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Regional Energy Simulation Methods: Identifying, Evaluating, and Comparing Methods to Support the Generation of Virtual Building Stocks at the Sub-National Level
No full textIn the United States, buildings account for approximately 40% of primary energy use and 75% of electrical energy use on an annual basis (U.S. Department of Energy 2017), making them an important target for energy reduction. However, it is believed that the rate at which building energy is being reduced could be improved. The energy efficiency gap is a hypothetical phenomenon which identifies that the reduction of building energy consumption may be occurring more slowly than possible due to a number of market barriers (Jaffe and Stavins 1994). While a number of top-down or disaggregative approaches and tools, such as Scout (Harris, et al. 2016), have been developed in an attempt to promote energy conservation measure (ECM) adoption in buildings and reduce the energy efficiency gap, it is posed that bottom-up approaches may enable more rapid change (Koopmans and Willem te Velde 2001). However, bottom-up approaches rely heavily upon the use of virtual building stocks: databases or information sets representing a set of actual buildings or variations of actual buildings in order to investigate topics such as energy consumption, waste production, or building energy demand (Kohler and Hassler 2002). Unfortunately, virtual building stocks are difficult to develop due to a lack of openly-available, comprehensive data. Furthermore, virtual building stocks are considered computationally costly and time consuming to execute since building performance simulation (BPS) is required to estimate the complex interactions associated with ECM implementation and the heat replacement effect (Wittchen and Aggerholm 2000) on these virtual building stocks. To overcome the lack of characterization data and computational cost, a number of shortcuts have been developed: the use of representative energy models (REMs), reduced order methods (RMs), and heuristic ECM search methods. As opposed to a single building energy model (SBEM) which is a single model representing a single building, a representative energy model (REM) is a single model representing two or more buildings, reducing relative computational costs but potentially incorporating prediction error. RMs such as log-addition (Surana, et al. 2012) are more rapid surrogates for BPS, but they have not been proven to reliably and accurately predict energy savings relative to BPS. While heuristic ECM search methods can be intelligent and efficient replacements for exhaustive enumeration, ensuring they identify global optimal solution sets can be challenging (De Jong 2007). It is unclear from literature how these shortcuts contribute to the market barrier of imperfect information, and what level of uncertainty they generate when used in bottomup approaches. This dissertation reviewed existing surrogates for BPS and identified a new reduced order method for predicting the energy savings of combinations of ECMs. Termed the log-additive decomposition (LAD) method, it was benchmarked against existing reduced order methods proposed in literature in a testbed representing medium offices in the Greater Philadelphia Region. The testbed utilized two REMs based on CoStar data (CoStar Realty 2012), seventy ECMs, and was built around jEPlus (Y. Zhang 2012). Conducting an exhaustive enumeration via BPS for all possible ECM combinations, which consists of 57,286,656 possible combinations, would require multiple years to simulate. In place of conducting an exhaustive enumeration, LAD was compared to BPS for all possible two-way ECM interactions and a more manageable 30,000, randomly selected ECM combinations. Results indicated that LAD requires 0.018% of the computational cost of a typical BPS (EnergyPlus) but has average prediction error in the range of 10%, a large improvement over other methods which have average errors in the range of 20% - 50%. Utilizing the same testbed to refine and hone the LAD method, LAD was used in a hybrid ECM search method and compared to an ad-hoc ECM search method (commonly used in practice), based on professional judgment (Wen, et al. 2013), and a heuristic ECM search method (commonly used in research), using jEPlus+EA (Y. Zhang 2018). Since exhaustive enumeration was not possible, the ECM search methods were compared in a permutation space where the global optimal solution was unknown. Using both identified performance assessment metrics (Knowles, Thiele and Zitzler 2006) and new metrics, results indicated that the ad-hoc ECM search method results in highly sub-optimal results. Alternately, the LAD and heuristic ECM search methods performed well with similar results. Overall, a hybrid ECM search method using LAD performed well, providing consistent results, and overcoming the knowledge required with applying and tuning optimization parameters (De Jong 2007). Following refinement and verification of the LAD method, this method was implemented in a new testbed to quantify the impact of using REMs, instead of SBEMs, on projected regional retrofit costs, projected regional energy savings, and differences in ECMs identified as cost-effective for the geography under evaluation. Using combined geospatial data (PASDA 2017) and ENERGY STAR(r) data (U.S. EPA and U.S. DOE 2018), eighty-five SBEMs and two REMs identified based on TwoStep clustering (IBM 2012) were generated and simulated in CityBES (Chen, Hong and Piette 2017) in conjunction with a library of thirty ECMs. Simulation of the cost-effective ECM curves identified for the two REMs with LAD indicated LAD prediction error was on average less than 1%, with a maximum error less than 4%. Statistical comparison of the cost-effective curve shapes generated using LAD identified that REMs may not serve as good approximations for their SBEM constituents. Furthermore, the ECMs identified and ECMs prevalent along the REM costeffective curves were also found to differ statistically from their SBEM constituents. However, it was unclear if these statistical differences in cost-effective curves would result in quantifiable differences in regional retrofit costs and regional energy savings when the virtual building stocks were used to estimate ECM package adoption across the region. To understand if the differences between the REM and SBEM-based virtual building stocks resulted in quantifiable differences for regional retrofit costs and regional retrofit savings, adoption models that were based on simple payback period (SPP) and gathered from stakeholder surveys (Hamilton 2013) were utilized to simulate stakeholder adoption of ECM packages in the region. A Monte Carlo process was used to estimate ECM package adoption for the virtual building stocks and was repeated 10,000 times to develop estimated distributions of aggregate retrofit cost, aggregate energy cost savings, and resulting SPP for the REM-based and SBEM-based virtual building stocks. Overall, results indicate that a REM-based approach may not adequately reflect actual building stakeholder decisions. In this dissertation specifically, a REM-based approach significantly underpredicts not only aggregate retrofit costs, but more importantly, aggregate retrofit savings. From this thesis, the LAD method has been benchmarked as an alternative to BPS to estimate the energy savings of combinations of ECMs. When used to support ECM searches and optimization, LAD could be considered more rapid and exhaustive than other existing reduced order methods but may introduce prediction error on the order of 10% relative to BPS. When used to support the comparison of an REM-based virtual building stock against an SBEM-based virtual building stock, results indicate that the common shortcut of using REMs is that it may not adequately represent decisionmaking and ECM adoption at the individual building level. As a result, using REMs together with ad-hoc or heuristic ECM search methods to inform policies and guidelines may be resulting in imperfect information that does not reflect actual ECM attractiveness and adoption at the individual building level. However, it is important to acknowledge that the results presented in this dissertation are just the beginning of an exploration. Additional investigation is needed to validate the methods in this dissertation and their findings. While the LAD method has enabled the generation of these preliminary results, future work needs to assess how virtual building stock development can be improved in all stages, including: documenting better building characterization data, improving and testing clustering strategies, and quantifying how results and conclusions change with improved energy model generation procedures. In the end, results indicate that current practices due confirm the notion that an energy efficiency gap exists, but a continuation to refine and implement the methods presented in this thesis could reduce the size of such a gap.Ph.D., Architectural Engineering -- Drexel University, 201
Low-Voltage Electrophoretic Deposition of Nanocrystal-Based Copper-Chalcogenide Thin-Films
No full textPhotovoltaic (PV) devices are a clean and renewable source of energy, yet their widespread adoption is hindered by their cost, much of which is dominated by fabrication of the devices themselves. Current methods for PV device fabrication are slow and energy intensive. While much work has been done to engineer solution-processable precursors to thin-film electronic materials, particularly for PV applications, relatively little has been done in developing scalable methods for depositing these "inks". In this work, electrophoretic deposition (EPD) of colloidal nanocrystals (NCs) is explored as a method for the fabrication of semiconducting thin films. For photovoltaic applications, a low process voltage is highly desirable to avoid damaging the accreting semiconductor. Herein is reported a continuous flow reactor design that can operate at reduced voltage compared to a traditional batch reactor while preserving the electrophoretic velocity of the NCs by utilizing narrow electrode spacing and removing film thickness limitations by continuously flowing the colloidal dispersion of NCs. Through modeling and experiment, the process parameters necessary to completely utilize the NCs in the feed solution, thereby achieving nearly 100% atom economy in the deposition process, are demonstrated. For electrophoretic deposition (EPD) to achieve its potential as a method for assembling functional semiconductors, however, it is necessary to understand both what governs the threshold voltage for deposition and how to reduce that threshold. Post-synthetic modification of the surface chemistry of all-inorganic copper-zinc-tin-sulfide (CZTS) nanocrystals (NCs) enables EPD at voltages below 2V--a six-fold or greater improvement over previous examples of non-oxide semiconductors. The chemical exchange of the original surfactant-based NC-surface ligands with selenide ions yields essentially bare, highly surface-charged NCs. Thus, both the electrophoretic mobility and electrochemical reactivity of these particles are increased, favoring deposition, resulting in thick, uniform and crack-free films without sintering from stable, well-dispersed colloidal starting materials. In-situ imaging of the reactor during deposition provides a quantitative measure of the electric field in the bulk of the reactor; this, coupled with chronoamperometry, reveals the fundamental reaction and mass transport limitations of low-voltage EPD, and a crossover from mass transport-limited to reaction rate-limited EPD is observed. In order to fully realize an all-solution-processed PV device, every aspect of the device must be fabricated by solution-processing methods. Consequently, solution-processed transparent conductors are also studied. 2D transition metal carbides and nitrides, known collectively as MXenes, are highly conductive and water-dispersible, suggesting their utility as solution-assembled optoelectronic and plasmonic materials. Here, 2D Ti3C2 is assembled from solution into optical quality, nanometers-thin films that, at 6500 Siemens-per-centimeter, surpass the conductivity of other solution-processed 2D materials due to their metal-like free-electron densities. Simultaneously they transmit >97% of visible light per-nanometer-thickness, constituting the first example of a new class of solution-processed, carbide-based 2D optoelectronic materials.Ph.D., Chemical Engineering -- Drexel University, 201
Alternative Diagnostic Technique of Equine Laminitis Utilizing Eccentricity of the P3 Bone in the Dorso-Ventral Radiograph
Get PDFThe horse hoof has evolved from the same appendage that now makes up the human middle finger, to bear up to 100% of a 500-kg animal, while taking up an area of less than only .05 m2. To meet these exceptionally high mechanical demands, the most distal bone (P3) is suspended in the hoof capsule through a remarkable adaptation of lamina tissue (in humans, this is the tissue underneath a fingernail). The P3 bone is encapsulated by the keratinous hoof (fingernail) in direct contact with the ground and the external environment. The lamina tissue is built to hold the bone so that the P3 bone "floats" within the hoof, providing cushion and impact dampening. When the lamina tissue begins to fail due to sickness, obesity, or age, the developed condition is referred to as laminitis, which causes the P3 bone to rotate downwards. The clinical impact of laminitis is pain, damage to the laminar tissue, and possible humane euthanasia. To diagnose laminitis, veterinarians currently take three radiographs of the horse hoof: from the lateral, ventral, and caudal views. The angle of the bone from the hoof wall in the lateral view is commonly used to diagnosis laminitis. In a healthy animal, this angle would be close to 0 and, in a horse with laminitis, this angle would be much larger. Typically, the other two views are mainly used to determine the overall health of the P3 bone, rather than to help diagnose laminitis. This limits the diagnostic ability of the veterinarian in the case of incomplete, missing, or inconclusive lateral radiographs. The goal of this study therefore was to develop an alternative method of diagnosing laminitis utilizing the ventral radiograph. It was hypothesized that the downward rotation of the P3 bone (as seen in the lateral view) would affect the shape of the P3 bone in the ventral radiograph. More specifically, if the change in the shape of the P3 bone in the ventral radiograph could be measured using the eccentricity of the bone, the ratio of the areas of the P3 bone to hoof, or the difference between the hoof and bone. These measurements were examined to determine if there was statistically significant difference between the healthy and pathological radiographs. The overall goal was divided into two aims: 1) determine if analysis of ventral view images could detect differences in known laminitis and healthy images, and 2) validate the new procedure. In the first aim, 15 sets of radiographs were studied from known cases, of which 7 subjects were diagnosed with laminitis and 8 were confirmed healthy. The angle of the bone from the hoof wall, the areas of the bone and hoof, and eccentricity of the bone were calculated for each case using custom written Matlab programs. It was determined, through statistical testing such as F-tests and 2-way ANOVAs, that eccentricity was the most viable diagnosing method among the three new methods being tested. To validate this diagnostic technique and satisfy the second aim, 35 blinded sets of radiographs were measured and diagnosed with the commonly used method and this new eccentricity-based method. These diagnoses were then compared to a veterinarian's official diagnoses. It was shown, through statistical testing, that eccentricity is an accurate diagnosing technique that exceeds the conventional practice in sensitivity, specificity, false positive rates, and false negative rates.M.S., Biomedical Engineering -- Drexel University, 201
Monitoring the Adaptation to Experimental Pain Using Functional Near Infrared Spectroscopy
Get PDFBackground: Despite pain being one of the more thoroughly studied phenomena, it is still one of the more complex and least well understood. Studies of late, in particular imaging studies, have made an attempt to take individuals' subjective response to pain into consideration, while observing how their bodies respond physiologically. This has led to our lab's focus on the adaptation to pain. As adaptation is the reduction of the response to a given stimulus over time, monitoring the adaptation to experimental pain over time using functional near infrared spectroscopy shows the change in autonomic response with each additional exposure. Doing this, while also observing the change in perception to each additional exposure, can further progress the research of pain imaging, and more importantly, show how changes in physiological response and perceptive response correlate over time. Methods: In the investigations outlined in the aims of this thesis, experimental pain (the cold pressor test in a repeated-measures fashion) was used to conduct experiments in healthy subjects. In conjunction with this, the McGill Pain Questionnaire and State Trait Anxiety Inventory were employed during experimentation as well. In post experimentation analysis, multilevel modeling, linear regression and clustering were the main techniques used to understand how the pain response changes with each additional exposure to a stimulus. Results: These statistical techniques yielded results that suggest that with each additional exposure to noxious stimulus, the magnitude of a subjects' autonomic response continues to diminish. Through the measures of perception, the subjects did not show significant change with each additional exposure; although, there was a trend demonstrating that the subjects felt the pain with slightly less intensity with each additional exposure. Conclusions: From interpreting the results of the studies performed as a part of this thesis, it is evident that functional near infrared spectroscopy is a powerful enough imaging tool to monitor adaptation to repeated exposure of stimuli. To further understand how perception and autonomic response relate, more studies with a greater number of subjects will give greater understanding of the connection (or lack thereof) between the two.Ph.D., Biomedical Science -- Drexel University, 201
Influences of Family Literacy Workshops on Title 1 Students' Family Involvement in Reading - Self-Efficacy and Perception of Reading Performance: A Mixed-Methods Study
Get PDFThe purpose of this mixed-methods study was to examine the influences of family literacy workshops on family involvement, families' self-efficacy, and their perception of their children's reading performance. The participants were families of students receiving Title 1 reading service in grade 2, 3 and 4. The research questions for this study were: Do family literacy workshops influence the way families engage with their children's reading at home? Does families' participation in family literacy workshops influence their perception of their children's reading performance? Does families' participation in family literacy workshops influence their perception of their children's reading performance? This mixed-methods study gathered data using both quantitative and qualitative methods to enhance the interpretation of the data. The pre- and post- workshop surveys and workshop exit surveys were collected. A series of four workshops that focused on fluency and comprehension strategies was presented as a part of this study. Observations from the workshops and case study interviews were collected. The researcher used semi-structured interview questions to determine the influence of family literacy workshops on family engagement in their children's reading at home, their self-efficacy in ability to help their children's reading, and their perception of their children's reading performance. The integrated analysis of quantitative and qualitative data revealed three major findings: 1) participants expressed the need to partner with teachers to support successful learning experiences for their children; 2) participants described improved involvement with their children in reading support when using resources and strategies from the literacy workshops; and 3) participants perceived improved reading skills in their children after using resources and strategies from the literacy workshops. The results of this study demonstrate that a targeted, parent-focused literacy program can be effective in promoting parents' sense of confidence and competency in support of their children's reading at home. Further research is necessary to understand the connection between parents' participation in family literacy programs and children's reading skills and academic achievement. We also must strive to understand how these programs intersect with existing cultural practices, the home learning environment, and the larger community.Ed.D., Educational Leadership and Management -- Drexel University, 201
Hypocretin receptor 1 knockdown in the ventral tegmental area attenuates mesolimbic dopamine signaling and reduces motivation for cocaine
Get PDFThe hypocretin receptor 1 (HCRTr1) is a critical participant in the regulation of motivated behavior and dopamine (DA) signaling, likely through actions on the VTA. However, while hypocretin signaling appears to influence some degree of VTA activity, its ongoing neuromodulatory role remains somewhat unknown. To further examine the involvement of VTA-HCRTr1 in regulating reward and reinforcement processing, we develop a viral technique to induce long-term knockdown of HCRTr1 expression in the VTA, and measure effects on motivated behavior, DA neurotransmission, and cell activity in the nucleus accumbens (NAc). We determine that viral knockdown induces sustained downregulation of HCRTr1 specifically in VTA, without producing toxicity, and without altering the expression of proteins important for DA synthesis and transport. HCRTr1 knockdown also delays the acquisition of cocaine self-administration, and reduces the motivation to pursue cocaine reinforcers, without affecting arousal. Additionally, we observe that HCRTr1 knockdown dramatically reduces baseline dopamine release, and attenuates the effects of cocaine on DA uptake. We then targeted HCRTr1 in only dopamine-producing cells of the VTA, and determined that such knockdown reduces DA release under low doses of cocaine, while impairing the inhibition of DA uptake inhibition of high dose of cocaine, and changes the firing pattern of cells in the NAc. Together this research helps establish viral knockdown as an important experimental technique, and provides critical information for understanding how the hypocretin system regulates addictive processes.Ph.D., Neuroscience -- Drexel University, 201
Organizing & Electoral Campaigns (OEC): Assessing the Role of Planned Parenthood Votes on Voter Turnout
Get PDFThis community-based master’s project (CBMP) reports the results of the Planned Parenthood Votes’ campaign on voter turnout. The project was developed and implemented in collaboration with Planned Parenthood, and was based around the 2016 presidential election cycle. Each year, Planned Parenthood plays an advocacy role in the national election process, and in 2016 there was a key focus on the presidential race as well as congressional and state elections. There were two campaigns underway, independent expenditures and coordinated activities, to focus on different aspects of the election. There were also reasons to divide resources while being cognizant of legal issues related to funding of political work by a not-for-profit organization. Pennsylvania, and more specifically the Philadelphia area, is extremely important in most large-scale elections due to the political divide of the state. During the 2016 elections, there was a focus on the four-county area in Southeastern Pennsylvania aimed at engaging voter mobilization outreach, and particularly in marginalized communities. The focus of this project was based on four primary activities; voter registration, community outreach, phone banking and canvassing. The project’s findings suggest that there was a correlation between counties in Pennsylvania where phone banking and canvassing occurred, but a causal link cannot be definitively proven. It should be noted that limitations from this study hindered specific like the ability to reach a wider array of populations and communities. Therefore, future studies should alter their methodology to provide alternative outcomes. One recommendation for future projects of this nature would be more intentional research, planning, and engagement designed to broaden the volunteer base, demographically, and thus allow for a wider array of concerted outreach to communities of specific interest to the organization.M.P.H., Community Health and Prevention -- Drexel University, 201
Novel Therapeutic Intervention for Myocardial infarction in large animal Model
Get PDFHeart failure (HF) represents an enormous clinical problem that imposes a significant burden both to society and survivors. During a myocardial infarction, cardiomyocytes are damaged due to a lack of oxygen to the left ventricle and as a result these cells die. The dead cells are then replaced by fibrotic scar tissue that inhibits the heart from properly pumping blood to the rest of the heart. The current treatments of HF do not reverse the damage that the left ventricle experiences and as a result many people experience recurrent heart failure and sometime cardiac arrest. The field of cellular reprogramming investigates the process of direct reprogramming of endogenous cardiac fibroblasts to cardiomyocytes as a novel approach to help the heart to pump blood properly after a myocardial infarction. In this project, we used a biodegradable hyaluronic acid (HA) hydrogel to encapsulate Adeno-associated virus (AAV) 9 engineered to deliver the reporter gene green fluorescent protein (GFP) or five transcription factors (G: Gata4, M: Mef2c, T: Tbx5, M: Mesp1and M: Myocardin) in pigs' heart post-myocardial. Our method represents a unique approach to transfect cardiomyocyte cells in vivo post-myocardial infarct in pig. This study also demonstrates a cardiac functional improvement with the injection of hydrogel gel, AAV9, and selected transcription factors in the compromised area of the left ventricle. This novel method reduced the scar tissue in the compromised area of the heart compared to control.M.S., Biomedical Science -- Drexel University, 201
Implementation of New Practice in the Treatment of Acute Ischemic Stroke
Get PDFBackground: New guidelines in the treatment of acute ischemic stroke include timely recognition of stroke symptoms and evaluation for rapid treatment of stroke with IV t-PA administration and endovascular intervention. Methods: The DNP student/project coordinator led a collaborative effort to integrate the updated AHA/ASA ischemic stroke guideline through revision of the current in-house stroke algorithm; facilitation of the implementation plan; and evaluation of the implementation plan. Evaluation: The DNP student/project coordinator suggested an evaluation of the practice change through monthly discussion of algorithm fall-outs at the Stroke Committee meetings at the hospital. Significance and Implications: Implementation of this project introduced a practice change in the clinical setting for patients who experience an in-hospital stroke. Early consideration for treatment with endovascular intervention may allow for an increase in the number of patients who are eligible to receive ischemic stroke intervention, and may lead to an improvement in stroke treatment response time.D.N.P., Nursing Practice -- Drexel University, 201
Audience engagement in New York State: A comparative case study of three orchestras in western and central New York
Get PDFThe purpose of this paper is to discover what audience engagement practices are being utilized by orchestras in Western and Central New York. In the constantly changing field of orchestral audiences, orchestras need to find innovative ways to build relationships with current and potential audiences. While the large majority of classical music audiences are white and middle to upper class, that audience group is aging, causing orchestras to focus on newer audiences, particularly younger ones. This study also discusses activities that can attract the millennial age group. The conclusions reached in the study are the result of interviews with staff members that are responsible for creating marketing plans, including engagement activities and strategies. The results found were then analyzed and considered against current suggested practices. The findings from this paper will hopefully be useful to other orchestras, across the nation, in finding and developing audience engagement activities for their constituents, including in-depth musical programming, social events before and after concerts, and interactive community outreach programs.M.S., Arts Administration -- Drexel University, 201