scholarly journals Surrogate measures for evaluating new signage and intersection designs

2016 ◽  
Author(s):  
◽  
Zhongyuan Zhu

Transportation agencies faced with the challenge of enhancing safety on roadways are looking for alternative solutions to designing roads and signage. When deciding whether the alternative design is superior to the traditional one, decision makers need methods and quantitative data to evaluate these alternatives. This dissertation provides two accessible methods to compare different alternative designs and illustrates them using case studies. The first method involves using speed-based statistical measures that are extracted from video-based traffic surveillance. This method was more accurate in collecting vehicle speeds than the speeds extracted from video-based data collection systems. It was then utilized to evaluate the effectiveness of an alternative merge sign in work zones. This alternative sign consists of an arrow pointing the merge direction and text describing the lane closure, while MUTCD sign is graphical. The case study measured driver behavior characteristics including speeds and open lane occupancies. The results indicate that open lane occupancy was higher for the test sign in comparison to the MUTCD sign upstream of the merge sign. The occupancy values at different distances between the merge sign and the taper were similar for both the test and MUTCD signs, but the test sign encouraged up to 11% more cars to be in the open lane immediately upstream of the merge sign. Passenger cars stayed in the closed lane longer, or closer to the taper, than trucks. The merging behavior of truck drivers did not vary significantly with the type of merge sign deployed in the work zone. The analysis of speed characteristics did not reveal substantial differences between the two sign configurations. The mean speeds with the MUTCD configuration were 1.3 mph and 2 mph lower than the test configuration at the merge sign and taper locations, respectively. The second method utilizes microscopic traffic simulation to evaluate alternative designs. This method is ideal for projects where video monitoring of the entire study of interest is not feasible. Evaluating alternative designs with crash data usually requires a long time span to build the facility and record crash data over at least one year after the facility has been open to traffic. In addition to that, new facility needs to be built or altered if other design features are to be tested. With microscopic simulation, the time cost for the study is greatly shortened and different design aspects can be tested in a risk-free environment. Two case studies are presented to illustrate this simulation method. The first case study involves a work zone while the second case study focuses on evaluating a J-turn intersection design. The spacing of U-turn and the inclusion of acceleration and deceleration lanes were evaluated, in the J-turn study. A simulation analysis was conducted to study the impact of different design variables on the safety of J-turns. A base simulation model was created and calibrated using field data collected in a previous Missouri Department of Transportation (MoDOT) project on J-turns. The calibrated model was then used to study various combinations of major road and minor road volumes and design variables. The simulation analysis helped develop guidance on recommended spacing for various major road and minor road volume scenarios. For all the studied scenarios, the presence of acceleration lane resulted in significantly fewer conflicts. Thus, acceleration lanes are recommended for all J-turn designs, including lower volume sites. Second, while U-turn spacing between 1000 feet and 2000 feet was found to be sufficient for low volume combinations, a spacing of at least 1500 feet and 2000 feet are recommended for medium and high volumes, respectively.

Author(s):  
Boris Claros ◽  
Zhongyuan Zhu ◽  
Praveen Edara ◽  
Carlos Sun

Owing to the J-turn’s safety effectiveness, it has become a viable alternative to replace high-crash, two-way, stop-controlled intersections on high-speed expressways. National guidance on the design of J-turns on high-speed highways is limited. What is the safety effect of spacing between the intersection and the U-turn? Under what circumstances is the provision of acceleration lanes recommended? This study answered these questions through a safety assessment on the basis of ( a) an examination of crashes that occurred at 12 J-turn sites in Missouri and ( b) a simulation-based assessment of the effect of various design variables and traffic flows. The crash review revealed the proportions of the five most frequently occurring crash types at J-turn sites: ( a) major road sideswipe (31.6%), ( b) major road rear-end (28.1%), ( c) minor road rear-end (15.8%), ( d) loss of control (14%), and ( e) merging from U-turn (10.5%). The crash rates, accounting for exposure, decreased with the increase in the spacing to the U-turn for sideswipe and rear-end crashes; J-turns with a spacing of 1,500 ft or greater experienced the lowest crash rates. The crash rates were lower for J-turn sites with acceleration lanes for minor road traffic merging onto the major road than for sites without acceleration lanes. A calibrated simulation model analysis revealed that the presence of acceleration lanes reduced conflicts for all volumes and designs, including low volumes. The simulation analysis also reinforced the crash analysis results that safety improved with an increase in spacing between the main intersection and the U-turn.


2016 ◽  
Vol 19 (03) ◽  
pp. 391-402
Author(s):  
Sunday Amoyedo ◽  
Emmanuel Ekut ◽  
Rasaki Salami ◽  
Liliana Goncalves-Ferreira ◽  
Pascal Desegaulx

Summary This paper presents case studies focused on the interpretation and integration of seismic reservoir monitoring from several fields in conventional offshore and deepwater Niger Delta. The fields are characterized by different geological settings and development-maturity stages. We show different applications varying from qualitative to quantitative use of time-lapse (4D) seismic information. In the first case study, which is in shallow water, the field has specific reservoir-development challenges, simple geology, and is in phased development. On this field, 4D seismic, which was acquired several years ago, is characterized by poor seismic repeatability. Nevertheless, we show that because of improvements from seismic reprocessing, 4D seismic makes qualitative contributions to the ongoing field development. In the second case study, the field is characterized by complex geological settings. The 4D seismic is affected by overburden with strong lateral variations in velocity and steeply dipping structure (up to 40°). Prestack-depth-imaging (PSDM) 4D seismic is used in a more-qualitative manner to monitor gas injection, validate the geologic/reservoir models, optimize infill injector placement, and consequently, enhance field-development economics. The third case study presents a deep offshore field characterized by a complex depositional system for some reservoirs. In this example, good 4D-seismic repeatability (sum of source- and receiver-placement differences between surveys, dS+dR) is achieved, leading to an increased quantitative use of 4D monitoring for the assessment of sand/sand communication, mapping of oil/water (OWC) front, pressure evolution, and dynamic calibration of petro-elastic model (PEM), and also as a seismic-based production-logging tool. In addition, 4D seismic is used to update seismic interpretation, provide a better understanding of internal architecture of the reservoirs units, and, thereby, yield a more-robust reservoir model. The 4D seismic in this field is a key tool for field-development optimization and reservoir management. The last case study illustrates the need for seismic-feasibility studies to detect 4D responses related to production. In addition to assessing the impact of the field environment on the 4D- seismic signal, these studies also help in choosing the optimum seismic-survey type, design, and acquisition parameters. These studies would possibly lead to the adoption of new technologies such as broad-band streamer or nodes acquisition in the near future.


Author(s):  
Michelle M. Mekker ◽  
Yun-Jou Lin ◽  
Magdy K. I. Elbahnasawy ◽  
Tamer S. A. Shamseldin ◽  
Howell Li ◽  
...  

Extensive literature exists regarding recommendations for lane widths, merging tapers, and work zone geometry to provide safe and efficient traffic operations. However, it is often infeasible or unsafe for inspectors to check these geometric features in a freeway work zone. This paper discusses the integration of LiDAR (Light Detection And Ranging)-generated geometric data with connected vehicle speed data to evaluate the impact of work zone geometry on traffic operations. Connected vehicle speed data can be used at both a system-wide (statewide) or segment-level view to identify periods of congestion and queueing. Examples of regional trends, localized incidents, and recurring bottlenecks are shown in the data in this paper. A LiDAR-mounted vehicle was deployed to a variety of work zones where recurring bottlenecks were identified to collect geometric data. In total, 350 directional miles were covered, resulting in approximately 360 GB of data. Two case studies, where geometric anomalies were identified, are discussed in this paper: a short segment with a narrow lane width of 10–10.5 feet and a merging taper that was about 200 feet shorter than recommended by the Manual on Uniform Traffic Control Devices. In both case studies, these work zone features did not conform to project specifications but were difficult to assess safely by an inspector in the field because of the high volume of traffic. The paper concludes by recommending the use of connected vehicle data to systematically identify work zones with recurring congestion and the use of LiDAR to assess work zone geometrics.


2020 ◽  
Author(s):  
Shuchih Ernest Chang ◽  
YiChian Chen

BACKGROUND Blockchain technology is leveraging its innovative potential in various sectors and its transformation of business-related processes has drawn much attention. Topics of research interest have focused on medical and health care applications, while research implications have generally concluded in system design, literature reviews, and case studies. However, a general overview and knowledge about the impact on the health care ecosystem is limited. OBJECTIVE This paper explores a potential paradigm shift and ecosystem evolution in health care utilizing blockchain technology. METHODS A literature review with a case study on a pioneering initiative was conducted. With a systematic life cycle analysis, this study sheds light on the evolutionary development of blockchain in health care scenarios and its interactive relationship among stakeholders. RESULTS Four stages—birth, expansion, leadership, and self-renewal or death—in the life cycle of the business ecosystem were explored to elucidate the evolving trajectories of blockchain-based health care implementation. Focused impacts on the traditional health care industry are highlighted within each stage to further support the potential health care paradigm shift in the future. CONCLUSIONS This paper enriches the existing body of literature in this field by illustrating the potential of blockchain in fulfilling stakeholders’ needs and elucidating the phenomenon of coevolution within the health care ecosystem. Blockchain not only catalyzes the interactions among players but also facilitates the formation of the ecosystem life cycle. The collaborative network linked by blockchain may play a critical role on value creation, transfer, and sharing among the health care community. Future efforts may focus on empirical or case studies to validate the proposed evolution of the health care ecosystem.


2019 ◽  
Vol 26 (5) ◽  
pp. 669-690
Author(s):  
Federico M Mucciarelli

This work addresses the impact of language diversity and nation-specific doctrinal structures on harmonized company law in the EU. With this aim, two emblematic case studies will be analysed. The first case study is related to the definition of ‘merger’ adopted in the Company Law Directive 2017/1132 (originally in the Third Company Law Directive and the Cross-Border Merger Directive); by relying on the example of the SEVIC case decided by the Court of Justice of the European Union (CJEU), it will be shown that scholars’ and courts’ conception of the definition of ‘merger’ varies according to own domestic doctrinal structures. The second case study is related to the notion of ‘registered office’, which is key for establishing the scope of several harmonizing provisions and the freedom of establishment; this paper analyses terminological fluctuations across language versions of EU legislation and the impact of domestic taxonomies and legal debates upon the interpretation of these notions. These case studies show that company law concepts, despite their highly technical nature, are influenced by discourse constructions conducted within national interpretative communities, and by the language used to draft statutory instruments and discuss legal issues. The task of the CJEU is to counterbalance these local tendencies, and yet it is unlikely that doctrinal structures, rooted in national languages and legal cultures, will disappear.


2020 ◽  
Vol 41 (4/5) ◽  
pp. 279-293 ◽  
Author(s):  
Małgorzata Fedorowicz-Kruszewska

PurposeThe purpose of this paper is to explain the concepts related to environmental education in the context of sustainable development, to indicate the links between them as well as to identify and organize elements of library activities that have the potential to implement environmental education.Design/methodology/approachThe method of analysis and criticism of scientific and professional literature and research reports was used. The multiple case study method was also used.FindingsAn analysis of literature and multiple case studies confirms the assumption that sustainable development is now a new paradigm of librarianship. Among the goals of sustainable development are environmental goals, which in libraries can be achieved through environmental education. A broad approach to environmental education has been proposed, which is implemented not only by using library services but also by building green collections, contacts with environmentally involved librarians, using ecological library infrastructure, observing sustainable management methods in libraries, cooperation between the library and the external environment in terms of the natural environment.Research limitations/implicationsAn analysis of 20 case studies was carried out regarding the implementation of pro-environmental measures in libraries. Examination of a larger number of case studies would probably give a more complete picture of this area of activity in libraries. The next stage of research should be the development of standards/guidelines in the field of environmental education in libraries, and then the development of methods and techniques for assessing the quality of library activities in this area and methods for assessing the impact of libraries on society and the environment in the field of environmental education.Practical implicationsThe paper indicates – based on case study analyses – those library elements that have potential in the field of environmental education. They were ordered in categories that were assigned to the three main components of a library: people, artefacts and processes.Social implicationsSustainable development is a new library paradigm. The paper focuses on the environmental area, specifically environmental education. It has been recognized that libraries have considerable potential for environmental education and should be seen as socially responsible organizations that take responsibility for the impact of their decisions and actions on society and the environment.Originality/valueThe paper explains the basic concepts of environmental education and the relationships between them. It defines the area of environmental education in libraries in terms of library activity elements that can be used to organize them according to the three main components of a library, which are people, artefacts and processes. The paper also indicates that sustainable development should be treated as a new paradigm of librarianship, and environmental education as a new research field of library and information science.


2012 ◽  
Vol 7 (1) ◽  
pp. 37-44 ◽  
Author(s):  
John Greenwood

The Building Code of Australia (BCA) is the principal code under which building approvals in Australia are assessed. The BCA adopted performance-based solutions for building approvals in 1996. Performance-based codes are based upon a set of explicit objectives, stated in terms of a hierarchy of requirements beginning with key general objectives. With this in mind, the research presented in this paper aims to analyse the impact of the introduction of the performance-based code within Western Australia to gauge the effect and usefulness of alternative design solutions in commercial construction using a case study project. The research revealed that there are several advantages to the use of alternative designs and that all parties, in general, are in favour of the performance-based building code of Australia. It is suggested that change in the assessment process to streamline the alternative design path is needed for the greater use of the performance-based alternative. With appropriate quality control measures, minor variations to the deemed-to-satisfy provisions could easily be managed by the current and future building surveying profession.


2016 ◽  
Vol 118 (5) ◽  
Author(s):  
Blake E. Angelo ◽  
Becca B.R. Jablonski ◽  
Dawn Thilmany

Purpose A body of literature and case studies has developed as part of the reporting, outreach and evaluation of the local and regional food system projects supported by grants and other funders. Yet, there is concern that food value chains are promoted without adequately evaluating the viability of these businesses, or how these markets affect the performance and welfare of key stakeholders: farm vendors and local communities/economies. Design/methodology/approach This paper reviews and summarizes a comprehensive set of U.S.-based case studies focused on food value chains. We conduct a meta-analysis to systematically capture what available case study evidence tells us about: 1) trends in the viability of food value chain businesses; 2) the impact of these businesses on participating farm vendors; and, 3) the associated community economic development outcomes (framed in terms of ‘wealth creation’). Findings In addition to sharing findings from the meta-analysis, we demonstrate how the lack of standardized protocols for case study development is a barrier to learning about metric comparisons, best practices, and what impacts these food value chain businesses may have. We conclude with some recommendations of how the field can move forward to evaluate and share lessons learned using more uniform, project-driven case study development. Originality/value This is the first study to conduct a systematic meta-analysis of U.S. food value chain businesses.


1989 ◽  
Vol 3 (1) ◽  
pp. 48-62
Author(s):  
Robert J. Rotella ◽  
Douglas S. Newburg

Some athletes who are benched may experience identity crises, the impact of which may be long-lasting and far-reaching for them. Case-study interviews with three athletes who have experienced such crises are presented. The similarities in the case studies suggest that the bench/identity crisis may be a relatively common phenomenon. Suggestions are offered for athletes, coaches, and sport psychology consultants to help respond to such experiences effectively.


2008 ◽  
Vol 1139 ◽  
Author(s):  
Jack Martin

AbstractMinimizing risk is an important factor in new product planning because high volume breakthrough products require tens of millions of dollars to develop and bring to market. Sometimes risk can be minimized by following the IC model: build new devices on an existing process – just change the mask set. This approach obviously has limits. Adoption of new materials and processes greatly expands the horizon for “disruptive” products. This paper uses a case study approach to examine how changes in masks, materials and unit processes were used, and will continue to be used, to produce MEMS products for high volume applications.


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