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This paper was removed from publication at the author’s request. February 18, 2021. Copyright © 2021 by ASME

The above referenced paper has been removed from publication at the author’s request. October 2, 2020. Copyright © 2020 by ASME

The above referenced paper has been removed from publication at author’s request. September 9, 2020. Copyright © 2020 by ASME

The above referenced paper has been removed from publication. (April 21, 2020) Copyright © 2020 by ASME

The above referenced paper has been removed from publication. (April 21, 2020) Copyright © 2020 by ASME

The above referenced paper has been removed from publication. (March 10, 2020) Copyright © 2020 by ASME

This paper has been retracted by the American Society of Mechanical Engineers due the commercial nature of the content. December 21, 2018. Copyright © 2018 by ASME

The above referenced paper has been removed from publication. (March 10, 2020) Copyright © 2020 by ASME

This erratum corrects errors that appeared in the paper “Analysis of the Performance of Plasma Actuators Under Low-Pressure Turbine Conditions Based on Experiments and URANS Simulations” which was published in Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition, Volume 2A: Turbomachinery, V02AT40A034, June 2017, GT2017-64867, doi: 10.1115/GT2017-64867.

This erratum corrects errors that appeared in the paper “Forced Response Analysis of a Mistuned Compressor Blisk Comparing Three Different Reduced Order Model Approaches” which was published in Proceedings of ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition, Volume 7A: Structures and Dynamics, V07AT32A030, June 2016, GT2016-57902, doi: 10.1115/GT2016-57902.

Microbial fuel cells (MFCs) have been a potential green energy source for a long time but one of the problems is that either the technology must be used on a large scale or special equipment have been necessary to keep the fuel cells running such as syringe pumps. Paper-based microbial fuel cells do not need to have a syringe pump to run and can run entirely by themselves when placed in contact with the fluids that are necessary for it to run. Paper-based microbial fuel cells are also more compact than traditional MFCs since the device doesn’t need any external equipment to run. The goal of this paper is to develop a microbial fuel cell that does not require a syringe pump to function. This is done by layering chromatography paper with wax design printed onto it. This restricts the fluids to a specific flow path allowing it to act like the tubes in a typical microbial fuel cell device by delivering the fluids to the chamber. The fluids are picked up by tabs that sit in the fluid and use capillary attraction to flow up the tab and into the device. The fluids are directed to the chambers where the chemical and biological processes take place. These flows are then directed out of the device so that they are taken to a waste container and out of the system. Our microliter scale paper-based microbial fuel cell creates a significant current that is sustained for a period of time and can be repeated. A paper-based microbial fuel cell also has a fast response time. These results mean that it could be possible for a set of paper-based microbial fuel cells to create a power density capable of powering small, low power circuits when used in series or parallel. In this paper, we discuss the fabrication and experimental results of our paper-based microbial fuel cell. Also there will be a discussion of how paper-based microbial fuels cells compare to the traditional microbial fuel cells and how they could be used in the future.

The above referenced paper has been removed from publication. April 22, 2015. Copyright© 2015 by ASME

Reason: This paper was removed as a dual publication. Please see https://asmedigitalcollection.asme.org/ICEF/proceedings/ICEF2012/55096/83/238117. October 2, 2020. Copyright © 2020 by ASME

Second Law analysis or exergy analysis is a useful instrument to find ways to improve the efficiency of energy utilization. The method presents the magnitude and locations of true energy losses in an energy system. The pulp and paper industries have a big potential for increasing the energy efficiencies. An integration of a gas turbine with an existing steam turbine plant is one possible way to increase the energy efficiency and the power production. The cogeneration plant analysed in this paper is a hybrid combined plant in which two types of fuels are used. The exhaust gas from a combined cycle gas turbine via a waste heat recovery steam generator (HRSG) is used as preheated combustion air in a supplementary fired steam boiler. Saturated steam from the HRSG is assumed to be superheated in a boiler in which sludge, bark and other types of biomass are being used as fuels. To reduce the waste of energy, a flue gas driven fuel dryer is connected to evaporate some of the moisture in these biomass fuels. The study shows the effect of using a combined cycle instead of a simple steam cycle and the effect of using a fuel dryer. Among the configurations investigated, a plant with both a gas turbine and a fuel dryer yields the highest exergy efficiency and total efficiency. However, the net power efficiency is higher for a plant without a fuel dryer than for one with a fuel dryer.

Late in the summer of 1967 Southland Paper Mills, Inc. placed in operation a 52,000-kw combined cycle power plant. The plant utilizes two 13,550-kw gas turbines and one 25,000-kw single automatic extraction condensing steam turbine. The power plant furnishes the total power requirements for their new Sheldon mill. This paper presents background data on the mill and describes the power plant in some detail. Flow diagrams are presented and reviewed. Features of the generating equipment and the steam generators are described. Switchgear and load coordination is discussed. The operation and reliability of the plant to date are summarized and the combined cycle in terms of paper mill requirements is evaluated.Copyright © 1969 by ASME

This erratum corrects errors that appeared in the paper “A Simple Method for the Prediction of Wall Temperatures in Gas Turbines”, which was published in Proceedings of the ASME 1978 International Gas Turbine Conference and Products Show, Volume 1A: General, V01AT01A090, April 1978, 78-GT-90, doi: 10.1115/78-GT-90. This paper was originally published in 1978. There were numerous equation errors due to the typesetting limitations which have been corrected. The references have also been updated to contain additional information. Reference 12 is a duplicate of reference 10 and has also been removed.

The gas turbine or Brayton cycle offers many advantages over a conventional power plant, especially when installed in a cogeneration mode. These advantages include physically compact packages, high reliability, improved system economics and full operating flexibility to meet variable electrical/steam demand. Until recently, the primary disadvantage of the gas turbine cycle has been that internal burning of dirty fuels caused unacceptable erosion and corrosion of turbine blading. In the simple cycle gas turbine modified for indirect heating, the compressor discharge air passes through the tube side of a heat exchanger before passing on to the turbine. Heat is transferred to the air via the combustion products of alternative fuels passing through the shell side of the heat exchanger. This paper discusses the potential of the indirectly heated gas turbine burning wood in a cogeneration configuration with a back-pressure steam turbine.Copyright © 1980 by ASME

Inspired by human motor control theory, stiffness control is highly effective in manipulation and human-interactive tasks. The implementation of stiffness control in robotic systems, however, has largely been limited to closed-loop control, and suffers from multiple issues such as limited frequency range, potential instability, and lack of contribution to energy efficiency. Variable-stiffness actuator represents a better solution, but the current designs are complex, heavy, and bulky. The approach in this paper seeks to address these issues by using pneumatic actuator as a variable series elastic actuator (VSEA), leveraging the compressibility of the working fluid. In this work, a pneumatic actuator is modeled as an elastic element with controllable stiffness and equilibrium point, both of which are functions of air masses in the two chambers. As such, for the implementation of stiffness control in a robotic system, the desired stiffness/equilibrium point can be converted to the desired chamber air masses, and a predictive pressure control approach is developed to control the timing of valve switching to obtain the desired air mass while minimizing control action. Experimental results showed that the new approach in this paper requires less expensive hardware (on–off valve instead of proportional valve), causes less control action in implementation, and provides good control performance by leveraging the inherent dynamics of the actuator.

This paper reports the design, development, and initial evaluation of a robotic laparoscopic clipping tool for single manipulator wound closure and anastomosis (tubular reconnection). The tool deploys biodegradable clips and clasps with the goal of (i) integrating grasping and suturing into a single device for single hand or manipulator use, (ii) applying the equivalent of interrupted sutures without the need of managing suture thread, and (iii) allowing for full six degrees-of-freedom (DOFs) laparoscopic control when mounted on a robot arm. The specifications, workflow, and detailed design of the robotic laparoscopic tool and injection molded bio-absorbable T shaped clip and locking clasp are reported. The clipping tool integrates forceps to grab and stabilize tissue and a clip and clasp applier to approximate and fixate the tissue. A curved needle is advanced on a circular needle path and picks up and drags clips through tissue. The clip is then tightened through the tissue and a clasp is clamped around the clip, before the clip is released from the needle. Results of several bench test runs of the tool show: (a) repeatable circular needle drive, (b) successful pick-up and deployment of clips, (c) successful shear of the clip to release the clip from the needle, and (d) closure of clasp on clip with an average of 2.0 N holding force. These data indicate that the robotic laparoscopic clipping tool could be used for laparoscopic wound closure and anastomosis.

This study reports our experience of developing a series of biomedical engineering (BME) courses having active and experiential learning components in an interdisciplinary learning environment. In the first course, BME465: biomechanics, students were immersed in a simulation laboratory setting involving mannequins that are currently used for teaching in the School of Nursing. Each team identified possible technological challenges directly related to the biomechanics of the mannequin and presented an improvement overcoming the challenge. This approach of exposing engineering students to a problem in a clinical learning environment enhanced the adaptive and experiential learning capabilities of the course. In the following semester, through BME448: medical devices, engineering students were partnered with nursing students and exposed to simulation scenarios and real-world clinical settings. They were required to identify three unmet needs in the real-world clinical settings and propose a viable engineering solution. This approach helped BME students to understand and employ real-world applications of engineering principles in problem solving while being exposed to an interdisciplinary collaborative environment. A final step was for engineering students to execute their proposed solution from either BME465 or BME448 courses by undertaking it as their capstone senior design project (ENGR401-402). Overall, the inclusion of clinical immersions in interdisciplinary teams in a series of courses not only allowed the integration of active and experiential learning in continuity but also offered engineers more practice of their profession, adaptive expertise, and an understanding of roles and expertise of other professionals involved in enhancement of healthcare and patient safety.

Conversion of citrus processing waste (CPW) generated during juice production into value added co-products is an important aspect of the juice industry as it offers a solution to waste disposal issues. Currently the practice of drying citrus waste to produce citrus pulp pellets (CPP) for use as cattle feed is profitable. However, until the recent rise in value, CPP value was marginal and often did not meet production costs. Another concern has been volatile organic emissions during CPP production. Only one third of the residual peel oil present in citrus waste is recovered during CPP production with most being vented to the atmosphere during drying and is a growing environmental concern. Improvements in limonene recovery and development of alternative value added co-products obtained from CPW could add substantial value to the citrus crop. For current CPP production, the energy required to dry CPW is the major cost involved and approximately 25 lb of limonene are obtained per ton of CPP produced. Since limonene is recovered during evaporation/concentration of pressed peel juice using a waste heat evaporator, little additional cost is associated with limonene recovery. The concentrated citrus molasses produced may be added back to the press cake or fermented to make ethanol, but only contains a third of the sugars in CPW that are fermentable by conventional yeast. While utilizing the entire CPW stream for ethanol using hydrolysis and fermentation is more involved, three times the amount of ethanol can be obtained compared to using press liquor alone. Most of the limonene must be removed as it inhibits fermentation. In the process developed 85–95% of the limonene contained in CPW can be removed and recovered by steam stripping. This greatly reduces concerns associated with the release of volatile organic compounds (VOCs) during processing of CPW and the limonene recovered has a value equal or greater than stripping costs. Using a mixture of enzymes and yeast, the CPW is then hydrolyzed and fermented simultaneously to produce ethanol followed by distillation to remove and recover the ethanol. Enzyme costs to hydrolyze and liquefy CPW have been reduced to less than a dollar per gallon of ethanol produced, and the economics for distillation are still being optimized. The distillation residues contain half the solids of raw citrus waste that can still be utilized as a CPP product. Other uses for the residues such as incorporation of the pectic materials into building product and paper additives, and ion exchange materials for wastewater remediation are also in development. Paper published with permission.

This paper describes the resin treatment system developed by Bucher Alimentech NZ Ltd. (BAN) for the treatment of Citrus Products containing pulp and cloud. These products can be pure juices, core or pulp washes, or peel extracts and comminutes. The system does not use filtration membranes to first clarify the feed stream, instead a pulp reduced stream containing cloud is treated through the resin beds. Processes including debittering, colour adjustment, and ratio adjustment are described. Benefits are defined. Paper published with permission.

Creating highly articulated miniature structures requires assembling a large number of small parts. This is a very challenging task and increases cost of mechanical assemblies. Insert molding presents the possibility of creating a highly articulated structure in a single molding step. This can be accomplished by placing multiple metallic bearings in the mold and injecting plastic on top of them. In theory, this idea can generate a multi degree of freedom structures in just one processing step without requiring any post molding assembly operations. However, the polymer material has a tendency to shrink on top of the metal bearings and hence jam the joints. Hence, until now insert molding has not been used to create articulated structures. This paper presents a theoretical model for estimating the extent of joint jamming that occurs due to the shrinkage of the polymer on top of the metal bearings. The level of joint jamming is seen as the effective torque needed to overcome the friction in the revolute joints formed by insert molding. We then use this model to select the optimum design parameters which can be used to fabricate functional, highly articulating assemblies while meeting manufacturing constraints. Our analysis shows that the strength of weld-lines formed during the in-mold assembly process play a significant role in determining the minimum joint dimensions necessary for fabricating functional revolute joints. We have used the models and methods described in this paper to successfully fabricate the structure for a minimally invasive medical robot prototype with potential applications in neurosurgery. To the best of our knowledge, this is the first demonstration of building an articulated structure with multiple degrees of freedom using insert molding.

Joint loading is a recently developed mechanical modality, which potentially provides a therapeutic regimen to activate bone formation and prevent degradation of joint tissues. To our knowledge, however, few joint loading devices are available for clinical or point-of-care applications. Using a voice-coil actuator, we developed an electromechanical loading system appropriate for human studies and preclinical trials that should prove both safe and effective. Two specific tasks for this loading system were development of loading conditions (magnitude and frequency) suitable for humans, and provision of a convenient and portable joint loading apparatus. Desktop devices have been previously designed to evaluate the effects of various loading conditions using small and large animals. However, a portable knee loading device is more desirable from a usability point of view. In this paper, we present such a device that is designed to be portable, providing a compact, user-friendly loader. The portable device was employed to evaluate its capabilities using a human knee model. The portable device was characterized for force-pulse width modulation duty cycle and loading frequency properties. The results demonstrate that the device is capable of producing the necessary magnitude of forces at appropriate frequencies to promote the stimulation of bone growth and which can be used in clinical studies for further evaluations.

Southern Gardens Citrus and the Florida Department of Environmental Protection (FDEP), in a cooperative effort at the Clewiston citrus processing facility, reduced SO2 emissions by 80% and particulate matter emissions by 73%. This project also reduced costly diesel fuel use by 25%, increased citrus pulp feed mill operation efficiency, and saved the company more than $4 million a year. Paper published with permission.

This paper presents the effect of indium (In) content on the melting temperature, wettabililty, dross formation, and oxidation characteristics of the Sn-2Ag-3Bi-xIn alloy. The melting temperature of the Sn-2Ag-3Bi-xIn alloy (2 ≤ x ≤ 6) was lower than 473 K. The melting range between the solidus and liquidus temperatures was approximately 20 K, irrespective of the indium content. As the indium content increased, the wetting time increased slightly and the maximum wetting force remained to be mostly constant. The dross formation decreased to approximately 50% when adding 1In to Sn-2Ag-3Bi, and no dross formation was observed in the case of Sn-2Ag-3Bi-xIn alloy (x ≥ 1.5) at 523 K for 180 min. Upon approaching the inside of the oxidized solder of the Sn-2Ag-3Bi-1.5In alloy from the surface, the O and In contents decreased and the Sn content increased based on depth profiling analysis using Auger electron spectroscopy (AES). The mechanism for restraining dross (Sn oxidation) of Sn-2Ag-3Bi alloy with addition of indium may be due to surface segregation of indium. This is due to the lower formation energy of indium oxide than those of Sn oxidation.

Margarine as a raw material has a multiple uses in the production of bio-organic materials such as refined oil and butter. It passes through many industrial stages before beginning the process of refining and packaging it to the consumer. One of these important stages is the melting process, which wastes an immense amount of thermal power. The large rate of thermal power consumption occurs due to the huge reservoirs in which the margarine is stored (500 m3–1500 m3 Savola International Company-Suez Gulf region-Egypt). With drawing margarine from the reservoirs is a cost and time intensive process due to the solid state of margarine at environmental temperatures. Dry saturated steam is passed through the heat exchanger pipes inside the reservoir to melt the required amount of margarine. In some cases, this process can take up to 8 h in the summer and 12 h in the winter, which can be amplified by the loss of heat energy from the reservoir throughout the day, especially during the night periods. Moreover, steam boilers that use heavy fuel or natural gas can cause serious environmental damage as a result of emissions, such as the carbon oxide and nitrous oxide compounds. In contrast, solar energy is one of the cleanest and environmentally friendly renewable energies and should be invested as an alternative heat source for the melting process of margarine. As mentioned before, the melting of margarine is considered a heating process that consumes a huge amount of thermal energy. Therefore, solar thermal power can play a vital role in the process of melting margarine. Generally, temperature requirements of solar industrial heat applications range from 60 °C to 260 °C. Cylindrical PTC systems look very promising for delivering industrial heating process applications in the range of 95 °C–350 °C delivery temperature [1]. For solar thermal applications, the operating design conditions of solar collectors should be well above the desired operating conditions of the application to ensure stability of the operation. Therefore, flat plate collectors and evacuated tube collectors are eliminated from this study due to the previous reason and its lower efficiencies compared against the PTC [2]. This is why medium to medium–high temperature solar collectors are used [3,4]. Most of the production processes of the food industry such as milk products, vegetable, meat, fruits, and beer are run at temperatures below or near 100–130 °C. In addition, many cleaning processes such as pasteurizing, sterilizing, drying, hydrolyzing, distillation, washing, polymerization, and cooking processes are conducted under thermal applications [5,6]. Thus, switching to a renewable energy source, such as solar energy, can result in cost savings as well as decrease the negative impacts the production process has on the environment. The production process of margarine requires a large amount of heat in which solar thermal power is a viable and more cost effective source of energy. The problem originally emerged when Savola's company officials (Savola International Company in Margarine industrial Suez Gulf region-Egypt) decided to optimize the time, energy, and cost of the production process. They summarized their problems into the following points: The process of margarine melts takes more than 12 h to obtain 100–200 m3 of melted margarine per day. Which costs the equivalent amount of 476,120 m3 per day of natural gas (100,000 $/month). Reduction of CO2, NO2, and CO emissions is a must according to environmental laws. After reviewing the configuration of their heating process, using solar thermal power as a clean energy alternative seemed to be the most viable solution. Egypt has a great potential for solar energy. It is calculated that an amount of 6–7 kW h/m2/day of global radiation is in the Suez Gulf region-Egypt [8]. Therefore, it is very promising to utilize this vast amount of untapped solar energy in this industrial heating process. The aim of this research is to present a feasibility study, assessing the impact of using solar thermal power as an alternative source of energy in the margarine melting process. In this study, solar PTC is used instead of a conventional steam boiler. Water–steam and/or Therminol-VP1 [7] HTO are utilized through the PTC representing two different configurations. The data results of the conventional configuration (config1) are compared with the PTC–water steam configuration (config2) and PTC–Therminol configuration (config3) according to the hourly cost parameter ($/h). The study plan is organized as follows: The process configurations for the proposed systems are performed and the design limits are investigated. The mathematical model that represents the proposed systems is constructed. Three cases are compared (solar direct vapor generation (two configurations) was conventional configuration). Practical and analytical solutions for the process problems are studied and executed. solar desalination system (SDS) software package (a part of renewable energy desalination system (REDS) that were developed by the authors) was used to model all the system units [8–11]. 2. Margarine Melting Heating Process 2.1. The Process Problems. The problem began when Savola's-Egypt officials decided to evaluate the productive performance of their company. In their current configuration, a steam boiler running on fuels is used in the heating process. The company was faced with several problems identified as below. Wasted time, especially in the winter it requires melting about 100–300 m3 within approximately 12 h. This requires a significant amount of time before the canning process can begin. In addition, the steam boiler has to be operated during night hours to collect the melted margarine early in the morning before the canning process. It is noted that the fuel consumption is also very high, especially in the case of heavy fuel operations. As the average daily consumption reached 1 m3 or more, which is considered to be a high rate of consumption. The exhaust emissions resulting from the combustion inside the steam boiler today are unacceptable in the light of international regulations which intend to reduce global carbon emissions. Because of the temperature difference during the night especially in winter a large amount of thermal power gets wasted. This increases the operation time and the rate of fuel consumption. Thus, Savola's Egyptian officials contacted the authors to investigate and propose solutions to the existing inefficiencies, while at the same time decreasing the negative impact on the environment.

Computational modeling is very useful in biomechanics to simulate normal and pathologic joint function. It is also useful to determine the efficacies of various surgical procedures performed to treat joint pathologies and simulate their outcomes. Models can be used to estimate in situ measures such as contact pressure distributions that are difficult to acquire through experiments noninvasively. Currently, computational modeling is the only technique available to noninvasively evaluate in vivo joint contact mechanics [1]. However, most models make use of input parameters derived from various general sources such as literature, standards, or experiments and are, therefore, limited for patient-specific applications [2]. Joint injuries, whether ligaments or articular surface, are a significant problem and there is still a need for tools to effectively evaluate joint injuries and associated sequelae [3]. The ability to monitor the initiation and progression of joint instability after injury may aid in determining prognosis, leading to better treatment algorithms. In order to refine or develop treatments that are targeted toward individuals, it is important to focus on subject-specific models. Several modeling techniques exist to evaluate in vivo joint mechanics. The common techniques include image-based FEM [4–13], rigid body spring modeling/discrete element analysis (RBSM) [14–16], or SCM [17–19]. The models are either displacement driven or force driven. Generally, model geometries are acquired from modalities such as computed tomography (CT) [4–8,14,15,19] or MRI [9–11,17,18]. Kinematics are determined through external (surface markers) or internal (biplanar radiography) measures, while tendon forces are estimated from corresponding musculature electromyography (EMG) and cross-sectional area, and ground reaction forces are measured using force platforms [11,20]. These loads and displacement boundary conditions are input into the model to infer joint kinetics/kinematics and resulting surface and/or volumetric stresses and strains. FEM is the most common and accurate method to determine stresses [11,20,21]. However, depending on the complexity of the problem, the process of developing the mesh can be laborious and obtaining a converged solution can be computationally intensive [22], which limits its clinical applicability. Depending on the type of problem (for instance, deformable versus rigid), more simplified analyses can be performed based on relevant assumptions to determine appropriate solutions. This is the basis of RBSM and SCM techniques. Using these methods, joint mechanics can be evaluated in a computationally efficient manner compared to FEM [23], which makes them relevant for clinical applications. The underlying question is whether these methods are competent to provide data that are sufficiently accurate for the intended application. The ability to accurately determine joint mechanics has wide clinical implications, especially in complex joints such as the wrist. It may be possible to sufficiently evaluate changes in joint mechanics as a result of injury or surgical intervention from surface contact mechanics data alone. This can be achieved through the SCM technique, without the need for a complex volumetric analysis [24]. However, the SCM technique has not been extensively used for orthopedic applications. Computational modeling has been extensively applied to the lower extremity to evaluate in vivo joint mechanics [4–11,18]. In the wrist, studies have evaluated in vivo joint mechanics during functional activities [12,14,16,17] and have also simulated the effects of some carpal fractures and limited fusions [13,15,19]. Scapholunate (SL) ligament injury is a commonly occurring wrist ligament injury that can lead to SL joint instability and progressive degenerative changes [25–28]. Prior modeling work on the in vivo effects of SL ligament injury or surgical repair appears to be limited [29,30]. Hence, we investigated differences in radiocarpal in vivo joint mechanics obtained from SCM for normal wrists, after SL ligament injury, and after surgical repair to results from the FEM “gold standard.” We did not intend to make comparisons between the normal, injured, and postoperative states. Our goal was to show that contact outcomes obtained from SCM would be comparable to those obtained from a similar FEM analysis regardless of wrist state and to demonstrate the feasibility and applicability of the SCM technique.

One's ability to exert controlled forces on the environment, such as when manipulating fragile objects, is very important in everyday life. This suggests that force regulation is a necessary component of motor control. In robotics, an effective way to implement force control is by imposing a low contact impedance with critical damping, and using admittance control to regulate force output [1,2]. Human limbs can be modeled as second order mechanical systems, under the assumption that tendons are much stiffer than muscle fibers. The mechanical properties of muscle fibers alone render the implementation of the aforementioned direct force control strategy as not efficient. Several studies have demonstrated that the exertion of force onto the environment results in an increase in muscle stiffness [3–5] and a reduction of muscle damping to under critical values [6,7]. Modeling tendons and contractile elements independently requires higher than second order muscle-tendon models [8]. The presence of a tendon elastic element favors an oscillatory response to external disturbances that normally needs to be eliminated [9]. We demonstrated that a higher order model always exhibits an oscillatory free response and cannot be critically dampened for mechanical parameters included within the normal physiological range. This requires the force controller implemented by the central nervous system (CNS) to employ active feedback and feed-forward regulation. We propose that oscillations, whether part of an external disturbance or of the system's response, can be actively compensated for by the CNS with a position control approach, as long as a predictive model of the perturbation, and an internal model of the system's biomechanics are available. This model of control is in agreement with findings previously published by our group that showed how the implementation of an internal feed-forward model trajectory can be part of a force-regulation strategy [10].

This study presents a methodology to determine thumb and index finger kinematics while utilizing a minimal set of markers. The motion capture of skin-surface markers presents inherent challenges for the accurate and comprehensive measurement of digit kinematics. As such, it is desirable to utilize robust methods for assessing digit kinematics with fewer markers. The approach presented in this study involved coordinate system alignment, locating joint centers of rotation, and a solution model to estimate three-dimensional (3-D) digit kinematics. The solution model for each digit was based on assumptions of rigid-body interactions, specific degrees of freedom (DOFs) at each located joint, and the aligned coordinate system definitions. Techniques of inverse kinematics and optimization were applied to calculate the 3-D position and orientation of digit segments during pinching between the thumb and index finger. The 3-D joint center locations were reliably fitted with mean coefficients of variation below 5%. A parameterized form of the solution model yielded feasible solutions that met specified tolerance and convergence criteria for over 85% of the test points. The solution results were intuitive to the pinching function. The thumb was measured to be rotated about the CMC joint to bring it into opposition to the index finger and larger rotational excursions (>10 deg) were observed in flexion/extension compared to abduction/adduction and axial rotation for all joints. While the solution model produced results similar to those computed from a full marker set, the model facilitated the usage of fewer markers, which inherently lessened the effects of passive motion error and reduced the post-experimental effort required for marker processing.

In this work, a semiactive electromagnetic vibration absorber has been developed based on a proposed electromagnetic stiffness adjustable spring model, which presents a new solution for adjusting stiffness in the field of vibration absorber devices. Simulation study on the electromagnetic spring has been performed to determine the structural parameter of the semiactive vibration absorber. An experimental rig is also built up to investigate its practical vibration control effectiveness. Firstly, the finite element model of the test bench is used to analyze its vibration characteristics. Then, the vibration reduction effect is predicted through the simulation analysis, from which the optimal control positions are found. Finally, the experimental studies are also conducted, and the results show that this semiactive electromagnetic vibration absorber has a frequency adjustment range from 21 Hz to 25 Hz, in which considerable vibration reduction from 5 dB to 10 dB can be achieved.

Muscle-driven simulations of human and animal motion are widely used to complement physical experiments for studying movement dynamics. Musculotendon models are an essential component of muscle-driven simulations, yet neither the computational speed nor the biological accuracy of the simulated forces has been adequately evaluated. Here we compare the speed and accuracy of three musculotendon models: two with an elastic tendon (an equilibrium model and a damped equilibrium model) and one with a rigid tendon. Our simulation benchmarks demonstrate that the equilibrium and damped equilibrium models produce similar force profiles but have different computational speeds. At low activation, the damped equilibrium model is 29 times faster than the equilibrium model when using an explicit integrator and 3 times faster when using an implicit integrator; at high activation, the two models have similar simulation speeds. In the special case of simulating a muscle with a short tendon, the rigid-tendon model produces forces that match those generated by the elastic-tendon models, but simulates 2–54 times faster when an explicit integrator is used and 6–31 times faster when an implicit integrator is used. The equilibrium, damped equilibrium, and rigid-tendon models reproduce forces generated by maximally-activated biological muscle with mean absolute errors less than 8.9%, 8.9%, and 20.9% of the maximum isometric muscle force, respectively. When compared to forces generated by submaximally-activated biological muscle, the forces produced by the equilibrium, damped equilibrium, and rigid-tendon models have mean absolute errors less than 16.2%, 16.4%, and 18.5%, respectively. To encourage further development of musculotendon models, we provide implementations of each of these models in OpenSim version 3.1 and benchmark data online, enabling others to reproduce our results and test their models of musculotendon dynamics.

The use of compliance chambers in mock circulatory loop construction is the predominant means of simulating arterial compliance. Utilizing mock circulatory loops as bench test methods for cardiac assist technologies necessitates that they must be capable of reproducing the circulatory conditions that would exist physiologically. Of particular interest is the ability to determine instantaneous compliance of the system, and the ability to change the compliance in real-time. This capability enables continuous battery testing of conditions without stopping the flow to change the compliance chamber settings, and the simulation of dynamic changes in arterial compliance. The method tested involves the use of a compliance chamber utilizing a circular natural latex rubber membrane separating the fluid and air portions of the device. Change in system compliance is affected by the airspace pressure, which creates more reaction force at the membrane to the fluid pressure. A pressure sensor in the fluid portion of the chamber and a displacement sensor monitoring membrane center deflection allow for real-time inputs to the control algorithm. A predefined numerical model correlates the displacement sensor data to the volume displacement of the membrane. The control algorithm involves a tuned π loop maintaining the volume distention of the membrane via regulation of the air space pressure. The proportional integral (PI) controller tuning was achieved by creating a computational model of the compliance chamber using Simulink™ Simscape® toolboxes. These toolboxes were used to construct a model of the hydraulic, mechanical, and pneumatic elements in the physical design. Parameter Estimation™ tools and Design Optimization™ methods were employed to determine unknown physical parameters in the system, and tune the process controller used to maintain the compliance setting. It was found that the resulting control architecture was capable of maintaining compliance along a pressure-volume curve and allowed for changes to the compliance set point curve without stopping the pulsatile flow.

The concern with Fitness-For-Service (FFS) assessment using stochastic analysis for aged pressure equipments with local metal loss has been growing for the last several years. The structural integrity assessment based on reliability helps to make a decision as to whether to run or repair the equipments with local metal loss. As for analysis of failure probability, it is important to clear which variables affect highly the structural integrity. The stochastic property of the influential parameter needs to be clarified. There has, however, been little study to analyze quantitatively the sensitivity of the parameters for the FFS assessment of the components with local metal loss. In this study, the effects of parameters on plastic collapse of the damaged component were evaluated utilizing parameter sensitivity study. Additionally, sensitivity indices for the component with several shapes of local metal loss were analyzed. It was found from the results that the corrosion rate has much influence on probability of failure. Finally, practical stochastic analysis procedure for the component with local metal loss was proposed. In the proposed procedure, the parameter which has consistently low sensitivity to limit state was used as constant value.

The importance of this development to the citrus industry need not be further discussed as all of you are well aware of financial advantage possible through pulp washing. Paper published with permission.

Processors of citrus fruit are faced with disposal of the pulp left over after juice is extracted from the fruit. Generally, the pulp is dried in steam or oil fired dryers and then sold as cattle feed. If disposal of the pulp is the prime factor of interest to the operator; shredding and hot air drying is sufficient. For more efficient removal of water from the pulp and the obtainment of other by-products, mainly citrus molasses and stripper oil, consideration should be given to the installation of presses and a molasses evaporator. Most authorities will agree that water can be evaporated more efficiently in a multiple effect evaporator than in a hot air dryer. Presses and an evaporator represent considerable investment, therefore the decision to install a Molasses Plant must be weighed carefully, balancing potential savings against the installed cost. Paper published with permission.

Bulk storage of dried citrus pulp at Plymouth was first considered because our customers, many of whom have been buying our pulp for 15 years, were adopting feeding systems which fitted bulk feeds, and because bag and bag dumping costs seemed to provide a source for sizeable savings. Paper published with permission.

The growing interest in citrus pulp, or frozen, stabilized juice sacs, stems from the rapid influx of high quality citrus juices and juice added beverages into the market. Juice sacs have been recovered for many years and it has not been until the past few years that this practice evolved into a sophisticated technology. Paper published with permission.

In most large citrus processing plants world-wide, the peel is made into cattle feed. The peel is shredded, mixed with lime, allowed to react, and pressed. The liquid from the pressing is evaporated and recycled into the peel or sold as molasses. The press cake is dried in single pass, direct fired rotary dryers with co-current flow of heating gasses and product. Paper published with permission.

One of the most perplexing problems that confronts the designer of citrus processing machinery and equipment is that of corrosion resistance. Citrus waste product, pulp, and juice have a citric acid content of around 2.7% by weight which will quickly destroy paint or lacquer finishes and will rapidly corrode carbon or low alloy steels. Only the highly alloyed chromium nickel steels, monel, inconel, pure nickel, some of the bronzes, tin and copper can withstand the corrosive attack of citrus juice and pulp. Paper published with permission.

Dried citrus pulp is an important by-product of the citrus processing industry. It is a bulky, granular, carbohydrate concentrate livestock feed produced by drying the peel, seed, and rag refuse of citrus fruit. Approximately 324,159 tons of citrus pulp were produced in 1964–65 (2). This amount will probably increase by more than 60 percent during the next 10 years, since the orange crop is expected to increase from the 1964–65 estimate of 83,000,000 boxes to 183,000,000 by 1975 with 80 percent of the oranges being processed (7). The 1975 grapefruit crop is expected to be 30,000,000 boxes with over one-half being processed. These increases in citrus production could mean that by 1975 over 650,000 tons of dried pulp would be produced in the State. Paper published with permission.

Most of you have probably noticed the new addition to the Kraft Citrus Products Division Plant here in Lakeland. This is their new sectionizing plant for the preparation of fruit salad, which has only been in operation for a few weeks. Paper published with permission.

The UK Small Modular Reactor (UKSMR) programme has been established to develop an SMR for the UK energy market. Developing an SMR is a multi-disciplinary technical challenge, involving nuclear physics, electrical, mechanical, design, management, safety, testing to name but a few. In 2016 Upadhyay & Jain performed a literature review on modularity in Nuclear Power. They concluded that although modularisation has been utilised in nuclear to reduce costs, more work needs to be done to “create effective modules”. Hohmann et al also concluded the same for defining modules in the chemical process plant industry. The aim of this paper is to further define modules with a particular focus on an SMR for the UK market, the UKSMR. The methods highlighted may be relevant and applied to other international SMR designs or other types of plant. An overview and examination of modularisation work in nuclear to date is provided. The different configurations are defined for the Nuclear Steam Supply System (NSSS) in primary circuits and then for Balance of Plant (BOP) modules. A top level design process has been defined to aid in the understanding of design choices for current reactors and to further assist designing balance of plant modules. The paper then highlights areas for additional research that may further support module design and definition.

Well-designed tissue engineering scaffolds are needed for effective healing by regulating cell behavior such as cell attachment, proliferation and differentiation. Scaffolds should not only exhibit biocompatibility, interconnected porosity and strength but should provide hydrophilic surface where cell adheres in-vitro and in-vivo. The aim of this study is the fabrication and analysis of porous and surface functionalized biocompatible scaffolds for bone tissue engineering. In the first part of the study, we produce porous polycaprolactone (PCL)-nano-hydroxyapatite (nHA) scaffolds using earlier proposed non-solvent induced phased separation (NIPS) and use initiated chemical vapor deposition (iCVD) for coating these scaffolds with Poly (hydroxyethylmethacrylate-co-ethyleneglycol dimethacrylate) (p(HEMA-co-EGDMA)) polymer. The goal is to increase hydrophilicity of scaffolds using iCVD coating on scaffolds fabricated using NIPS and to demonstrate its feasibility for further functionalization such as GF immobilization and release. In the second part of the paper we develop an initial analysis framework suitable for the characterization of BMP-2 growth factor (GF) release of both coated and uncoated bone scaffolds using a Finite Element Analysis taking into account diffusion and possible chemical reaction. In the experimental part, surface characterization via Fourier-transform infrared spectroscopy (FTIR) confirmed a successful conformal coating and contact angle measurements demonstrate that desired hydrophilic surface was obtained after iCVD coating. Therefore, the first part of the study demonstrated that surface modified PCL-nHA scaffolds with p(HEMA-co-EGDMA) hydrogel exhibited increased hydrophilicity that should allow for augmented compatibility with cell media by enhancing cell attachment, proliferation and differentiation in vitro. In the computational part of the paper, as a second parametric study, the effects of a possible iCVD coating were analyzed by modifying the biomaterial matrix domain and tuning its diffusion coefficient where the reaction and release is expected to occur. The diffusion coefficient of coating material was set to two different values chosen lower than the tissue domain. Simulation results for the addition of a coating layer with a larger diffusion coefficient value resulted in a decreased BMP-2 diffusion accompanied by a parallel decrease in BMP-2 concentration in the tissue with respect to time and across the domain. Overall, it is concluded that initial parametric studies showed that the release and concentration profile could be tuned based on morphological and material properties of the scaffold. Also, coating biomaterial matrix via iCVD acquired directional/anisotropic diffusion in the model domain via one-sided coating of the scaffold matrix. Formal optimization studies could be integrated to the proposed simulation model to design functional scaffolds coated with iCVD for controlled and directional growth factor release.

This paper discusses the design and conceptualization of a novel robotic mechanism to clean the trench drains. It describes a different approach for drain cleaning with lesser human intervention and more safety to personnel involved. The robot is designed and built to be 4 inches in width and operate entirely within the limited space inside the drain. To achieve a wholesome cleaning process, the entire robot is modular in design and consists of a drive system, a suction tube and a cutting arm assembly with metal brushes installed onto it. The bidirectional drive system enables the robot to move through drain segments repeatedly for optimal performance. The purpose of the cutting arm assembly is to aid the removal of dirt from the drain. In order to improve the robot performance, two prototypes were designed and built. The overall design and modularity of both robot prototypes will be discussed in detail in the paper.