Matching Items (636)
Filtering by
- All Subjects: Mechanical Engineering
- Creators: Arizona State University
Description
Since its launch by the US Green Building Council (USGBC), Leadership in Energy and Environmental Design (LEED) certification has been postured as the "gold standard" for environmentally conscious, sustainable building design, construction and operations. However, as a "living measurement", one which requires ongoing evaluation and reporting of attainment and compliance with LEED certification requirements, there is none. Once awarded, LEED certification does not have a required reporting component to effectively track continued adherence to LEED standards. In addition, there is no expiry tied to the certification; once obtained, a LEED certification rating is presumed to be a valid representation of project certification status. Therefore, LEED lacks a requirement to demonstrate environmental impact of construction materials and building systems over the entire life of the project. Consequently, LEED certification is merely a label rather than a true representation of ongoing adherence to program performance requirements over time. Without continued monitoring and reporting of building design and construction features, and in the absence of recertification requirements, LEED is, in reality, a gold star rather than a gold standard. This thesis examines the lack of required ongoing monitoring, reporting, or recertification requirements following the award by the USGBC of LEED certification; compares LEED with other international programs which do have ongoing reporting or recertification requirements; demonstrates the need and benefit of ongoing reporting or recertification requirements; and explores possible methods for implementation of mandatory reporting requirements within the program.
ContributorsCarpenter, Anne Therese (Author) / Olson, Larry (Thesis advisor) / Hild, Nicholas (Committee member) / Brown, Albert (Committee member) / Arizona State University (Publisher)
Created2013
Description
Objective: The aim of this research is to uncover, via a comprehensive cross study analysis, data patterns that could potentially point to a positive correlation between two main variables: anesthetic monitoring equipment and anesthetic decision making. Of particular interest is the equipment's monitor screen and the extent to which its user interface design influences anesthetic situation awareness (SA) and hence, decision making. It is hypothesized that poor anesthetic diagnosis from inadequate SA may be largely attributable to patient data displays lacking in human factors design considerations. Methods: A systematic search was conducted of existing empirical studies pertaining to patient physiologic monitoring that spanned across interrelated domains, namely, ergonomics, medical informatics, visual computing, cognitive psychology, human factors, clinical monitoring, intensive care medicine, and intelligent systems etc. all published in scholarly research journals between 1970 to August 2012. Anesthetic-related keywords were queried i.e. anesthetic mishaps, patient physiological data displays, anesthetic vigilance etc. (found in Appendix A). This approach yielded a few thousand results, of which 65 empirical studies were pulled. Further extraction of articles having direct connection to the use of data displays within the anesthetic context produced a total of 20 empirical studies. These studies were grouped under two broad categories of Monitoring and Monitors whereby factors directly contributing to the studies' results were identified with the aim to find emerging themes that provide insights involving interface design and medical decision making. Results: There is a direct correlation between user-interface design and decision making. The situation awareness (SA) required for decision making heavily relies upon data displays oriented towards information extraction and integration. In the systematic assessment of empirical studies, it is undeniable how strikingly prominent visual attributes show up as contributing factors to subjects' enhanced performance in the studies. Conclusions: How and to what users direct their perceptual and cognitive resources necessarily influence their perception of the environment, and by extension, their development of situation awareness (SA). Although patient monitoring equipment employed in anesthetic practice has proven to be indispensable in quality patient care, graphical representations of patient data is still far from optimal in the clinical setting. User-interfaces that lend decision support to facilitate SA and subsequent decision making is critical in crisis management.
ContributorsNguyen, Angie (Author) / Velasquez, Joseph (Thesis advisor) / McDermott, Lauren (Thesis advisor) / Herring, Don (Committee member) / Branaghan, Russell (Committee member) / Arizona State University (Publisher)
Created2013
Description
Derived from the necessity to increase testing capabilities of hybrid rocket motor (HRM) propulsion systems for Daedalus Astronautics at Arizona State University, a small-scale motor and test stand were designed and developed to characterize all components of the system. The motor is designed for simple integration and setup, such that both the forward-end enclosure and end cap can be easily removed for rapid integration of components during testing. Each of the components of the motor is removable allowing for a broad range of testing capabilities. While examining injectors and their potential it is thought ideal to obtain the highest regression rates and overall motor performance possible. The oxidizer and fuel are N2O and hydroxyl-terminated polybutadiene (HTPB), respectively, due to previous experience and simplicity. The injector designs, selected for the same reasons, are designed such that they vary only in the swirl angle. This system provides the platform for characterizing the effects of varying said swirl angle on HRM performance.
ContributorsSummers, Matt H (Author) / Lee, Taewoo (Thesis advisor) / Chen, Kangping (Committee member) / Wells, Valana (Committee member) / Arizona State University (Publisher)
Created2013
Description
The research presented explores traditional Chinese visual design elements with a goal of incorporating them into contemporary design. It seeks to provide insight into how Chinese and non-Chinese designers and non-designers recognize common visual design elements as being associated with Chinese design. As a result, the research explores three characteristics: a) handicraft; b) naturalism; and c) design with meaning, which can be key points in understanding traditional Chinese design. Furthermore, the research explores two sets of design criteria that can guide designers to apply these representative design elements into contemporary design in order to express Chinese culture.
ContributorsRen, Liqi (Author) / Giard, Jacques (Thesis advisor) / Brown, Claudia (Committee member) / Cheung, Patrick (Committee member) / Arizona State University (Publisher)
Created2013
Description
The development of advanced, anthropomorphic artificial hands aims to provide upper extremity amputees with improved functionality for activities of daily living. However, many state-of-the-art hands have a large number of degrees of freedom that can be challenging to control in an intuitive manner. Automated grip responses could be built into artificial hands in order to enhance grasp stability and reduce the cognitive burden on the user. To this end, three studies were conducted to understand how human hands respond, passively and actively, to unexpected perturbations of a grasped object along and about different axes relative to the hand. The first study investigated the effect of magnitude, direction, and axis of rotation on precision grip responses to unexpected rotational perturbations of a grasped object. A robust "catch-up response" (a rapid, pulse-like increase in grip force rate previously reported only for translational perturbations) was observed whose strength scaled with the axis of rotation. Using two haptic robots, we then investigated the effects of grip surface friction, axis, and direction of perturbation on precision grip responses for unexpected translational and rotational perturbations for three different hand-centric axes. A robust catch-up response was observed for all axes and directions for both translational and rotational perturbations. Grip surface friction had no effect on the stereotypical catch-up response. Finally, we characterized the passive properties of the precision grip-object system via robot-imposed impulse perturbations. The hand-centric axis associated with the greatest translational stiffness was different than that for rotational stiffness. This work expands our understanding of the passive and active features of precision grip, a hallmark of human dexterous manipulation. Biological insights such as these could be used to enhance the functionality of artificial hands and the quality of life for upper extremity amputees.
ContributorsDe Gregorio, Michael (Author) / Santos, Veronica J. (Thesis advisor) / Artemiadis, Panagiotis K. (Committee member) / Santello, Marco (Committee member) / Sugar, Thomas (Committee member) / Helms Tillery, Stephen I. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Locomotion of microorganisms is commonly observed in nature and some aspects of their motion can be replicated by synthetic motors. Synthetic motors rely on a variety of propulsion mechanisms including auto-diffusiophoresis, auto-electrophoresis, and bubble generation. Regardless of the source of the locomotion, the motion of any motor can be characterized by the translational and rotational velocity and effective diffusivity. In a uniform environment the long-time motion of a motor can be fully characterized by the effective diffusivity. In this work it is shown that when motors possess both translational and rotational velocity the motor transitions from a short-time diffusivity to a long-time diffusivity at a time of pi/w. The short-time diffusivities are two to three orders of magnitude larger than the diffusivity of a Brownian sphere of the same size, increase linearly with concentration, and scale as v^2/2w. The measured long-time diffusivities are five times lower than the short-time diffusivities, scale as v^2/{2Dr [1 + (w/Dr )^2]}, and exhibit a maximum as a function of concentration. The variation of a colloid's velocity and effective diffusivity to its local environment (e.g. fuel concentration) suggests that the motors can accumulate in a bounded system, analogous to biological chemokinesis. Chemokinesis of organisms is the non-uniform equilibrium concentration that arises from a bounded random walk of swimming organisms in a chemical concentration gradient. In non-swimming organisms we term this response diffusiokinesis. We show that particles that migrate only by Brownian thermal motion are capable of achieving non-uniform pseudo equilibrium distribution in a diffusivity gradient. The concentration is a result of a bounded random-walk process where at any given time a larger percentage of particles can be found in the regions of low diffusivity than in regions of high diffusivity. Individual particles are not trapped in any given region but at equilibrium the net flux between regions is zero. For Brownian particles the gradient in diffusivity is achieved by creating a viscosity gradient in a microfluidic device. The distribution of the particles is described by the Fokker-Planck equation for variable diffusivity. The strength of the probe concentration gradient is proportional to the strength of the diffusivity gradient and inversely proportional to the mean probe diffusivity in the channel in accordance with the no flux condition at steady state. This suggests that Brownian colloids, natural or synthetic, will concentrate in a bounded system in response to a gradient in diffusivity and that the magnitude of the response is proportional to the magnitude of the gradient in diffusivity divided by the mean diffusivity in the channel.
ContributorsMarine, Nathan Arasmus (Author) / Posner, Jonathan D (Thesis advisor) / Adrian, Ronald J (Committee member) / Frakes, David (Committee member) / Phelan, Patrick E (Committee member) / Santos, Veronica J (Committee member) / Arizona State University (Publisher)
Created2013
Description
Human fingertips contain thousands of specialized mechanoreceptors that enable effortless physical interactions with the environment. Haptic perception capabilities enable grasp and manipulation in the absence of visual feedback, as when reaching into one's pocket or wrapping a belt around oneself. Unfortunately, state-of-the-art artificial tactile sensors and processing algorithms are no match for their biological counterparts. Tactile sensors must not only meet stringent practical specifications for everyday use, but their signals must be processed and interpreted within hundreds of milliseconds. Control of artificial manipulators, ranging from prosthetic hands to bomb defusal robots, requires a constant reliance on visual feedback that is not entirely practical. To address this, we conducted three studies aimed at advancing artificial haptic intelligence. First, we developed a novel, robust, microfluidic tactile sensor skin capable of measuring normal forces on flat or curved surfaces, such as a fingertip. The sensor consists of microchannels in an elastomer filled with a liquid metal alloy. The fluid serves as both electrical interconnects and tunable capacitive sensing units, and enables functionality despite substantial deformation. The second study investigated the use of a commercially-available, multimodal tactile sensor (BioTac sensor, SynTouch) to characterize edge orientation with respect to a body fixed reference frame, such as a fingertip. Trained on data from a robot testbed, a support vector regression model was developed to relate haptic exploration actions to perception of edge orientation. The model performed comparably to humans for estimating edge orientation. Finally, the robot testbed was used to perceive small, finger-sized geometric features. The efficiency and accuracy of different haptic exploratory procedures and supervised learning models were assessed for estimating feature properties such as type (bump, pit), order of curvature (flat, conical, spherical), and size. This study highlights the importance of tactile sensing in situations where other modalities fail, such as when the finger itself blocks line of sight. Insights from this work could be used to advance tactile sensor technology and haptic intelligence for artificial manipulators that improve quality of life, such as prosthetic hands and wheelchair-mounted robotic hands.
ContributorsPonce Wong, Ruben Dario (Author) / Santos, Veronica J (Thesis advisor) / Artemiadis, Panagiotis K (Committee member) / Helms Tillery, Stephen I (Committee member) / Posner, Jonathan D (Committee member) / Runger, George C. (Committee member) / Arizona State University (Publisher)
Created2013
Description
The process of this study involves conducting empirical tests on consumer's emotional responses toward tableware designs by statistic measurements (PrEmo), including both Chinese and American cultures. The objective to this study is to research the correlation between consumers' cognitive analysis of Chinese tableware designs and their emotional responses. The author proposes that the correlationship between consumers' cognition of Chinese tableware and emotional responses will lead to a new opportunity in the industrial design industry. Fifty-seven people responded to sixty-seven invitations to join the research project at Chinese restaurants in both China and America. Throughout the process of coding and organizing the survey data, a finding shows that there is a connection between consumer sensitivity toward the products and their emotional bonds to the assigned product designs. The data showed that more people in China are expending greater effort in choosing suitable tableware designs compared to the people in the U.S. Key words: Emotion, Cognition, Culture, Tableware design, Chinese restaurants
ContributorsLiu, Ran (Author) / Herring, Donald (Thesis advisor) / Wolf, Peter (Committee member) / Wang, Ning (Committee member) / Arizona State University (Publisher)
Created2013
Description
Much of the literature and many of the studies surrounding brainstorming focus on the performance and the quantitative aspects of the process in comparing the efficacy of individual versus group settings, specifically the benefits and pitfalls associated with each. This study looked at using alternate combinations of both individual and group styles of brainstorming to most efficiently maximize production of ideas and satisfaction of participants, while minimizing obstacles and shortcomings typically seen in brainstorming sessions. This research was designed to compare results of three different aspects of these sessions: real efficacy, perceived efficacy, and participant satisfaction. Two cohorts of eight student volunteers each were used to participate in and evaluate the specific session sequence they attended, either that of group then individual or individual then group. Each cohort consisted of four introverts and four extroverts, and the results and responses of each were then compared against each other in the same session and then against the results of the other session to see if there was a difference between the two personality types. The findings of this research revealed that the brainstorming session sequence of group then individual generated a larger quantity of solutions to the given problem and was perceived as more effective by both introverts and extroverts. The study also showed that introverts self-reported a higher satisfaction for the session ending in individual brainstorming, while the extroverts preferred the session ending with the group brainstorming.
ContributorsMarinello, Michael (Author) / Heywood, William (Thesis advisor) / Christensen, Tamara (Committee member) / Wolf, Peter (Committee member) / Arizona State University (Publisher)
Created2013
Description
The atomization of a liquid jet by a high speed cross-flowing gas has many applications such as gas turbines and augmentors. The mechanisms by which the liquid jet initially breaks up, however, are not well understood. Experimental studies suggest the dependence of spray properties on operating conditions and nozzle geom- etry. Detailed numerical simulations can offer better understanding of the underlying physical mechanisms that lead to the breakup of the injected liquid jet. In this work, detailed numerical simulation results of turbulent liquid jets injected into turbulent gaseous cross flows for different density ratios is presented. A finite volume, balanced force fractional step flow solver to solve the Navier-Stokes equations is employed and coupled to a Refined Level Set Grid method to follow the phase interface. To enable the simulation of atomization of high density ratio fluids, we ensure discrete consistency between the solution of the conservative momentum equation and the level set based continuity equation by employing the Consistent Rescaled Momentum Transport (CRMT) method. The impact of different inflow jet boundary conditions on different jet properties including jet penetration is analyzed and results are compared to those obtained experimentally by Brown & McDonell(2006). In addition, instability analysis is performed to find the most dominant insta- bility mechanism that causes the liquid jet to breakup. Linear instability analysis is achieved using linear theories for Rayleigh-Taylor and Kelvin- Helmholtz instabilities and non-linear analysis is performed using our flow solver with different inflow jet boundary conditions.
ContributorsGhods, Sina (Author) / Herrmann, Marcus (Thesis advisor) / Squires, Kyle (Committee member) / Chen, Kangping (Committee member) / Huang, Huei-Ping (Committee member) / Tang, Wenbo (Committee member) / Arizona State University (Publisher)
Created2013