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Using Volunteer Tracking Information for Activity-Based Travel Demand Modeling and Finding Dynamic Interaction-Based Joint-Activity OpportunitiesXu, Yitu 01 May 2011 (has links)
Technology used for real-time locating is being used to identify and track the movements of individuals in real time. With the increased use of mobile technology by individuals, we are now able to explore more potential interactions between people and their living environment using real-time tracking and communication technologies.
One of the potentials that has hardly been taken advantage of is to use cell phone tracking information for activity-based transportation study. Using GPS-embedded smart phones, it is convenient to continuously record our trajectories in a day with little information loss. As smart phones get cheaper and hence attract more users, the potential information source for self-tracking data is pervasive. This study provides a cell phone plus web method that collects volunteer cell phone tracking data and uses an algorithm to identify the allocation of activities and traveling in space and time. It also provides a step that incorporates user-participated prompted recall attribute identification (travel modes and activity types) which supplements the data preparation for activity-based travel demand modeling.
Besides volunteered geospatial information collection, cell phone users’ real-time locations are often collected by service providers such as Apple, AT&T and many other third-party companies. This location data has been used in turn to boost new location-based services. However, few applications have been seen to address dynamic human interactions and spatio-temporal constraints of activities. This study sets up a framework for a new kind of location-based service that finds joint-activity opportunities for multiple individuals, and demonstrates its feasibility using a spatio-temporal GIS approach.
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Prototyping inom ABC och BSc. : Erfarenheter från aktionsforskning i tre organisationerLarsson, Rolf G January 2004 (has links)
This dissertation focuses on how to use prototyping as a method for developing models in Management Accounting and Control Systems, a field in Business Administration. It combines three emerging theories: prototyping, Activity Based Costing (ABC) and the Balanced Scorecard (BSc). Prototyping is an alternative to the traditional systems development method. In prototyping end-users play an important role in being a part of the development team in the design of models for ABC and BSc. The study is conducted as action research projects. Together with controllers and their co-workers, in three organisations, I am engaged in four prototyping projects between 1988 and 2003. The cases are Gunnebo Fastening, Kinnarps Office Furniture and the local community organisation for Childcare & School in Västervik. The main result is that we can show that it is possible to develop models for ABC and BSc with prototyping. It is also possible to develop models for the different versions of ABC and BSc that Cooper & Kaplan and Kaplan & Norton suggest. We learn that prototyping is a process in loops consisting of four phases: exploration, experimentation, evaluation and evolution. This type of prototyping is labelled Experience based Prototyping, E-Prototyping. The contributions from the study are of two kinds. The major contribution is that with the E-Prototyping process we can see a further development of the knowledge of prototyping. In E-Prototyping I have put together various theories on prototyping into one process and identified the four phases of exploration, experimentation, evaluation and evolution. The second kind of contribution is found in models for ABC and BSc, developed with prototyping. Both ABC and BSc theories continue to be developed and I have followed that development for almost 15 years. We have been able to show, both theoretically and practically, that prototyping is an alternative to the stepwise system development method that Cooper & Kaplan and Kaplan & Norton suggest. It is a method that allows us to follow the various versions of the theory of ABC and BSc with our prototypes. We are also extending BSc theory when we use the BSc prototype Cockpit as a model for quality control and when we introduce the combination of ABC and BSc as a basis for what the C and S label value for money.
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Beyond the Active Site of the Bacterial Rhomboid Protease: Novel Interactions at the Membrane to Modulate FunctionSherratt, Allison R. 19 March 2012 (has links)
Rhomboids are unique membrane proteins that use a serine protease hydrolysis mechanism to cleave a transmembrane substrate within the lipid bilayer. This remarkable proteolytic activity is achieved by a core domain comprised of 6 transmembrane segments that form a hydrophilic cavity submerged in the membrane. In addition to this core domain, many rhomboids also possess aqueous domains of varying sizes at the N- and/or C-terminus, the sequences of which tend to be rhomboid-type specific. The functional role of these extramembranous domains is generally not well understood, although it is thought that they may be involved in regulation of rhomboid activity and specificity. While extramembranous domains may be important for rhomboid activity, they are absent in all x-ray crystal structures available. For this reason, we have focused on uncovering the structural and functional relationship between the rhomboid cytoplasmic domain and its catalytic transmembrane core.
To investigate the structure and function of the bacterial rhomboid cytoplasmic domain, full-length rhomboids from Escherichia coli and Pseudomonas aeruginosa were studied using solution nuclear magnetic resonance (NMR) spectroscopy, mutation and activity assays. The P. aeruginosa rhomboid was purified in a range of membrane-mimetic media, evaluated for its functional status in vitro and investigated for its NMR spectroscopic properties. Results from this study suggested that an activity-modulating interaction might occur between the catalytic core transmembrane domain and the cytoplasmic domain. Further investigation of this hypothesis with the E. coli rhomboid revealed that protease activity relies on a short but critical sequence N-terminal to the first transmembrane segment. This sequence was found to have a direct impact on the rhomboid active site, and should be included in future structural studies of this catalytic domain.
The structure of the cytoplasmic domain from the E. coli rhomboid was also determined by solution NMR. We found that it forms slowly-exchanging dimers through an exchange of secondary structure elements between subunits, commonly known as three-dimensional domain swapping. Beyond this rare example of domain swapping in a membrane protein extramembranous domain, we found that the rate of exchange between monomeric and dimeric states could be accelerated by transient interactions with large detergent micelles with a phosphocholine headgroup, but not by exposure to other weakly denaturing conditions. This novel example of micelle-catalyzed domain swapping interactions raises the possibility that domain swapping interactions might be induced by similar interactions in vivo. Overall, the results of this thesis have identified detergent conditions that preserve the highest level of activity for bacterial rhomboids, defined the minimal functional unit beyond what had been identified in available x-ray crystal structures, and characterized a novel micelle-catalyzed domain-swapping interaction by the cytoplasmic domain.
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Beyond the Active Site of the Bacterial Rhomboid Protease: Novel Interactions at the Membrane to Modulate FunctionSherratt, Allison R. 19 March 2012 (has links)
Rhomboids are unique membrane proteins that use a serine protease hydrolysis mechanism to cleave a transmembrane substrate within the lipid bilayer. This remarkable proteolytic activity is achieved by a core domain comprised of 6 transmembrane segments that form a hydrophilic cavity submerged in the membrane. In addition to this core domain, many rhomboids also possess aqueous domains of varying sizes at the N- and/or C-terminus, the sequences of which tend to be rhomboid-type specific. The functional role of these extramembranous domains is generally not well understood, although it is thought that they may be involved in regulation of rhomboid activity and specificity. While extramembranous domains may be important for rhomboid activity, they are absent in all x-ray crystal structures available. For this reason, we have focused on uncovering the structural and functional relationship between the rhomboid cytoplasmic domain and its catalytic transmembrane core.
To investigate the structure and function of the bacterial rhomboid cytoplasmic domain, full-length rhomboids from Escherichia coli and Pseudomonas aeruginosa were studied using solution nuclear magnetic resonance (NMR) spectroscopy, mutation and activity assays. The P. aeruginosa rhomboid was purified in a range of membrane-mimetic media, evaluated for its functional status in vitro and investigated for its NMR spectroscopic properties. Results from this study suggested that an activity-modulating interaction might occur between the catalytic core transmembrane domain and the cytoplasmic domain. Further investigation of this hypothesis with the E. coli rhomboid revealed that protease activity relies on a short but critical sequence N-terminal to the first transmembrane segment. This sequence was found to have a direct impact on the rhomboid active site, and should be included in future structural studies of this catalytic domain.
The structure of the cytoplasmic domain from the E. coli rhomboid was also determined by solution NMR. We found that it forms slowly-exchanging dimers through an exchange of secondary structure elements between subunits, commonly known as three-dimensional domain swapping. Beyond this rare example of domain swapping in a membrane protein extramembranous domain, we found that the rate of exchange between monomeric and dimeric states could be accelerated by transient interactions with large detergent micelles with a phosphocholine headgroup, but not by exposure to other weakly denaturing conditions. This novel example of micelle-catalyzed domain swapping interactions raises the possibility that domain swapping interactions might be induced by similar interactions in vivo. Overall, the results of this thesis have identified detergent conditions that preserve the highest level of activity for bacterial rhomboids, defined the minimal functional unit beyond what had been identified in available x-ray crystal structures, and characterized a novel micelle-catalyzed domain-swapping interaction by the cytoplasmic domain.
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Packaging effects on logistics activities : A study at ROL InternationalLeek, Tobias, Hassel, Johan January 2006 (has links)
Packaging has a major impact on the activities performed in a logistical value chain. Packaging can improve or decrease the efficiency of the outbound logistics process. It is therefore important to consider the activities and the value that they add to the overall process. ROL International is a Swedish store interior manufacturer that design, produce and distribute their products on a global basis. One of their basic products is the shelf concept. ROL wants to improve their efficiency and consider a change in the packaging method for the shelf concept. Two alternative packaging methods have been suggested and ROL want to know if either of the two alternatives would result in increased efficiency. The purpose of this report is to evaluate the two packaging alternatives and their impact on the activities connected to the outbound logistics at ROL International. Since the study was conducted at request from ROL International, it is considered as a qualitative single case study. Observations, mainly at ROL’s warehouse but also through an observation at one customer’s premises, were used for determination of the activities included throughout the studied process. In addition to the observations, interviews were conducted with key persons concerned with the effects of a change in packaging method. Secondary data in form of order and shelf statistics were important for the study due to its impact on the frequency in which the studied activities are performed. The study found that neither of the two suggested packaging alternatives are suitable for implementation in the present situation. This is mainly because of the increase in activities needed to perform the packaging of shelves, which would result in increased cost that cannot be justified through enhanced customer service and higher quality. More-over, the study also found that the current process for picking customer orders are ineffi-cient and might require a restructuring of the warehouse operation in order to become more efficient.
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Packaging effects on logistics activities : A study at ROL InternationalLeek, Tobias, Hassel, Johan January 2006 (has links)
<p>Packaging has a major impact on the activities performed in a logistical value chain. Packaging can improve or decrease the efficiency of the outbound logistics process. It is therefore important to consider the activities and the value that they add to the overall process. ROL International is a Swedish store interior manufacturer that design, produce and distribute their products on a global basis. One of their basic products is the shelf concept. ROL wants to improve their efficiency and consider a change in the packaging method for the shelf concept. Two alternative packaging methods have been suggested and ROL want to know if either of the two alternatives would result in increased efficiency.</p><p>The purpose of this report is to evaluate the two packaging alternatives and their impact on the activities connected to the outbound logistics at ROL International.</p><p>Since the study was conducted at request from ROL International, it is considered as a qualitative single case study. Observations, mainly at ROL’s warehouse but also through an observation at one customer’s premises, were used for determination of the activities included throughout the studied process. In addition to the observations, interviews were conducted with key persons concerned with the effects of a change in packaging method. Secondary data in form of order and shelf statistics were important for the study due to its impact on the frequency in which the studied activities are performed.</p><p>The study found that neither of the two suggested packaging alternatives are suitable for implementation in the present situation. This is mainly because of the increase in activities needed to perform the packaging of shelves, which would result in increased cost that cannot be justified through enhanced customer service and higher quality. More-over, the study also found that the current process for picking customer orders are ineffi-cient and might require a restructuring of the warehouse operation in order to become more efficient.</p>
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The Interaction Between Urban Form and Transit TravelConcas, Sisinnio 08 November 2010 (has links)
This study presents an analytical model of the interaction between urban form and the demand for transit travel, in which residential location, transit demand, and the spatial dispersion of non-work activities are endogenously determined. In this model, travel demand is considered a derived demand brought about by the necessity to engage in out-ofhome activities whose geographical extent is affected by urban form. In a departure from the urban monocentric model, residential location is defined as a job-residence pair in an urban area in which jobs, residences, and non-work activities are dispersed. Transit demand is then determined by residential location, work trips, non-work trip chains, and goods consumption.
Theoretically derived hypotheses are empirically tested using a dataset that integrates travel and land-use data. There is evidence of a significant influence of land-use patterns on transit patronage. In turn, transit demand affects consumption and non-work travel. Although much reliance has been placed on population density as a determinant of transit demand, it is found here that population density does not have a large impact on transit demand and, moreover, that the effect decreases when residential location is endogenous. To increase transit use, urban planners have advocated a mix of residential and commercial uses in proximity to transit stations. In this study, it is found that the importance of transit-station proximity is weakened by idiosyncratic preferences for residential location. In addition, when population density and residential location are jointly endogenous, the elasticity of transit demand with respect to walking distance to a transit station decreases by about 33 percent over the case in which these variables are treated an exogenous.
The research reported here is the first empirical work that explicitly relates residential location to trip chaining in a context in which individuals jointly decide residential location and the trip chain. If is found that households living farther from work use less transit and that trip-chaining behavior explains this finding. Households living far from work engage in complex trip chains and have, on average, a more dispersed activity space, which requires reliance on more flexible modes of transportation. Therefore, reducing the spatial allocation of non-work activities and improving transit accessibility at and around subcenters would increase transit demand. Similar effects can be obtained by increasing the presence of retail locations in proximity to transit-oriented households. Although focused on transit demand, the framework can be easily generalized to study other forms of travel.
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Alternative strategies for proteomic analysis and relative protein quantitationMcQueen, Peter 01 1900 (has links)
The main approach to studying the proteome is a technique called data dependent acquisition (DDA). In DDA, peptides are analyzed by mass spectrometry to determine the protein composition of a biological isolate. However, DDA is limited in its ability to analyze the proteome, in that it only selects the most abundant ions for analysis, and different protein identifications can result even if the same sample is analyzed multiple times in succession. Data independent acquisition (DIA) is a newly developed method that should be able to solve these limitations and improve our ability to analyze the proteome. We used an implementation of DIA (SWATH) to perform relative protein quantitation in the model bacterial system, Clostridium stercorarium, using two different carbohydrate sources, and found that it was able to provide precise quantitation of proteins and was overall more consistent in its ability to identify components of the proteome than DDA.
Relative quantitation of proteins is an important method that can determine which proteins are important to a biochemical process of interest. How we determine which proteins are differentially regulated between different conditions is an important question in proteomic analysis. We developed a new approach to analyzing differential protein expression using variation between biological replicates to determine which proteins are being differentially regulated between two conditions. This analysis showed that a large proportion of proteins identified by quantitative proteomic analysis can be differentially regulated and that these proteins are in fact related to biological processes.
Analyzing changes in protein expression is a useful tool that can pinpoint many key processes in biological systems. However, these techniques fail to take into account that enzyme activity is regulated by other factors than controlling their level of expression. Activity based protein profiling (ABPP) is a method that can determine the activity state of an enzyme in whole cell proteomes. We found that enzyme activity can change in response to a number of different conditions and that these changes do not always correspond with compositional changes. Mass spectrometry techniques were also used to identify serine hydrolases and characterize their expression in this organism. / February 2016
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On integrating models of household vehicle ownership, composition, and evolution with activity based travel modelsPaleti Ravi Venkata Durga, Rajesh 30 January 2013 (has links)
Activity-based travel demand model systems are increasingly being deployed to microsimulate daily activity-travel patterns of individuals. However, a critical dimension that is often missed in these models is that of vehicle type choice. The current dissertation addresses this issue head-on and contributes to the field of transportation planning in three major ways. First, this research develops a comprehensive vehicle micro-simulation framework that incorporates state-of-the-art household vehicle type choice, usage, and evolution models. The novelty of the framework developed is that it accommodates all the dimensions characterizing vehicle fleet/usage decisions, as well as accommodates all dimensions of vehicle transactions (i.e., fleet evolution) over time. The models estimated are multiple discrete-continuous models (vehicle type being the discrete component and vehicle mileage being the continuous component) and spatial discrete choice models that explicitly accommodate for multiple vehicle ownership and spatial interactions among households. More importantly, the vehicle fleet simulator developed in this study can be easily integrated within an activity-based microsimulation framework.
Second, the vehicle fleet evolution and composition models developed in this dissertation are used to predict the vehicle fleet characteristics, annual mileage, and the associated fuel consumption and green-house gas (GHG) emissions for future years as a function of the built environment, demographics, fuel and related technology, and policy scenarios. This exercise contributes in substantial ways to the identification of promising strategies to increase the penetration of alternative-fuel vehicles and fuel-efficient vehicles, reduce energy consumption, and reduce greenhouse gas emissions.
Lastly, this research captures several complex interactions between vehicle ownership, location, and activity-travel decisions of individuals by estimating 1) a joint tour-based model of tour complexity, passenger accompaniment, vehicle type choice, and tour length, and 2) an integrated model of residential location, work location, vehicle ownership, and commute tour characteristics. The methodology used for estimating these models allows the specification and estimation of multi-dimensional choice model systems covering a wide spectrum of dependent variable types (including multinomial, ordinal, count, and continuous) and may be viewed as a major advance with the potential to lead to redefine the way activity-based travel model systems are structured and implemented. / text
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Assessment of environmental management accounting at Tshwane University of TechnologyAmbe, Queen Ntombikayise. January 2011 (has links)
M.Tech. Business Administration. Business School. / Despite the growing concern of environmental issues including climate change and green
house gas emissions as demonstrated in a number of global conventions such as the
recently concluded climate change conference in Copenhagen Denmark in December
2009, little attention has been paid to how the service sector impacts the environment and
how related environmental costs are accounted for. Conversely, there is a general lack of
consideration given to environmental impacts, environmental responsibility,
accountability, environmental costs and potential cost savings within university settings.
The overall objective of the study is to assess the application of environmental
management accounting (EMA) at Tshwane University of Technology (TUT). This was
achieved by investigating the environmental impacts associated with the operations of
TUT as a service organization and examine how the institution manages, account and
report environmental cost.
The study employed a case study and data was collected by means of exploratory and
explanatory research techniques using two data sets; documentary and in-depth individual
face-to-face interviews employing a semi-structured questionnaire with closed and open
ended questions to collect primary data. Fourteen interviews were conducted with
personnel of two main divisions involved with EMA related information Building and
Estate and Finance. Documentary and interview data was transcribed and reduced through
descriptive statistics and a process of selection, focusing, simplification, abstraction and
transformation of the data enabling categories, themes and patterns to be identified.
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The results indicate that; the implementation of EMA and general governance for
environmental responsibility and accountability is extremely weak. The potential use of
EMA is neglected and, as such, EMA implementation is not considered a priority. Three
barriers to the adoption of EMA within TUT were identified as: institutional pressures, a
low profile of accounting for the environment, and management’s attitudes. There is a need
to improve the quality of information by restructuring the classification in the income and
expenditure report and introducing further classifications. Such classifications should relate
to responsibility centres. There is further need to create incentives geared to promote
environmental awareness and behavior change and to monitor non-financial information on
resources used especially electricity, water, fuel and paper to facilitate the implementation
of EMA at TUT. A general ledger model and action plan for the implementation of EMA
at TUT utilizing the use of activity based costing has been suggested.
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