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Full-Text Articles in Mechanical Engineering

Direct Observation Of The Formation And Stabilization Of Metallic Nanoparticles On Carbon Supports, Zhennan Huang, Yonggang Yao, Zhenqian Pang, Yifei Yuan, Tangyuan Li, Kun He, Xiaobing Hu, Jian Cheng, Wentao Yao Dec 2020

Direct Observation Of The Formation And Stabilization Of Metallic Nanoparticles On Carbon Supports, Zhennan Huang, Yonggang Yao, Zhenqian Pang, Yifei Yuan, Tangyuan Li, Kun He, Xiaobing Hu, Jian Cheng, Wentao Yao

Michigan Tech Publications

Direct formation of ultra-small nanoparticles on carbon supports by rapid high temperature synthesis method offers new opportunities for scalable nanomanufacturing and the synthesis of stable multi-elemental nanoparticles. However, the underlying mechanisms affecting the dispersion and stability of nanoparticles on the supports during high temperature processing remain enigmatic. In this work, we report the observation of metallic nanoparticles formation and stabilization on carbon supports through in situ Joule heating method. We find that the formation of metallic nanoparticles is associated with the simultaneous phase transition of amorphous carbon to a highly defective turbostratic graphite (T-graphite). Molecular dynamic (MD) simulations suggest that …


Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar Dec 2020

Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar

Michigan Tech Publications

We study a Multiple Depot Heterogeneous Traveling Salesman Problem (MDHTSP) where the cost of the traveling between any two targets depends on the type of the vehicle. The travel costs are assumed to be symmetric, satisfy the triangle inequality, and are monotonic, i.e., the travel costs between any two targets monotonically increases with the index of the vehicles. Exploiting the monotonic structure of the travel costs, we present a 2-approximation algorithm based on the primal-dual method.


Radio Frequency Emissions From Dark-Matter-Candidate Magnetized Quark Nuggets Interacting With Matter, J. Pace Vandevender, C. Jerald Buchenauer, Chunpei Cai, Aaron P. Vandevender, Benjamin A. Ulmen Dec 2020

Radio Frequency Emissions From Dark-Matter-Candidate Magnetized Quark Nuggets Interacting With Matter, J. Pace Vandevender, C. Jerald Buchenauer, Chunpei Cai, Aaron P. Vandevender, Benjamin A. Ulmen

Michigan Tech Publications

Quark nuggets are theoretical objects composed of approximately equal numbers of up, down, and strange quarks. They are also called strangelets, nuclearites, AQNs, slets, Macros, and MQNs. Quark nuggets are a candidate for dark matter, which has been a mystery for decades despite constituting ~ 85% of the universe’s mass. Most previous models of quark nuggets have assumed no intrinsic magnetic field; however, Tatsumi found that quark nuggets may exist in magnetars as a ferromagnetic liquid with a magnetic field BS = 1012±1 T. We apply that result to quark nuggets, a dark-matter candidate consistent with the Standard Model, and …


A Low-Cost Secure Iot Mechanism For Monitoring And Controlling Polygeneration Microgrids, Josué Martínez-Martínez, Diego Aponte-Roa, Idalides Vergara-Laurens, Wayne Weaver Dec 2020

A Low-Cost Secure Iot Mechanism For Monitoring And Controlling Polygeneration Microgrids, Josué Martínez-Martínez, Diego Aponte-Roa, Idalides Vergara-Laurens, Wayne Weaver

Michigan Tech Publications

The use of Internet-connected devices at homes has increased to monitor energy consumption. Furthermore, renewable energy sources have also increased, reducing electricity bills. However, the high cost of the equipment limits the use of these technologies. This paper presents a low-cost secured-distributed Internet of Things (IoT) system to monitor and control devices connected in a polygeneration microgrid, as a combined power system for local loads with renewable sources. The proposed mechanism includes a Wireless Sensor Actuator Networked Control System that links network nodes using the IEEE 802.15.4 standard. The Internet communication enables the monitor and control of devices using a …


The Economics Of Classroom 3-D Printing Of Open-Source Digital Designs Of Learning Aids, Nicole Gallup, Joshua M. Pearce Nov 2020

The Economics Of Classroom 3-D Printing Of Open-Source Digital Designs Of Learning Aids, Nicole Gallup, Joshua M. Pearce

Michigan Tech Publications

While schools struggle financially, capital for purchasing physical learning aids is often cut. To determine if costs could be reduced for learning aids, this study analyzed classroom-based distributed digital manufacturing using 3-D printing of open-source learning aid designs. Learning aid designs are analyzed in detail for their economic viability considering printing and assembly costs with purchased components and compared to equivalent or inferior commercial products available on Amazon. The results show current open-source 3-D printers are capable of manufacturing useful learning aids and that doing so provides high economic savings in the classroom. Overall, the average learning aid would save …


Rf Studies Of Soot And Ammonia Loadings On A Combined Particulate Filter And Scr Catalyst, Shreyans Sethia, David Kubinski, Hans Nerlich, Jeffrey Naber Nov 2020

Rf Studies Of Soot And Ammonia Loadings On A Combined Particulate Filter And Scr Catalyst, Shreyans Sethia, David Kubinski, Hans Nerlich, Jeffrey Naber

Michigan Tech Publications

Modern diesels employ a particulate filter (DPF) to reduce soot emissions. Additionally, the selective catalytic reduction (SCR) of NOx by NH3 stored on the SCR catalyst reduces NOx emissions. In some vehicles the functions of these aftertreatment components are combined in the SDPF, a DPF having a SCR washcoat. The RF resonant method has been shown to be an alternative tool for measuring the DPF's soot loading and the SCR's NH3 loading. For both applications, the transmitted electromagnetic signal between antennae placed on either side of the catalyst change with loading. Here we report the influence of the RF signal …


Effect Of Geometry And Fluid Viscosity On Dynamics Of Fluid-Filled Cracks: Insights From Analog Experimental Observations, Haitao Cao, Ezequiel F. Medici, Gregory P. Waite, Roohollah Askari Nov 2020

Effect Of Geometry And Fluid Viscosity On Dynamics Of Fluid-Filled Cracks: Insights From Analog Experimental Observations, Haitao Cao, Ezequiel F. Medici, Gregory P. Waite, Roohollah Askari

Michigan Tech Publications

Fluid-filled volumes in geological systems can change the local stress field in the host rock and may induce brittle deformation as well as crack propagation. Although the mechanisms relating fluid pressure perturbations and seismicity have been widely studied, the fluid-solid interaction inside the crack of a host rock is still not well understood. An analog experimental model of fluid intrusion in cracks between planar layers has been developed to study stress conditions at the margins and tips. A combined high-speed shadowgraph and a photoelasticity imaging system is used to visualize the fluid dynamics and induced stresses on the solid matrix. …


Towards Real-Time Reinforcement Learning Control Of A Wave Energy Converter, Enrico Anderlini, Salman Husain, Gordon Parker, Mohammad Abusara, Giles Thomas Nov 2020

Towards Real-Time Reinforcement Learning Control Of A Wave Energy Converter, Enrico Anderlini, Salman Husain, Gordon Parker, Mohammad Abusara, Giles Thomas

Michigan Tech Publications

The levellised cost of energy of wave energy converters (WECs) is not competitive with fossil fuel-powered stations yet. To improve the feasibility of wave energy, it is necessary to develop effective control strategies that maximise energy absorption in mild sea states, whilst limiting motions in high waves. Due to their model-based nature, state-of-the-art control schemes struggle to deal with model uncertainties, adapt to changes in the system dynamics with time, and provide real-time centralised control for large arrays of WECs. Here, an alternative solution is introduced to address these challenges, applying deep reinforcement learning (DRL) to the control of WECs …


Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra G. Tanikella, Joshua M. Pearce Oct 2020

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra G. Tanikella, Joshua M. Pearce

Michigan Tech Publications

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met …


A Control System For A Constrained Two-Body Wave Energy Converter, Shangyan Zou, Ossama Abdelkhalik Sep 2020

A Control System For A Constrained Two-Body Wave Energy Converter, Shangyan Zou, Ossama Abdelkhalik

Michigan Tech Publications

Wave energy can be used to power oceano-graphic buoys. A new switching control strategy is developed in this paper for a two-body heaving wave energy converter that is composed of a floating cylinder and two rigidly connected submerged hemispheres. This control strategy is designed to prevent excessive displacement of the floating buoy that may occur due to the actuator force. This control strategy switches the control between a multi-resonant controller and a nonlinear damping controller, depending on the state of the system, to account for displacement constraints. This control strategy is developed using a one-degree-of-freedom dynamic model for the relative …


Open-Source Grinding Machine For Compression Screw Manufacturing, Jacob Franz, Joshua M. Pearce Sep 2020

Open-Source Grinding Machine For Compression Screw Manufacturing, Jacob Franz, Joshua M. Pearce

Michigan Tech Publications

Some of the most promising distributed recycling and additive manufacturing (DRAM) technical systems use fused particle fabrication (FPF) or fused granular fabrication (FGF), where compression screws force post-consumer waste plastic through a heated nozzle for direct 3D printing. To assist the technical evolution of these systems, this study provided the details of an invention for a low-cost, easily replicable open-source grinding machine for compression screw manufacturing. The system itself can be largely fabricated using FPF/FGF following the self-replicating rapid prototyper (RepRap) methodology. This grinding machine can be made from a cordless cut-off grinder and < $155 in parts. The new invention is demonstrated to be able to cut custom screws with variable (i) channel depths, (ii) screw diameters, (iii) screw lengths, (iv) pitches, (v) abrasive disk thicknesses, (vi) handedness of the screws, (vii) and materials (three types of steel tested: 1045 steel, 1144 steel, and 416 stainless steel). The results show that the device is more than capable of replicating commercial screws as well as providing makers with a much greater flexibility to make custom screws. This invention enables the DRAM toolchain to become even more self-sufficient, which assists the goals of the circular economy.


The Effect Of Adsorbed Volatile Organic Compounds On An Ultrathin Water Film Measurement, Shahab Bayani Ahangar, Chan Ho Jeong, Fei Long, Jeffrey S. Allen, Seong Hyuk Lee, Chang Kyoung Choi Aug 2020

The Effect Of Adsorbed Volatile Organic Compounds On An Ultrathin Water Film Measurement, Shahab Bayani Ahangar, Chan Ho Jeong, Fei Long, Jeffrey S. Allen, Seong Hyuk Lee, Chang Kyoung Choi

Michigan Tech Publications

Using surface plasmon resonance imaging (SPRi), we have recently shown for the first time the existence of a monolayer water film between droplets during dropwise condensation. This study examines the effect of adsorbed volatile organic compounds (VOCs) on the ultrathin film measurement using SPRi. Further, the work presents the proper surface-treatment process that enables measurements of the ultrathin water layer during high-speed imaging of dropwise condensation at 3000 frame per second. In this study, two methods were applied for cleaning the surface (gold-coated glass)-(1) standard cleaning procedure (SCP) using acetone, isopropyl alcohol, and deionized water and (2) SCP followed by …


Power Take-Off And Energy Storage System Static Modeling And Sizing For Direct Drive Wave Energy Converter To Support Ocean Sensing Applications, Xiang Zhou, Ossama Abdelkhalik, Wayne Weaver Jul 2020

Power Take-Off And Energy Storage System Static Modeling And Sizing For Direct Drive Wave Energy Converter To Support Ocean Sensing Applications, Xiang Zhou, Ossama Abdelkhalik, Wayne Weaver

Michigan Tech Publications

This paper addresses the sizing and design problem of a permanent magnet electrical machine power take-off system for a two-body wave energy converter, which is designed to support ocean sensing applications with sustained power. The design is based upon ground truth ocean data bi-spectrums (swell and wind waves) from Martha’s Vineyard Coastal Observatory in the year 2015. According to the ground truth ocean data, the paper presents the optimal harvesting power time series of the whole year. The electrical machine and energy storage static modeling are introduced in the paper. The paper uses the ground truth ocean data in March …


Open-Source Digitally Replicable Lab-Grade Scales, Benjamin R. Hubbard, Joshua M. Pearce Jun 2020

Open-Source Digitally Replicable Lab-Grade Scales, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications

This study provides designs for a low-cost, easily replicable open-source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open-source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open-source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open-source scale was found to be repeatable within 0.05 g with multiple load cells, with even better precision (0.005 …


Investigation Of Deformation Induced Micro To Macro Scale Surface Roughness, Ayotunde Olayinka, William J. Emblom, Scott W. Wagner, Michael Khonsari, Ali Haghshenas Jun 2020

Investigation Of Deformation Induced Micro To Macro Scale Surface Roughness, Ayotunde Olayinka, William J. Emblom, Scott W. Wagner, Michael Khonsari, Ali Haghshenas

Michigan Tech Publications

In the present work the relationship between deformation and deformation induced surface roughness of 100 micron thick annealed AISI 304 stainless steel was investigated at the meso scale. This work is a continuation of the previous work by the authors where roughness values were determined at the apex of the bulge test samples at micro scale. The apex is believed to be the region of highest stress and strain in a typical bulge process in a circular die. The material was deformed using a biaxial bulge test through hydraulic fluid pressure. The strains on the workpieces were measured with respect …


Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce Jun 2020

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications

To assist firefighters and other first responders to use their existing equipment for respiration during the COVID-19 pandemic without using single-use, low-supply, masks, this study outlines an open source kit to convert a 3M-manufactured Scott Safety self-contained breathing apparatus (SCBA) into a powered air-purifying particulate respirator (PAPR). The open source PAPR can be fabricated with a low-cost 3-D printer and widely available components for less than $150, replacing commercial conversion kits saving 85% or full-fledged proprietary PAPRs saving over 90%. The parametric designs allow for adaptation to other core components and can be custom fit specifically to fire-fighter equipment, including …


Sparse And Random Sampling Techniques For High-Resolution, Full-Field, Bss-Based Structural Dynamics Identification From Video, Bridget Martinez, Andre Green, Moises Felipe Silva, David Mascareñas, Yongchao Yang Jun 2020

Sparse And Random Sampling Techniques For High-Resolution, Full-Field, Bss-Based Structural Dynamics Identification From Video, Bridget Martinez, Andre Green, Moises Felipe Silva, David Mascareñas, Yongchao Yang

Michigan Tech Publications

Video-based techniques for identification of structural dynamics have the advantage that they are very inexpensive to deploy compared to conventional accelerometer or strain gauge techniques. When structural dynamics from video is accomplished using full-field, high-resolution analysis techniques utilizing algorithms on the pixel time series such as principal components analysis and solutions to blind source separation the added benefit of high-resolution, full-field modal identification is achieved. An important property of video of vibrating structures is that it is particularly sparse. Typically video of vibrating structures has a dimensionality consisting of many thousands or even millions of pixels and hundreds to thousands …


Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met …


Chlorine Removal From U.S. Solid Waste Blends Through Torrefaction, Zhuo Xu, Josh W. Albrecht, Shreyas Kolapkar, Stas Zinchik, Ezra Bar Ziv May 2020

Chlorine Removal From U.S. Solid Waste Blends Through Torrefaction, Zhuo Xu, Josh W. Albrecht, Shreyas Kolapkar, Stas Zinchik, Ezra Bar Ziv

Michigan Tech Publications

The amount of solid waste generated annually is increasing around the world. Although the waste has a high calorific value, one major obstacle that may prevent it from becoming a feedstock for power applications is the existence of polyvinyl chloride (PVC), which causes corrosion and emission issues after combustion due to its high chlorine content. Torrefaction is known to release hydrochloric acid; thus, it has been applied in this study for the reduction of chlorine from potential waste feedstocks. Fiber-plastic (60-40%) waste blends, with different chlorine content levels, as well as PVC were used in the current study. Torrefaction was …


Energy Storage Power And Energy Sizing And Specification Using Hsspfc, Mehrzad M. Bijaieh, Wayne Weaver, Rush D. Robinett Iii Apr 2020

Energy Storage Power And Energy Sizing And Specification Using Hsspfc, Mehrzad M. Bijaieh, Wayne Weaver, Rush D. Robinett Iii

Michigan Tech Publications

The intermittent nature of renewable sources requires the integration of Energy Storage Systems (ESSs) with appropriate power and energy densities. One of the applications of Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) is to size ESSs for power and energy densities by employing them as sole actuators of Microgrid (MG) systems. This Article provides a comprehensive yet simplified example of utilization of HSSPFC to size ESSs of inverter-based three-phase MG systems under hierarchical control. Here, the distributed Hamiltonian controller is expanded for control of parallel ESSs and power sharing metrics are defined to distribute power between hybrid storage systems …


Electric Vehicle-Grid Integration With Voltage Regulation In Radial Distribution Networks, Chong Cao, Zhouquan Wu, Bo Chen Apr 2020

Electric Vehicle-Grid Integration With Voltage Regulation In Radial Distribution Networks, Chong Cao, Zhouquan Wu, Bo Chen

Michigan Tech Publications

In this paper, a vehicle-grid integration (VGI) control strategy for radial power distribution networks is presented. The control schemes are designed at both microgrid level and distribution level. At the VGI microgrid level, the available power capacity for electric vehicle (EV) charging is optimally allocated for charging electric vehicles to meet charging requirements. At the distribution grid level, a distributed voltage compensation algorithm is designed to recover voltage violation when it happens at a distribution node. The voltage compensation is achieved through a negotiation between the grid-level agent and VGI microgrid agents using the alternating direction method of multipliers. In …


Fracture Toughness Analysis Of Epoxy-Recycled Rubber-Based Composite Reinforced With Graphene Nanoplatelets For Structural Applications In Automotive And Aeronautics, Alaeddin Burak Irez, Emin Bayraktar, Ibrahim Miskioglu Feb 2020

Fracture Toughness Analysis Of Epoxy-Recycled Rubber-Based Composite Reinforced With Graphene Nanoplatelets For Structural Applications In Automotive And Aeronautics, Alaeddin Burak Irez, Emin Bayraktar, Ibrahim Miskioglu

Michigan Tech Publications

This study proposes a new design of lightweight and cost-efficient composite materials for the aeronautic industry utilizing recycled fresh scrap rubber, epoxy resin, and graphene nanoplatelets (GnPs). After manufacturing the composites, their bending strength and fracture characteristics were investigated by three-point bending (3PB) tests. Halpin-Tsai homogenization adapted to composites containing GnPs was used to estimate the moduli of the composites, and satisfactory agreement with the 3PB test results was observed. In addition, 3PB tests were simulated by finite element method incorporating the Halpin-Tsai homogenization, and the resulting stress-strain curves were compared with the experimental results. Mechanical test results showed that …


Publisher Correction: Evaporation Of A Sessile Droplet On A Slope., Mitch Timm, Esmaeil Dehdashti, Amir Jarrahi Darban, Hassan Masoud Feb 2020

Publisher Correction: Evaporation Of A Sessile Droplet On A Slope., Mitch Timm, Esmaeil Dehdashti, Amir Jarrahi Darban, Hassan Masoud

Michigan Tech Publications

An amendment to this paper has been published and can be accessed via a link at the top of the paper.


Characterizing Meteorological Forecast Impact On Microgrid Optimization Performance And Design, Robert Jane, Gordon G. Parker, Gail Vaucher, Morris Berman Jan 2020

Characterizing Meteorological Forecast Impact On Microgrid Optimization Performance And Design, Robert Jane, Gordon G. Parker, Gail Vaucher, Morris Berman

Michigan Tech Publications

A microgrid consists of electrical generation sources, energy storage assets, loads, and the ability to function independently, or connect and share power with other electrical grids. Thefocus of this work is on the behavior of a microgrid, with both diesel generator and photovoltaic resources, whose heating or cooling loads are influenced by local meteorological conditions. Themicrogrid's fuel consumption and energy storage requirement were then examined as a function of the atmospheric conditions used by its energy management strategy (EMS). A fuel-optimal EMS, able to exploit meteorological forecasts, was developed and evaluated using a hybrid microgrid simulation. Weather forecast update periods …


Tra-1-60-Positive/Cd45low Cells Found In The Peripheral Blood Of Prostate Cancer Patients With Metastatic Disease – A Proof-Of-Concept Study, Claudia Schäfer, Yawen Ju, Youngbin Tak, Cesar Vazquez, Sangyoon J. Han, Edwin Tan, Et Al. Jan 2020

Tra-1-60-Positive/Cd45low Cells Found In The Peripheral Blood Of Prostate Cancer Patients With Metastatic Disease – A Proof-Of-Concept Study, Claudia Schäfer, Yawen Ju, Youngbin Tak, Cesar Vazquez, Sangyoon J. Han, Edwin Tan, Et Al.

Michigan Tech Publications

Purpose

Over 90% of all cancer related deaths are due to metastasis. However, current diagnostic tools can't reliably discriminate between invasive and localized cancers.

Patients and methods

In this proof-of-concept study, we employed the embryonic stem cell marker TRA-1-60 (TRA+) to identify TRA + cells within the blood of prostate cancer patients and searched for TRA + cells in men with metastatic and localized cancers. We isolated whole peripheral blood mononuclear cells from 26 metastatic prostate cancer patients, from 13 patients with localized prostate cancer and from 17 healthy controls. Cells were stained for DAPI, CD45 and TRA + by …


Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar Jan 2020

Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar

Michigan Tech Publications

We study a Multiple Depot Heterogeneous Traveling Salesman Problem (MDHTSP) where the cost of the traveling between any two targets depends on the type of the vehicle. The travel costs are assumed to be symmetric, satisfy the triangle inequality, and are monotonic, i.e., the travel costs between any two targets monotonically increases with the index of the vehicles. Exploiting the monotonic structure of the travel costs, we present a 2-approximation algorithm based on the primal-dual method.


Agile Stage-Gate Management (Asgm) For Physical Products, John J. Salvato, Andre O. Laplume Jan 2020

Agile Stage-Gate Management (Asgm) For Physical Products, John J. Salvato, Andre O. Laplume

Michigan Tech Publications

We present a qualitative study of Agile Stage-Gate Management (ASGM),: a hybrid new product development methodology that combines Agile and Stage-Gate Management (SGM) approaches for the coordination of new product development. When applied to software projects, Agile is expected to deliver reduced development times, improved resource utilization, and greater financial success. We examine whether ASGM practitioners realize similar outcomes in a sample of global firms developing complex electro-mechanical products (e.g., automobile components, railway propulsion systems, and medical devices). Our grounded theory approach articulates an understanding of ASGM through extensive interviews of experienced professionals. Our thematic analysis supports many expected benefits …