Browsing by Subject "Codes"

Now showing 1 - 4 of 4

Coding sustainable neighborhoods : a comparative analysis of LEED for neighborhood development and the healthy development measurement tool
(2012-12) Niswonger, Jean Louise Yano; Moore, Steven A., 1945-; Sletto, Bjørn I
Neighborhood design has a significant impact on environmental and human health and is largely regulated by the codes developed by various professional organizations. While the sustainability movement as a whole has embraced the mutually beneficial goals of improving environmental and human health, the work of professionals in the environmental and public health fields has remained largely segregated over the past century. The purpose of my thesis is to compare the approach of each field in fostering sustainable neighborhoods through the development and implementation of codes and to quantify both the existing degree of collaboration and the latent potential for further collaboration within these codes. For comparison, I selected LEED for Neighborhood Development and the Healthy Development Measurement Tool to be representative of neighborhood codes generated by the environmental and public health movements, respectively, because they are the most fully developed and widely implemented evaluation systems presently available in each field. In order to investigate how the codes generated in each field compare in their approach, structure, and organization, I first performed a comparative analysis between them. I then performed a content analysis on both codes to quantify the overlap in goals between them. My hypothesis was that each field would exhibit a bias towards goals which explicitly support their own field, but that a significant portion of their goals would simultaneously support the other field. This hypothesis proved to be correct, but most interesting was the significant percentage of shared goals that were left unexpressed. Ultimately, 94% of recommended actions in LEED-ND were related to human health, though it was only explicitly referenced in 25% of the code. Similarly, 74% of recommended actions in the HDMT were related to environmental health, though it was only explicitly mentioned in 33% of the code. My thesis demonstrates that, while both fields already recognize that a small portion of their goals are shared, it is actually likely that nearly all of their goals are shared. By actively acknowledging these shared goals, both fields can potentially benefit from the greater amount of support, resources, and expertise that would become available to them through collaboration.
From air-conditioning to clotheslines: dynamic conditions and the nature of energy modeling for code compliance
(2014-05) Gelfand, Samuel Noah; Moore, Steven A., 1945-
This thesis, based on a methodology borrowed from Science and Technologies Studies (STS), studies the implications of using energy modeling software for code compliance in the architectural design process. Specifically, the careful study of the development and use the of the software itself, including the assumptions and frameworks of its developers and users, is required to accurately examine the implications and practical effectiveness of using energy modeling to aid in reducing the environmental consequences of the built environment. I argue that the value in studying energy modeling software is not primarily to improve the scientific accuracy of the software. Rather, the value is to demonstrate how the assumptions used in the software’s calculation methodology can adversely influence the technological decisions made by building designers when using the software to demonstrate compliance with energy codes. To develop this hypothesis I have employed both historical and empirical methods. In my historical analysis, I find that the origins of modern building energy modeling software date back to the beginning of the air conditioning industry at the start of the 20th century. One consequence of this history is that assumptions built into the software measure the relative efficiency of building components under static and assumed average conditions, but not the dynamic rates of consumption caused by inhabitation. This, in-turn, prescribes the problem-at-hand of energy code compliance as primarily technical. However, as others have argued, dynamic social and circumstantial issues also influence energy consumption (Guy & Shove, 2000). Therefore as means to examine potential conflicts between the static and technical method of analysis employed by code compliance energy modeling software and the dynamic and circumstantial context in which buildings are designed, my empirical analysis is of a design process for a net-zero energy subdivision in Austin, Texas in which energy modeling was required and used extensively. The case study is designed to demonstrate how the problems-at-hand for each distinct group of stakeholders involved in the design process was varied and did not necessarily conform to the technical solution advocated by the energy modeling process. A primary conclusion of my analysis is that all mature technologies come to us with embedded assumptions that may subvert our intentions. A secondary conclusion is that the competing assumptions and problem definitions of building scientists and building designers tend to frustrate the goal of sustainable development. My hope in studying energy modeling, in relation to practice and code compliance, is to discover ways to better use the analytical power of energy modeling that is more directly responsive to the dynamic and contextual conditions of architectural production and real world resource consumption.
Harmonization of residential & commercial mixed-use developments : investigation of regulatory issues by case studies
(2013-08) Hsieh, Yu-Tang; Lee, Ming-Chun
Mixed-use neighborhoods, which feature increased housing/job variety and density, can create pedestrian and bicycle-friendly environments by reducing dependency on vehicles and traffic congestion, and shortening distances between housing, workplaces and other destinations. Municipal regulations are vital to modern mixed-use developments due to their capability to control the direction of metropolitan growth. In this research, I have attempted to make a correlation between local regulations and current neighborhood development patterns in three well known, mixed-use neighborhoods using the case study approach. Three mixed-use neighborhoods, the North Pearl District (NPD; Portland, Oregon), South Lake Union (SLU; Seattle, Washington) and False Creek North (FCN; Vancouver, Canada), were chosen for this case study research. I examined and visualized the local regulations that pertain to mixed-use development of each neighborhood using Illustrator and SketchUp. I also analyzed and discussed U.S. Census information, including households per acre, average household size and household vehicle occupancy. The investigation indicates that among the three neighborhoods, the mixed-use regulations of FCN are the most straightforward and clear. This is reflected in the consistency between regulations and current land uses. The overall mixed degree in NPD is relatively large likely due to its incentive regulations, making itself as a highly walkable neighborhood. The local regulations in SLU are the most complicated, and focus on attracting innovative firms. In conclusion, we have conducted a study to investigate the development of mixed-use neighborhoods by scrutinizing local regulations and analyzing current situations and statistical data. The results indicated that the straightforward and incentive regulations, such as legalized neighborhood land use plan and bonus floor area ratios, benefit the mixed-use developments of neighborhoods by increasing the efficiency in land use and maximizing the mixed-use degree, thus leading to a compact, walkable and vital community.
Lower bounds and correctness results for locally decodable codes
(2011-08) Mills, Andrew Jesse; Gál, Anna; Klivans, Adam; Plaxton, Charles G.; Vishwanath, Sriram; Zuckerman, David
We study fundamental properties of Locally Decodable Codes (LDCs). LDCs are motivated by the intuition that traditional codes do not have a good tradeoff between resistance to arbitrary error and probe complexity. For example, if you apply a traditional code on a database, the resulting codeword can be resistant to error even if a constant fraction of it was corrupted; however, to accomplish this, the decoding procedure would typically have to analyze the entire codeword. For large data sizes, this is considered computationally expensive. This may be necessary even if you are only trying to recover a single bit of the database! This motivates the concept of LDCs, which encode data in such a way that up to a constant fraction of the result could be corrupted; while the decoding procedures only need to read a sublinear, ideally constant, number of codeword bits to retrieve any bit of the input with high probability. Our most exciting contribution is an exponential lower bound on the length of three query LDCs (binary or linear) with high correctness. This is the first strong length lower bound for any kind of LDC allowing more than two queries. For LDCs allowing three or more queries, the previous best lower bound, given by Woodruff, is below [omega](n2). Currently, the best upper bound is sub-exponential, but still very large. If polynomial length constructions exist, LDCs might be useful in practice. If polynomial length constructions do not exist, LDCs are much less likely to find adoption -- the resources required to implement them for large database sizes would be prohibitive. We prove that in order to achieve just slightly higher correctness than the current best constructions, three query LDCs (binary or linear) require exponential size. We also prove several impossibility results for LDCs. It has been observed that for an LDC that withstands up to a delta fraction of error, the probability of correctness cannot be arbitrarily close to 1. However, we are the first to estimate the largest correctness probability obtainable for a given delta. We prove close to tight bounds for arbitrary numbers of queries.