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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
591

Are Impact Factors Comparable? Impact Factor Comparisons Across Areas of Psychology

van der Horst, Jason J. 13 March 2010 (has links) (PDF)
Journal impact factors play an increasing role in academics as a tool for evaluating faculty, research, and resource allocations. These evaluations may be effective in departments where the subject matter is reasonably unified. However, given the diversity found within the subject matter of psychology, the impact factors of journals may not be comparable across the various areas. This study compares the average impact factors across decile levels of journals from seven areas of psychology. It is found that impact factor scores are not comparable across the seven areas of psychology. This difference is more pronounced when looking at higher decile journals. Further research could be conducted to investigate differences among psychology areas using other bibliographic variables, including some of the newer indices of individual scholar productivity, such as the h-index.
592

How to bell the cat named Social Impact Measurements : Challenges and Limitations in setting up Social Impact Measurement

Singhal, Rajat, Berlinger, Nicolas January 2018 (has links)
Social Entrepreneurship and Social Enterprises are an emerging trend. An increasing number of individuals are finding ways to address a social issue through their entrepreneurial skills. As well as increasing number of corporations and investing organizations are looking for ventures that address a social issue to fulfil their social responsibility. Thus, it is increasingly becoming important for the social entrepreneurs to measure and report their impacts to society in an accurate way. This research seeks to find out the challenges faced by social entrepreneurs while setting up social impact measurements in their ventures and the solutions adopted by them. Through a series of semi‐structured interviews with successful social entrepreneurs, this research collects qualitative data that increases the knowledge in this area and contributes in a better understanding of the challenges faced by social entrepreneurs. This research found that Theory Of Change is the most commonly used method and is preferred by practitioners as it is easy to implement. The research summarises the efforts it takes to implement the measurements, recommends best practices or advice to make impact measurement easier and useful. Also, a framework is developed that can be used in setting up measurements in a social venture.
593

Impact Of Construction On Freeway Traffic Operations

Jagtap, Seema 01 January 2008 (has links)
This study provides an insight into the impact of construction activities on traffic operations. Specifically, the topic of interest for this thesis is to study the impact of construction on traffic operations for construction projects on Interstate 4 from SR 434 to John Young Parkway, from SR 528 to SR 535, and from SR 482 to SR 528. These three projects were chosen because they were the only projects on Interstate 4 where both construction data and loop detector data were available for analysis. The data was collected by examining the Florida Department of Transportation daily inspection reports which had detailed documentation of construction operations that took place. The following information was collected: date, type of construction work being performed, time, location, and direction of impact to the traveling public. These data points were cross-referenced to the loop detector stations and mile posts to collect the loop detector data and roadway geometric characteristics such as location of ramps, type of median, etc. The loop detector data (speed, volume, and occupancy) were collected and aggregated for the data analysis. The loop detector data were collected during construction, one year prior to construction, and one year after construction for comparison purposes. Logistic regression analysis under the within-stratum matched sampling framework was conducted as an exploratory analysis to see if there was a difference on the traffic impacts with and without construction. This was done by matching the variables to ensure that there were no other differences impacting the traffic operations. Logistic regression proved there was a difference in the traffic operations with and without the presence of construction. The simple model results demonstrated that speed was reduced, occupancy was increased, and volume decreased during construction. After construction, the speed and volume increased and the occupancy decreased. Linear regression and analysis of covariance were used to quantify the impact of the various construction activities on the speed, occupancy and volume. Linear regression and analysis of covariance were used to understand the impacts from the presence of roadway geometrics on freeway traffic operations during construction. Logistic regression controls the geometrics, linear regression and analysis of covariance demonstrated how the geometrics impacted the construction effects. The geometric characteristics of each area were included in this analysis. This thesis investigates construction activities and roadway geometric parameters that impact traffic freeway operations (speed, volume, and occupancy) before, during, and after construction. This research showed the impact of different types of construction operations in a highway construction widening project. This research demonstrated that construction activities have a significant impact on speed, volume, and occupancy. Different types of construction activities have more of an impact than other activities. Paving had the highest adverse impact. Agencies writing construction contracts should prohibit paving during the most highly congested times. For example, in Orlando, Florida on Interstate 4, agencies should prohibit night paving during the peak holiday seasons (such as Thanksgiving, spring breaks, Christmas, etc.) around the tourist attractions during closing times, during the peak morning hours, and during the closing times of high attendance activities, such as Halloween Horror Nights at Universal Studios when high attendance is anticipated at the theme parks. Roadway geometrics also impact the traffic operations differently, before, during, and after construction and differently during various times of the day. The information of improved roadway geometrics and faster traffic flow can be used at open houses for upcoming projects where there are many people opposed to construction projects to show how the roadway construction projects actually increase traffic flow, helping everyone to get to their destinations much faster. The impact of the traffic delays in the congested areas, such as the tourist areas on Interstate 4 during the peak traffic times could be quantified to calculate delay costs to the roadway users.
594

Effect of Low Velocity Impact on the Vibrational Behavior of a Composite Wing

De Luna, Richard M 01 March 2016 (has links) (PDF)
Impact strength is one of the most important structural properties for a designer to consider, but it is often the most difficult to quantify or measure. A major concern for composite structures in the field is the effect of foreign objects striking composites because the damage is often undetectable by visual inspection. The objective for this study was to determine the effectiveness of using dynamic testing to identify the existence of damage in a small scale composite wing design. Four different impact locations were tested with three specimens per location for a total of 12 wings manufactured. The different impact locations were over the skin, directly over the rib/spar intersection at the mid-span of the wing, directly over the middle rib, and directly over the leading edge spar. The results will be compared to a control group of wings that sustain no damage. The wing design was based on an existing model located in the Cal Poly Aerospace Composites/Structures lab. The airfoil selected was a NACA 2412 airfoil profile with a chord length of 3 inches and a wingspan of just over 8 inches. All parts cured for 7 hours at 148°F and 70 psi. The wings were each tested on a shaker-table in a cantilever position undergoing 1g (ft/s2) acceleration sinusoidal frequency sweep from 10-2000 Hz. The 1st bending mode was excited at 190 Hz and the 2nd bending mode was excited at 900 Hz. After the pre-impact vibrational testing each wing was impacted, excluding the control group. To verify the experimental results, a finite element model of the wing was created in ABAQUS. The frequency and impact numerical results and the experimental results were in good agreement with a percent error for both the 1st and 2nd mode at around 10%.
595

Using Bioretention Retrofits to Achieve the Goals of Virginia's New Stormwater Management Regulations

Buckland, Brett Andrew 25 March 2014 (has links)
Virginia's new stormwater regulations involve the use of the Runoff Reduction Method (RRM), which requires the product of the peak flow rate and runoff volume (Q*RV) from the one-year storm event in the post-development condition to be reduced to eighty percent of the pre-development Q*RV to protect against channel erosion. This study models different bioretention cell sizes in a developed watershed in Blacksburg, Virginia to determine the "performance" at both the sub-watershed and watershed levels. In addition, models of "optimal" bioretention cells sized to meet the RRM for each sub-watershed are evaluated. A direct relationship is determined between the size of the cell required to meet the RRM and the sub-watershed's Natural Resources Conservation Service (NRCS) curve number. However, the required size for some of the cells is much larger than those typically seen. With the RRM applied for all of the sub-watersheds, the resulting hydrograph at the watershed outlet has a lower peak than the pre-development condition. / Master of Science
596

Vegetated Swales in Urban Stormwater Modeling and Management

White, Kyle Wallace 29 May 2012 (has links)
Despite the runoff reduction efficiencies recommended by various regulatory agencies, minimal research exists regarding the ability of vegetated swales to simultaneously convey and reduce runoff. This study assessed the effect water quality swales distributed among upstream sub-watersheds had on watershed hydrology. The study was also posed to determine how certain design parameters can be dimensioned to increase runoff reduction according to the following modeling scenarios: base, base check dam height, minimum check dam height, maximum check dam height, minimum infiltration rate, maximum infiltration rate, minimum Manning's n, maximum Manning's n, minimum longitudinal slope, and maximum longitudinal slope. Peak flow rate, volume, and time to peak for each scenario were compared to the watershed's existing and predevelopment conditions. With respect to the existing condition, peak flow rate and volume decreased for all scenarios, and the time to peak decreased for most scenarios; the counterintuitive nature of this result was attributed to software error. Overall, the sensitivity analysis produced results contrary to the hypotheses in most cases. The cause of this result can likely be attributed to the vegetated swale design and modeling approaches producing an over designed, under constrained, and/or over discretized stormwater management practice. / Master of Science
597

Runoff Impacts And Lid Mitigation Techniques For Mansionization Based Stormwater Effects In Fairfax County, Va

Hekl, Jessica Ann 17 June 2015 (has links)
This study uses the Natural Resources Conservation Service (NRCS) TR-55 method to quantify the increase in stormwater runoff volume from infill residential redevelopment, or mansionization, in a 34-acre residential subwatershed of Fairfax County, Virginia. Analysis of 10 redeveloped lots in the subwatershed showed an average increase in impervious cover from 8% to 28% after redevelopment, resulting in an average increase in runoff volume of 18% for the 10-year, 24-hour storm. From 1997 to 2009, the total impervious cover in the subwatershed increased from 18% to 25%, resulting in a calculated 6% increase in runoff volume. Low Impact Development (LID) techniques were modeled as retrofits in the subwatershed to mitigate the increase in runoff volume. Measures modeled include bioretention basins, infiltration trenches, amended soils, permeable pavement, and cisterns. Results indicate that placing bioretention basins or infiltration trenches on 0.5% of the subwatershed or amending 20% of the open space with soil composts would reduce the runoff volume back to the 1997 quantity for the 1-year, 24-hour storm. / Master of Science
598

Bioretention Hydrologic Performance in an Urban Stormwater Network

James, Matthew Bruce 27 May 2010 (has links)
While many studies have evaluated the hydrologic effects of bioretention at the site level, few have investigated the role bioretention plays when distributed throughout a watershed. This study aims to assess bioretention's effects on an urbanized watershed using two modeled scenarios: one where runoff from many land uses was routed through the practice, and another in which only runoff from large impervious areas was routed. Peak flows, volumes, and lag times from these models were compared to the watershed's current and predeveloped conditions. Both scenarios provided reductions in peak flows with respect to existing conditions for modeled storm events, sometimes to levels below the predeveloped condition. Neither case was able to reduce volumes to predevelopment levels; the option to treat impervious areas had a negligible effect on runoff volume. Both cases were able to extend lag times from the existing development condition. Based on these results, bioretention appears to have the capability to improve watershed hydrologic characteristics. Furthermore, only treating impervious areas could be a viable alternative when funds or space are limiting factors. / Master of Science
599

Oil spill: are we doing enough to avoid it?

Pu, Jaan H. 19 April 2017 (has links)
Yes / This paper reviews the recent studies on the identification and cleaning methods, as well as the consequences of oil spill. The future progression on oil spill prevention studies are also projected here.
600

Social Performance Standards in the Impact Investing Industry : Potential Consequences for Impact Investors

Fornaziere, Felipe January 2012 (has links)
In the recent years, a new type of investments called Impact Investing has been growing rapidly. Those investments are made with the intention to improve social and/or environmental conditions in the world while generating financial returns. In this case, financial metrics are not enough to measure whether the investor objective was reached, and tools for measuring the social performance of the investments are needed. From that need, various measurement approaches were created, but the fragmentation of methods leads to a huge inefficiency in the impact investing industry. Efforts towards creating standards for measuring and reporting social performance are emerging, but there is still little  understanding among impact investors about the real benefits and possible challenges the standardization would bring. In this context, an important question arises, which is the subject of study in this research: What are the potential consequences of establishing social performance standards for the impact investing industry? The purpose of this research is to analyze the possible consequences of establishing social performance standards on the impact investing industry. Qualitative approach and interpretive paradigm were chosen to be followed in this research. Primary data was collected in the form of interviews with impact investors and specialists in social performance measurement. Secondary data comes from books, articles, journals and websites. The data was analyzed using the consequences of innovations framework presented by Rogers (2003). The results suggest that obviously there are potential desirable and undesirable direct consequences, but also indirect consequences that are not perceived without a thorough analysis.

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