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In this paper, the authors present their experiences from participating in a National Science Foundation (NSF) I-Corps L training program established for business startups, using Blank's Lean LaunchPad, Osterwalder's Business Model Canvas, and associated tools. They used the entrepreneurial skills acquired through this training to scale-up their emerging innovation, the Cincinnati Engineering Enhanced Math and Science Program (CEEMS), which had been developed, implemented, and evaluated with successful results over a period of seven years in a targeted 14 school-district partnership in Greater Cincinnati. The overriding goal was to improve student learning and success rates in K-12 math and science courses by helping to accelerate the process of bringing effective educational innovation, CEEMS, to scale. In CEEMS, teachers were trained in using challenge-based learning (CBL) and the engineering design process (EDP), teaching pedagogies to transform their classrooms into student-centered, hands-on learning environments, while also assisting students to improve their evaluation scores related to science, math, and engineering instruction. CEEMS teachers acquired the necessary skills through coursework, professional development (PD) workshops, and longitudinal professional guidance provided by assigned coaches over a period of two years to become proficient in developing CBL-EDP curriculum, teaching it, and assessing student learning and reflecting after teaching. The authors have documented how they used customer market research conducted during the I-Corps L training to define their minimum viable product (MVP) to duplicate the successful CEEMS methodology through a condensed (=16 week) self-paced, completely online training program with virtual coaching support. The authors also describe the process they used to move forward very quickly from an MVP to a more complete product offering, its branding, the process of trademarking it, and finally licensing it to an established non-profit organization (NPO) for future marketing. Details of the whole experience are presented with the hope that it will serve as a useful guide for other venture creators.

In this paper, a differential quadrature method is presented for computation of the fundamental frequency of a thin rectangular isotropic elastic plate with variable thickness. In this method, a partial derivative of a function with respect to a space variable at a discrete point is approximated as a weighted linear sum of the function values at all discrete points in the region of that variable. The weighting coefficients are treated as the unknowns. Applying this concept to each partial derivative of the free vibration differential equation of motion of the plate gives a set of linear simultaneous equations, which are solved for the unknown weightage coefficients by accounting for the boundary conditions. The method is used to evaluate the fundamental frequency of linearly tapered plates with simply supported, fully clamped, and mixed boundary conditions. Results are compared with existing solutions available from other analytical and numerical methods. The method presented gives accurate results and is computationally efficient., The fundamental frequency of rectangular thin plates may be measured by a new calculation technique. The technique is the differential quadrature method which ovecomes limitations inherent in other techniques. The advantages of the numerical technique grounded in differential quadrature method which discretizes the domain are that it is a polynomial fitting method which satisfies the boundary conditions in analysis and that it needs less computational time.

A finite element procedure for the dynamic analysis of rigid airport pavements with discontinuities is presented. The analysis procedure considers the dynamic interaction between aircraft and a rigid pavement. The rigid pavement is modeled as a series of discontinuous, thin-plate finite elements resting on a viscoelastic foundation. At the discontinuities, the load transfer devices are modeled as vertical springs, the stiffness of which depends on the dowel properties and the dowel-concrete interaction. The viscoelastic foundation is modeled by distributed springs and dashpots. The moving aircraft loads are represented by masses supported by linear spring and dashpot systems, which have specified horizontal velocities and accelerations. Numerical results obtained from the analytical formulation presented are compared with available analytical solutions and experimental data. A parametric study is conducted to determine the effects of the various parameters on the dynamic response of jointed rigid pavements to moving loads., The dynamic response of discontinuous pavements under dynamic aircraft loads is studied using the finite element method. The pavement is modeled as discrete plates joined at the discontinuities by vertical springs that represent the load transfer devices, supported by a viscoelastic soil foundation modeled as springs and dashpots. The aircraft suspension system is modeled as linear springs and dashpots supporting the aircraft mass. A parametric study is also conducted to investigate the effects of certain parameters on the performance of joints subjected to dynamic loads.

This paper presents an approach toward formulating analytical models to predict the moment-rotation hysteresis behavior of top and seat angle connections. Experimental results obtained from 12 top and seat angle connection specimens are used to obtain the prediction equations for the parameters defining the moment rotation hysteresis loops of a typical top and seat angle connection. These parameters include the initial stiffness, ultimate moment capacity, ultimate rotation, the transition moment, characteristic moment, and rigidity parameter. Regression analysis results and comparisons with test results are presented to demonstrate the acceptability of these prediction equations. The prediction equations obtained for these parameters are used to develop four different moment rotation hysteresis models for the connection: the bilinear, elastoplastic, Ramberg-Osgood, and modified bilinear models. The results of the study show that the top and seat angle connection behaves as a semirigid connection. A wide range of initial stiffnesses and ultimate moment capacities are possible to achieve by altering the connection geometry related variables within a practical range. For certain geometric configurations of the connection, significant transfer of moment from the beam to the column can occur before the connection fails. Also, it is possible to design a connection with flow stiffness and small moment transfer capability, so that it behaves in a manner such that it is close to being classified as a pin connection. The prediction equations developed for the parameters characterizing the four hysteresis models give acceptable results when compared to experimental results. The degree to which the models idealize the actual behavior varies with the elastoplastic model being the least conservative and the modified bilinear model being the best. The Ramberg-Osgood model is the most accurate in just modeling the nonpinching moment-rotation loops.

Over the past 10 years there has been a growing need to introduce closed-loop control technology for vibration suppression of buildings subject to wind or earthquake disturbances. This paper deals with the investigation of the effectiveness of a fuzzy logic based time variable damping tuned mass damper (TMD) on a building structure undergoing free and forced vibrations. The uniqueness of this approach is the application of a robust, nonlinear fuzzy based controller to emulate a time-optimal control strategy. Fuzzy logic based time variable damping is introduced into a semi-active TMD in order to enhance its performance in the vibration suppression of buildings. First, a single story structure for three different vibration suppression approaches is studied. The fuzzy logic based time variable damping TMD (fuzzy TMD) is compared to the baseline passive TMD as well as a conventional proportional-derivative (PD) controller. Forced vibration is introduced using a resonant harmonic sinusoidal excitation (i.e. same frequency as the fundamental frequency of the structure). Finally, the fuzzy TMD is compared to the baseline for the free vibration of a 15 story structure. For both structures studied, MATLAB® based simulation results show that the passive TMD and the PD, both constant gain approaches, provide similar results whereas the fuzzy TMD yields half the settling time. This effort clearly demonstrates the potential of a variable gain (damping) strategy for the vibration suppression of buildings. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the prying behavior in thick-flange built-up T-stub/column systems that should be addressed in designing full-strength double tee connections for use in moment resisting frames which satisfy prequalification requirements. In particular, this study focuses on the phenomenon herein indicated as secondary prying, which is related to the additional forces that are introduced into the tension bolts due to significant bending of the column flange. Three-dimensional finite element models that incorporate pretension of fasteners, full contact interactions, and nonlinear material characteristics are used to investigate secondary prying effect in thick-flange T-stub/column system with and without continuity plates. This study provides insight as to whether continuity plates are necessary in columns when designing and detailing full-scale T-stub connections for prequalification. The effect of secondary prying is incorporated into an existing prying strength model for thick T-stubs to quantify the amount of total prying encountered in thick built-up T-stub connections with and without continuity plates. Parameters that impact the secondary prying in thick flange T-stub/column systems were identified based on the geometric configuration that results from the design of full-strength double tee connections with deep girders. The results show that decreasing the effect of secondary prying is achieved through either increasing the column size, or adding continuity plates to the column. This study provides information for detailing columns without continuity plates as well as quantifying the amount of prying so engineers can design for the additional load by increasing the bolt diameter. [Copyright &y& Elsevier]

In this paper, the authors present their experiences from participating in a National Science Foundation (NSF) I-Corps L training program established for business startups, using Blank's Lean LaunchPad, Osterwalder's Business Model Canvas, and associated tools. They used the entrepreneurial skills acquired through this training to scale-up their emerging innovation, the Cincinnati Engineering Enhanced Math and Science Program (CEEMS), which had been developed, implemented, and evaluated with successful results over a period of seven years in a targeted 14 school-district partnership in Greater Cincinnati. The overriding goal was to improve student learning and success rates in K–12 math and science courses by helping to accelerate the process of bringing effective educational innovation, CEEMS, to scale. In CEEMS, teachers were trained in using challenge-based learning (CBL) and the engineering design process (EDP), teaching pedagogies to transform their classrooms into student-centered, hands-on learning environments, while also assisting students to improve their evaluation scores related to science, math, and engineering instruction. CEEMS teachers acquired the necessary skills through coursework, professional development (PD) workshops, and longitudinal professional guidance provided by assigned coaches over a period of two years to become proficient in developing CBL–EDP curriculum, teaching it, and assessing student learning and reflecting after teaching. The authors have documented how they used customer market research conducted during the I-Corps L training to define their minimum viable product (MVP) to duplicate the successful CEEMS methodology through a condensed (≤16 week) self-paced, completely online training program with virtual coaching support. The authors also describe the process they used to move forward very quickly from an MVP to a more complete product offering, its branding, the process of trademarking it, and finally licensing it to an established non-profit organization (NPO) for future marketing. Details of the whole experience are presented with the hope that it will serve as a useful guide for other venture creators. [ABSTRACT FROM AUTHOR]

The results of a series of finite-element (FE) simulations and experimental studies are used to develop two prying models that predict the failure strength of thick-flange built-up T-stub connections with complete joint penetration (CJP) and fillet welds. A parametric study based on identifying the major geometric and force-related parameters that vary within current acceptable steel fabrication and design practices is used to select the cases for analysis. The strength prying models predict the capacity of thick-flange built-up T-stub connections with CJP and fillet welds for the failure limit state of the partial yielding tension flange followed by bolt fracture. The accuracy of the developed strength models are verified with FE results of built-up T-stubs designed for full strength compared with existing models reported in the literature. Based on the results of this study, a refined design procedure that takes into account the partial yielding in thick-flange T-stubs is proposed. [ABSTRACT FROM AUTHOR]