi engineer must understand and control the interactions between multiple engineering disciplines, most notably information technology, network engineering, radio frequency physics, antenna design, and materials science. Technology development in this field is fast-paced, with new standards and capabilities being introduced into the market every couple of years. Additionally, the customer expectations (i.e. requirements) are changing as well once the Wi-Fi network is installed, as data demands from new types of devices like smartphones, tablets, and network appliances are introduced long after the original network was implemented.

This paper shows that there are three primary functional requirements for a Wi-Fi network, namely client usage type, coverage area, and client capacity. When designing, implementing, or troubleshooting a Wi-Fi network, there are four primary design parameters that can be controlled, namely AP antenna / model, location, channel, and transmission power. Axiomatic Design demonstrates that these four design parameters are coupled, and thus cannot be manipulated independently. Nevertheless, by effectively implementing Axiomatic Design techniques to define a set of best practices, these four key parameters can be decoupled and properly linked back to the requirements and constraints of the system to simplify the design, implementation, and troubleshooting of a Wi-Fi network.
A Quadruped Robot Powered With Pneumatic Actuators
Authors: Heim Isaac , Zheng Hao , Shen Xiangrong
Published: March 2016

This paper presents the design and control of a quadruped robot, which uses pneumatic actuators to power the eight joints in the robot. Leveraging the high performance of pneumatic actuators, the quadruped is able to provide the desired torque and power output while keeping the robot compact and lightweight. The ultimate purpose for the quadruped is to assist and accompany its human user in the daily life. As such, the overall design of the quadruped takes inspiration from human lower limbs, i.e., the quadruped can be imagined as the combination of two pairs of human lower limbs in opposite directions. The design details of the robot are presented, including the hip and knee joints and their actuation mechanisms. The control scheme is also presented, in which the robotic joints follow similar trajectories of their human biological counterparts. In the preliminary testing, the quadruped robot was able to walk continuously at a stable gait, demonstrating the effectiveness of the robot design and control approaches.
Development and Application of Planar Computational General-Purpose Constrained Multibody Simulations in MATLAB With Simple Graphical/Visualization Capability
Authors: Dye J. R. , Tay Y. Y. , Lankarani H. M.
Published: March 2016

This study demonstrates the implementation and advantages in utilizing the Matlab programming environment for general-purpose simulations of constrained planar dynamic and kinematic multibody mechanical systems. Many currently available tools have a focus and can have limited flexibility through difficulty in data entry, limited access to source code, analysis of data or use of programming languages not readily taught. A Matlab source code is created, which includes the use of Microsoft Excel and GUI’s created in GUIDE that allow a user to construct, simulate and analyze multibody systems in Matlab. This technique allows the user to utilize any of Matlab toolboxes for unique problems or integrate the base program into a Simulink environment. An overview of the general code structure and multibody kinematics and dynamics equations used are shown in this paper. For kinematic simulations, the system’s Cartesian coordinates are found by finding the roots of the constraints vector at each time step. For the dynamic systems, the solver uses a numerical integration scheme with augmented form of the constrained equations of motion to solve for the system’s accelerations. Examples are presented demonstrating the benefits of using the Matlab environment and the flexibility to easily expand the code to simulate unique problems. These examples include an Ackermann steering for automotive applications and a double pendulum at the influence of gravity. The last example shows how a custom function can be created to inject forces into the dynamic solver in order to simulate a structural beam at the influence of a heavy pendulum.
Development of an Under-Actuated Robotic Device for Knee Loading Applications
Authors: Korupolu Sandeep , Anwar Sohel , Yokota Hiroki , Chien Stanley
Published: March 2016

Mechanical stimuli are crucial for the growth, development, and maintenance of articular cartilage and bone. This paper investigates a novel mechanical loading device with position specific loading capability for stimulating articular cartilage and bone. It proposes a design of an under-actuated multi-fingered robotic hand for achieving such a joint loading. The robotic hand has 8-degrees of freedom and is operated by a single motor. Four fingers, each having two phalanges were designed. The fingers are connected through shafts and are operated using a slider crank mechanism. The CAD model was constructed in Creo and then exported to Simmechanics, a toolbox in MATLAB / SIMULINK module where dynamic force analysis was performed. The simulation results validate that the device can produce the necessary magnitude of forces at required frequencies to promote the stimulation of articular cartilage and bone growth.
Effects of Wall Shear and Rayleigh-Taylor Instabilities on a Gas-Liquid Interface in a High-Speed Multiphase Flow
Authors: Adam Carlton , Hadim Hamid
Published: March 2016

A numerical simulation is performed to predict the multiphase flow structure of a slug of liquid salt water as it is accelerated through a launch tube by high-pressure, high-temperature gas. This effort is performed to support the design of recoilless launch systems, in which the momentum produced by the launch of a solid projectile is balanced by the ejection of a liquid countermass in the opposite direction. Careful design of the countermass can reduce the net recoil of the launch system to nearly zero, thus allowing higher launch energies to be obtained from relatively light platforms. Simulating the behavior of the liquid countermass during the launch cycle is important for predicting net recoil, as well as for calculating the overall performance of the launch system.

The current work builds on previous efforts to analyze the liquid slug ejection by considering the fluid system in three dimensions and by recognizing the importance of surface tension and mesh refinement at the gas-liquid interface. Effects of shear stress at the slug-wall interface are considered, as are Rayleigh-Taylor instabilities that arise due to the high acceleration and large density differences of the gas and liquid phases.

A transient 3D simulation of the launch event is performed using the VOF (volume of fluid) method to track the gas-liquid interface, while a realizable k-ε model is used to calculate turbulent viscosity in both the gas and liquid phases. The initial conditions of the simulation are that the liquid slug is initially at rest, and that a relatively flat and uniform gas-liquid interface discretely separates the two phases. The properties of the driving gas are calculated a priori using a separate combustion model. The driving gas enters the computational domain of the fluid model as an inlet boundary condition, specified by an entrance pressure as a function of time. The simulation is allowed to run until the bulk of the liquid slug has exited the tube into the atmosphere.

The predicted flow properties, including liquid volume fraction, pressure, velocity, and temperature fields as functions of time are reported. The predicted structure and velocity of the exiting slug are compared to measurements taken using high-speed video during empirical testing of a representative launch system. Gas pressures inside the tube during the launch cycle are compared to electronic pressure data collected from the same test. There is excellent agreement between the predicted and empirical exit velocity of the liquid slug, though the video data shows a higher degree of atomization of the liquid than is predicted by the model.
The Effects of Inlet Turbulence Intensity Levels and Computational Domains on Non-Premixed Bluff-Body Flame
Authors: Chen Lu , Battaglia Francine
Published: March 2016

The bluff-body stabilized flame provides an ideal case to investigate the interactions between chemical reactions and turbulence. This paper uses CFD to study the effects of inlet turbulence intensity levels for boundary conditions and compare 2D axisymmetric and 3D geometries on the non-premixed turbulent combustion characteristics. The predictive capabilities of the k-ε turbulence model are evaluated and compared with the experiments of Correa and Gulati for a bluff-body flame of 27.5%CO/32.3%H2/40.2%N2 and air [1]. The assessment of the modeling techniques with the study of inlet turbulence intensity and between computational domains is compared with experimental profiles. Results showed that the inlet turbulence intensity in the fuel-jet had a substantial impact on the axial decay of mixture fraction and temperature, which did not support the conclusion Correa and Gulati [1] that the flow was relatively insensitive to the inlet profiles. The inlet turbulence intensity of 4% was used to compare the value assumed by Hossain [2] and the results showed a great improvement around the fuel jet inlet and axial profiles. The numerical results of the 2D axisymmetric and 3D domains showed that the 3D domain provided better predictions, which is consistent with Shih et al.[3] that the prediction of axisymmetric jets is unexpectedly poor for the k-ε turbulence model due to the underestimation of the dissipation. Further analysis in terms of velocity and strain rate distributions was also conducted to better understand the effects of turbulence intensity levels and computational domains on mixing and fluid dynamics in the reaction zone. Radial velocity results along the centerline provided the reason for the differences between computational domains, for which 2D axisymmetric simulations underestimated the radial velocity magnitude along the centerline. Central profiles of strain rate showed the change of flow and mixing by different turbulence intensity levels.
Convective Heat Transfer in the Stagnation Zone of an Axisymmetric Upward Jet Impinging on a Stationary Flat Surface
Authors: Soltis Dennis , Sangeorzan Brian
Published: March 2016

Experiments were conducted to measure the local heat transfer coefficient in the stagnation zone of an upward, free oil jets impinging upon a stationary, heated flat surface. Six tube-style nozzles were used having diameters ranging from 0.864 mm to 3.073 mm. The oil viscosity ratio, based upon the nozzle and surface temperatures, varied from 0.472 to 0.903. The fluids tested included Prandtl numbers ranging from 62 to 142, and by varying the flow rate the Reynolds number ranged from 268 to 3,810. Testing demonstrated that the Reynolds number, which includes the nozzle diameter as the characteristic length, did not account properly for the effect of nozzle diameter on the heat transfer rate. Introduction of the Bond number into the Nusselt number correlation did allow a good correlation for all nozzle diameters.
Hemodynamics Numerical Simulation of Stenosis Bifurcation
Authors: Chaudhari Krunal , Patel Hardikkumar
Published: March 2016

The main purpose of this research is to analyze blood flow in various scenarios such as 20%, 50% and 80% blockage in blood vessel due to aortic atherosclerosis. Valuable Information for clinical diagnosis of cardiovascular diseases can be obtained by analyzing the behavior of blood flow and its variations. An idealized numerical model of the human bifurcated aorta is created then simulations of steady blood flow were performed on this model and various parameters have been considered. The model parameters include the blood flow velocity, pressure, wall shear stress (WSS) of vessels, constant blood density and constant viscosity. The data computed from software indicates behavior of blood flow according to changes in physical properties of blood vessel. These results are mostly similar to physiological and pathological results of vessels observed in clinical practice. This study will eventually help to find the Fluid Structure Interaction (FSI) of blood flow and blood vessel which will be bring a favorable change in cardiovascular diseases treatments.
Synthesis and Analysis of Electrically Sensitive Hydrogels for Advanced Drug Delivery Systems
Authors: Usta Aybala , Asmatulu Ramazan
Published: March 2016

Electrically sensitive polyvinyl alcohol (PVA) hydrogels loaded with methotrexate (MTX) were prepared via a solution casting process, and characterized by attenuated total reflectance (ATR) spectrometry. In order to determine if the hydrogels were electro-sensitive or not, bending tests were conducted on the sulfoacetic acid modified hydrogels. It was observed that the prepared samples into strip forms started bending towards the cathode, and this bending was reversible when the polarity of the applied voltage was changed. The drug release study was performed on the MTX-loaded hydrogel strips placed in a sodium chloride (NaCl) solution under three different voltages (e.g., 0V, 5V, 10V, and 20V). Subsequently, the solutions were collected every five minutes in order to determine the drug release behaviors of the hydrogels using an ultraviolet-visible (UV-Vis) spectrophotometer. The test results showed that sulfoacetic acid (SA)-modified PVA hydrogels possess electrical sensitive behavior and kept their electric sensitivity for a long period of time. Also, the results confirmed that the control drug release could be achieved under different electrical voltages.
On Controlling Non-Autonomous Time-Delay Feedback Systems
Authors: Kuo Chi-Wei , Suh C. Steve
Published: March 2016

Time-delay feedback oscillators of non-autonomous type are considered in the paper. These oscillators have been studied extensively for many decades in a broad set of fields such as sensor design, manufacturing, and machine dynamics. A time-delay model system having one time-delay constant and several nonlinear feedback terms in the governing differential equation is first studied. Many researches have demonstrated that a time-delay feedback even in the form of a small perturbation is able to perturb the oscillator to exhibit complex dynamical responses including bifurcation and route-to-chaos. These motions are harmful as they have a very negative impact on the stability, and thus output quality, of the system. For example, manufacturing processes that are characterized by time-delay feedback all have an operation limit on speed because the chaotic behaviors which are unpredictable and extremely unstable are difficult to control. With a viable control solution, the performance, quality, and capacity of manufacturing can be improved enormously. A novel concept capable of simultaneous control of vibration amplitude in the time-domain and spectral response in the frequency-domain has been demonstrated to be feasible for the control of dynamic instability including bifurcation and route-to-chaos in many nonlinear systems. The concept is followed to create a control configuration that is feasible for the mitigation of non-autonomous time-delay feedback oscillators. Featuring wavelet adaptive filters for simultaneous time-frequency resolution and filtered-x least mean square algorithm for online identification, the controller design is shown to successfully moderate the dynamic instability of the time-delay feedback oscillator and unconditionally warrant a limit cycle. The controller design that integrates all these features is able to mitigate dynamical deterioration in both the time and frequency domains and properly regulate the responses with the desired reference signal. Specifically the qualitative behavior of the controlled oscillator output follows a definitive fractal topology before settling into a stable manifold. The controlled response is categorically quasi-periodic and of the prescribed vibration amplitude and frequency spectrum. The control scheme is novel and requires no linearization. By applying wavelet domain analysis approach to the nonlinear control of instability, the true dynamics of the time-delay feedback system as delineated by both the time and frequency information are faithfully retained without being distorted or misinterpreted. Through employing adaptive technique, the high sensitivity of the time-delay feedback system to external disturbances is also properly addressed.
Graduation Design Project: Designing and Building a Pin-on-Disk Tribometer
Authors: Ochs Elspeth , Iglesias Victoria Patricia
Published: March 2016

The purpose of this paper is to describe an independent study project required before graduation with a master of engineering degree in the department of mechanical engineering at Rochester Institute of Technology. The goal of this graduation project was to design and build a Pin-on-Disk Tribometer. The tribometer will be used by the department for future student research projects. This paper includes the details of the design process, such as adaptations from existing tribometers, all required calculations, and descriptions of the machining and assembly. New design concepts presented demonstrate simplicity of construction and use. The required calculations include shear and bending moments in the arm, bearing calculations, lead screw load analysis, counterweight balancing, torque calculations for selecting the correct motor, and strain calculations for determining the correct strain gage set-up. The paper details part selection, pricing, machining, and assembly. Mistakes and alternate design considerations are also discussed.
A Mathematical Model of an Active Gyroscopic Roll Stabilizer Using the Moving Frame Method
Authors: Rios Oscar , Murakami Hidenori
Published: March 2016

Large offshore renewable energy investments require the use of maintenance boats to keep them in operable conditions. Unfortunately, due to rough seas in some of the project locations, the transferring of crew members from vessel to turbine or platform is no easy task. Thus, the research presented is focused at further looking into add on stability systems for marine vessels to further ease the process of offshore platform maintenance and crew member safety.

The rolling and pitching of ships and boats induced by the ocean waves results in undesirable motion. In an effort to increase the stability of the deck/platform and human comfort and safety, various add-on stability systems have been developed. Of interest in the research presented are internal active systems, specifically the active gyroscopic stabilizer.

Previous research and industrial use of active gyroscopic roll stabilizers has shown and proven the effectiveness of the system to reduce rolling motion. The research presented here is focused on developing a more detailed mathematical analysis of a marine vessel installed with active gyroscopic roll stabilizer(s). Through the use of the moving frame method developed by the second author, a novel approach has been developed to derive a mathematical model for two different cases: 1) a marine vessel with a single gyroscopic roll stabilizer and 2) a marine vessel with two gyroscopic roll stabilizers. The moving frame method allows for a systematic derivation despite the increase in complexity of the system as the number of stabilizers is increased. Lastly, the nonlinear equations of motion of a ship with a gyroscopic roll stabilizer are derived.
New Background of Micromechanics of Random Heterogeneous Media: Opportunities and Prospects
Authors: Buryachenko Valeriy A.
Published: March 2016

One considers a linear heterogeneous media (e.g. filtration in porous media, composite materials, CMs, nanocomposites, peristatic CMs, and rough contacted surfaces). The idea of the effective field hypothesis (EFH, H1, see for references and details [1], [2]) dates back to Mossotti (1850) who pioneered the introduction of the effective field concept as a local homogeneous field acting on the inclusions and differing from the applied macroscopic one. It is proved that a concept of the EFH (even if this term is not mentioned) is a (first) background of all four groups of analytical methods in physics and mechanics of heterogeneous media (model methods, perturbation methods, self-consistent methods, and variational ones, see for refs. [1]). An operator form of the general integral equations (GIEs) is obtained which connects the driving fields and fluxes in a point being considered. New GIEs present in fact the new (second) background (which does not use the EFH) of multiscale analysis offering the opportunities for a fundamental jump in multiscale research of random heterogeneous media with drastically improved accuracy of local field estimations (with possible change of sign of predicted local fields).
Load Transfer Index for Composite Materials
Authors: Wang Qingguo , Pejhan Khashayar , Wu Christine Q. , Telichev Igor
Published: March 2016

Load transfer analysis is a new paradigm for lightweight vehicle design. U* index has been proved to be an effective indicator for the load path. The U* theory indicates that the external loading mainly transfers through the parts with higher U* values in the structure. However, the fundamental equations of the theory are based on isotropic, homogenous, and linear elastic assumptions for the materials. Consequently, U* index is inadequate for composite materials which are increasingly used in automotive structures. In this study, a new load transfer index for composite structures, U*O, is proposed for the first time inspired by the basic U* theory. The U*O index considers the composite material as orthotropic instead of isotropic and eliminates the limitation of the basic U*. The effectiveness of the new U*O index on load path prediction is demonstrated by a case study for a general Graphite-epoxy lamina. The U*O index is capable to evaluate the accurate load path for the composite specimen. By contrast, the basic U* analysis shows the incorrect results.
Experimental Study of U* Index Response to Structural and Loading Variations
Authors: Pejhan Khashayar , Wang Qingguo , Telichev Igor
Published: March 2016

Load transfer analysis tracks the path, on which the imposed load is being carried through the structure. Recently, vehicle structure designers have paid growing attention to this aspect of structural analysis for designing lighter vehicle structures that can efficiently carry the imposed loads with minimum weight. There are two main procedures for load transfer analysis in automotive engineering: 1) Stress trajectory method and 2) U* index theory. The former method faces some difficulties in following load path in structures with stress concentrations made by geometrical irregularities. As a result the U* index theory has been utilized more frequently in this area. This theory has shown exceptional capacities in following load transfer in the structure and has provided innovative tools for design modification in automotive industry. Although it can be shown mathematically that U* index quantifies the internal stiffness of the structure there has not been an experimental validation for that. Moreover, the term internal stiffness itself is not an easy concept to follow and it can be easily mistaken for the structural stiffness of the structure. As a result in the current paper two experimental testing procedures are presented to distinguish the internal stiffness, that can be quantified with U* index and the structural (conventional) stiffness of the structure. Through these experiments, for the first time, physical evaluation of U* index response to loading and structural variations can be performed.
Numerical Simulation of Polymeric Gels
Authors: Chester Shawn A.
Published: March 2016

Following [1], a theory for coupled fluid diffusion and large deformation is implemented as a user-element subroutine in the commercial finite element package ABAQUS. The governing equations are summarized along with details of the constitutive theory. A few numerical examples are provided to show the robustness of this methodology in both transient and steady state conditions.
A Leader-Following Formation Control of a Group of Forklift-Like Mobile Robots
Authors: Lee Ho-Hoon
Published: March 2016

This paper proposes a leader-following formation control for a group of forklift-like mobile robots. The leader follows its desired trajectory while the rest of robots are following the leader in a specified formation. The proposed formation control computes desired driving force and steering torque for each robot. The proposed control consists of a formation control scheme and a kinematic trajectory generation scheme for the leader of a group. The nonholonomic constraints of the forklift-like mobile robots are taken into account in the design of the formation control and trajectory generation schemes, in which the Lyapunov stability theorem and the loop shaping method are used as design tools. Under certain conditions, the proposed formation control guarantees asymptotic stability while keeping all internal signals bounded. The effectiveness of the proposed control has been shown with realistic computer simulations.
Personal Modular Design
Authors: Fukuda Shuichi
Published: March 2016

This is a position paper.

Although modular design is getting wide attention these days, most of the discussions and applications are focused on efficiency, cost reduction, etc., which has been regarded important in the traditional product development or in the producer’s framework. Their focus is how they can prepare wider variety with less time, money and energy. They believe if a wide variety of products are offered. the customer would select the one that would fit them best.

Thus, not too much attention is paid to the customer expectations. The current producer do not sell dreams. They just increases the choices. This can be compared to what animals are doing. Animals can use tools, but these tools are found in nature. Animals do not make tools, but humans do, because humans can see the future, while animals cannot. Engineering is an activity to satisfy customer dreams. In this sense, the current industry is not achieving what engineering is supposed to achieve.

In addition, as human needs step up, humans would like to actualize themselves. But in the earlier or lower step, their needs are products so products satisfy them. But when they step more and more upward, they find value in the processes. So products alone will not satisfy them enough. They would like to make their dreams come true by themselves.

Thus, how we can get customers involved in the production becomes important. In short, we have to consider how we can mix high tech and low tech and work them harmoniously. Some modules needs high tech. Thus expertise is needed. But others can be developed and produced by customers.

Then, customers will be very happy because they are players in the game and they feel they themselves are developing a product to realize their own dream. Of course, personal fabrication technology can be used for this purpose. But theirs and my idea are basically different. Their idea is to produce a product by ourselves. But the approach proposed here is focused on our industrial products. The issue here is how we can bring our customers into our product development, which current industries are practicing. If we can design a product, which is composed of modules which needs high tech and expertise and those which can be produced with low tech, then we can bring our customers into low tech and low expertise module production. Although customers are not producing the whole product, they feel happier because they are now making their dream come true themselves. Thus, industries can sell processes. And it should be stressed that this is not a reconfigurable design. The low tech and low expertise modules are really produced by our customers. They do not select modules to produce a product as we do with Lego.

This design of mixture of low tech module and high tech module serves for globalization as well. Some developing countries cannot produce high tech modules, because their resources are not enough. But if some modules can be produced with low tech, then they can produce them locally and that will increase employment and the market will expand.
Evaluating Functional Coupling in Aeration Basin Air Distribution Systems
Authors: Harutunian Vigain , Harutunian Anne , Harutunian Kegham A. , Harutunian Shant
Published: March 2016

Axiomatic Design provides a set of axioms and corollaries to help make system design decisions. In this paper, the independence axiom is applied to evaluate alternate low pressure air (LPA) distribution system designs to serve the aeration basins of a wastewater treatment plant. The airflow to each air zone is defined as a functional requirement (FR) in the functional domain. A design parameter (DP) in the physical domain is selected to achieve each FR. The DPs include the LPA motor operated valve (MOV) damper positions and a process air blower inlet guide vane (IGV) position. Three design alternatives are developed and evaluated with the respect to the independence axiom. Each subsequent alternative attempts to reduce the amount of functional coupling. Reduced functional coupling in an LPA system results in a more stable treatment process and greater system longevity through reduced component wear.
Tracking Microparticles Subjected to Dielectrophoresis in a Continuous Flow Microdevice
Authors: Mathew Bobby , Alazzam Anas , El-Khasawneh Bashar S. , Khashan Saud A. , Destgeer Ghulam , Sung Hyung J.
Published: March 2016

This article details the development of a two-dimensional model for tracking microparticles subjected to dielectrophoresis in a continuous flow microdevice. The electric field is generated by interdigitated transducer electrodes placed on the bottom of the microchannel. The motion of the microparticles and the electric potential inside the microchannel are described using Newton’s 2nd law and Laplace equation, respectively. The governing equations are solved using finite difference method. The model accounts for forces such as inertia, drag and dielectrophoresis. The model is used for parametric study in this article; the parameters considered include microparticle radii, actuation voltage, microchannel height and volumetric flow rate. From the parametric study it is observed that the trajectory of microparticles depends on all these parameters though only the actuation voltage, among these parameters, influences the steady state levitation height.