Thesis (Ph.D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2000. / Includes bibliographical references (leaves 135-140). / Tomorrow's ubiquitous computing environments will go beyond the keyboard, mouse and monitor paradigm of interaction and will require the automatic interpretation of human motion using a variety of sensors including video cameras. I present several techniques for human motion recognition that are inspired by observations on human gesture, the class of communicative human movement. Typically, gesture recognition systems are unable to handle systematic variation in the input signal, and so are too brittle to be applied successfully in many real-world situations. To address this problem, I present modeling and recognition techniques to adapt gesture models to the situation at hand. A number of systems and frameworks that use adaptive gesture models are presented. First, the parametric hidden Markov model (PHMM) addresses the representation and recognition of gesture families, to extract how a gesture is executed. Second, strong temporal models drawn from natural gesture theory are exploited to segment two kinds of natural gestures from video sequences. Third, a realtime computer vision system learns gesture models online from time-varying context. Fourth, a realtime computer vision system employs hybrid Bayesian networks to unify and extend the previous approaches, as well as point the way for future work. / by Andrew David Wilson. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2011. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 93-98). / Computers as we know them are fading into the background. However, interaction modalities developed for "foreground" computer systems are beginning to seep into the day-to-day interactions that people have with each other and the objects around them. The Prototouch system allows user interface designers to quickly prototype systems of ubiquitous computing devices which utilize touch and gesture based interactions popularized by the recent explosion of multitouch-enabled smartphones, enabling the user to act as container, token, and tool for the manipulation and transportation of abstract digital information between these devices. Two versions of the system utilizing different network topologies have been created, and several example applications utilizing the system have been developed. / by David Cranor. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 1998. / Includes bibliographical references (leaves 69-71). / by Brenden Courtney Maher. / M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2006. / Includes bibliographical references (leaves [125]-132). / This thesis presents a quantitative, parametric model for describing musical tension. While the phenomenon of tension is evident to listeners, it is difficult to formalize due to its subjective and multi-dimensional nature. The model is therefore derived from empirical data. Two experiments with contrasting approaches are described. The first experiment is an online test with short musical excerpts and multiple choice answers. The format of the test makes it possible to gather large amounts of data. The second study requires fewer subjects and collects real-time responses to musical stimuli. Both studies present test subjects with examples that take into account a number of musical parameters including harmony, pitch height, melodic expectation, dynamics, onset frequency, tempo, and rhythmic regularity. The goal of the first experiment is to confirm that the individual musical parameters contribute directly to the listener's overall perception of tension. The goal of the second experiment is to explore linear and nonlinear models for predicting tension given descriptions of the musical parameters for each excerpt. The resulting model is considered for potential incorporation into computer-based applications. Specifically, it could be used as part of a computer-assisted composition environment. One such application, Hyperscore, is described and presented as a possible platform for integration. / by Morwaread M. Farbood. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2001. / Includes bibliographical references (leaves 68-75). / A real-time synthesis engine which models and predicts the timbre of acoustic instruments based on perceptual features extracted from an audio stream is presented. The thesis describes the modeling sequence including the analysis of natural sounds, the inference step that finds the mapping between control and output parameters, the timbre prediction step, and the sound synthesis. The system enables applications such as cross-synthesis, pitch shifting or compression of acoustic instruments, and timbre morphing between instrument families. It is fully implemented in the Max/MSP environment. The Perceptual Synthesis Engine was developed for the Hyperviolin as a novel, generic and perceptually meaningful synthesis technique for non-discretely pitched instruments. / by Tristan Jehan. / S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2012. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 92-96). / The loss of a limb is extremely debilitating. Unfortunately, today's assistive technologies are still far from providing fully functional artificial limb replacements. Although lower extremity prostheses are currently better able to give assistance than their upper-extremity counterparts, important locomotion problems still remain for leg amputees. Instability, gait asymmetry, decreased walking speeds and high metabolic energy costs are some of the main challenges requiring the development of a new kind of prosthetic device. These challenges point to the need for highly versatile, fully integrated lower-extremity powered prostheses that can replicate the biological behavior of the intact human leg. This thesis presents the design and evaluation of a novel biomimetic active knee prosthesis capable of emulating intact knee biomechanics during level-ground walking. The knee design is motivated by a mono-articular prosthetic knee model comprised of a variable damper and two series elastic clutch units spanning the knee joint. The powered knee system is comprised of two series-elastic actuators positioned in parallel in an agonist-antagonist configuration. This investigation hypothesizes that the biomimetic active-knee prosthesis, with a variable impedance control, can improve unilateral transfemoral amputee locomotion in level-ground walking, reducing the metabolic cost of walking at selfselected speeds. To evaluate this hypothesis, a preliminary study investigated the clinical impact of the active knee prosthesis on the metabolic cost of walking of four unilateral above-knee amputees. This preliminary study compared the antagonistic active knee prosthesis with subjects' prescribed knee prostheses. The subjects' prescribed prostheses encompass four of the leading prosthetic knee technologies commercially available, including passive and electronically controlled variable-damping prosthetic systems. Use of the novel biomimetic active knee prosthesis resulted in a metabolic cost reduction for all four subjects by an average of 5.8%. Kinematic and kinetic analyses indicate that the active knee can increase self-selected walking speed in addition to reducing upper body vertical displacement during walking by an average of 16%. The results of this investigation report for the first time a metabolic cost reduction when walking with a prosthetic system comprised of an electrically powered active knee and passive foot-ankle prostheses, as compared to walking with a conventional transfemoral prosthesis. With this work I aim to advance the field of biomechatronics, contributing to the development of integral assistive technologies that adapt to the needs of the physically challenged. / by Ernesto Carlos Martinez-Villalpando. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005. / Includes bibliographical references (leaves 78-81). / Too often, efforts toward re-thinking learning environments focus solely on the cognitive aspects of education. By expanding our view to consider other aspects of adolescent development involved in education, we can begin to address the needs of the whole child. This research aims to 1) gain a better understanding of the effects of immediate emotions in middle school academic contexts and 2) create a system geared toward addressing the emotional needs of teenage girls. To support emotional self-awareness and empathy, a proactive emotional health was developed. This is a part of a long-term research plan for understanding the role that digital technology can play in helping address emotions and support learning for teenage girls. The system, G.I.R.L.S (Girls Involved in Real Life Sharing) Talk, allows users to reflect actively upon the emotions related to their situations through the construction of pictorial narratives. Users of this new system were able to gain new knowledge and understanding about themselves and others through the exploration of authentic and personal experiences. The system employs a new technology called common sense reasoning that enables it to infer affective content from the users' stories and support emotional reflection. This system has been evaluated with seventeen subjects; one group used the G.I.R.L.S. Talk system with emotional reflection support, while the control group used the system without the support. Over three weeks, the group supported with common sense reasoning about emotion increased the variety of emotion words used in their writing; the control group showed no such increase. / (cont.) In both cases, the system enabled the subjects to express themselves freely in a comfortable and meaningful way. Overall, this thesis makes three main contributions: 1) new insights into the effects of immediate emotions in academic situations for adolescents, 2) a new system for supporting teenage girls' emotional self-awareness and empathy, and 3) new insight into the value of utilizing constructionist technologies in proactive emotional health systems. / by Shaundra Bryant Daily. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005. / Includes bibliographical references. / Ubiquitous computing is transforming interior design by allowing utilities, goods and information to be delivered where and when we need them. How will new information technologies impact the design of interior spaces? Intelligent interiors can be more flexible and expressive than traditional spaces. Automation, personal fabrication and augmented reality can be applied to interior spaces with new interaction modes that operate at an architectural scale. Water, light, and other utilities can be automated in a way that empowers users by providing direct feedback, tangible benefit and being fail-soft. Appliances can make it possible to produce and recycle a large number of variable goods locally and on demand. Many of the objects and surfaces of interior spaces can serve as displays to provide information intuitively where and when it is needed. This thesis demonstrates how distributed intelligence can increase productivity and enrich the experience of interior spaces. Experiments with augmentations to the utilities, goods and information of a working kitchen suggest guidelines for interaction with intelligent interior spaces. The perceptual load and quality of interaction needs to be balanced; for example in our experiments projected text was almost always distracting. / (cont.) This work demonstrated that: information should behave at the scale of architectural space; an intelligent interior space should provide as much fidelity at the lowest bandwidth possible to support activity without distracting from tasks; the association of information to the tasks and objects referred to should be concrete and obvious; and appropriate feedback should accompany new interaction to increase the control and confidence of users. This thesis shows that new interaction modes for interior spaces can be intuitively understood and valued. In addition to being more flexible and functional, intelligent interiors can enrich everyday activity with new sensory experiences. / by Leonardo Amerigo Bonanni. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2000. / Includes bibliographical references (leaves 82-85). / In the real world, people clothe themselves in garments whose cut and design encodes information about their social identity. This encoding changes temporally as the design spreads throughout a population: this is the basis of "fashion." A similar sense of fashion has emerged on the World Wide Web (WWW), as people embellish their homesites with links, pictures, and other objects that exhibit similar patterns of dispersion. I have developed tools and algorithms for tracking and analyzing this "virtual fashion." The initial approach is to examine a set of selected homesites each week and track the spread of links. By developing a system for collecting and analyzing the data, this research provides both macro and micro readings of the phenomenon of virtual fashion. The system shows what is popular, ways that things are related, and what is emerging online. I also use data collected by the system to think about existing social theories of fashion and see how they may help develop models of virtual fashion. This research helps people further understand how the WWW functions as a social environment. / Ta-gang Chiou. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2002. / Includes bibliographical references (p. 169-172). / A hardware and software platform has been designed and implemented for modeling, testing, and deploying distributed peer-to-peer sensor networks comprised of many identical nodes. Each node possesses the tangible affordances of a commonplace pushpin to meet ease-of-use and power considerations. The sensing, computational, and communication abilities of a "Pushpin", as well as a "Pushpin" operating system supporting mobile computational processes are treated in detail. Example applications and future work are discussed. / by Joshua Harlan Lifton. / S.M.