혁신적인 인터체인지 도입 사례 연구

DDI (Diverging Diamond Interchange) as an improved diamond interchange type is getting increasing use across the United States, however, its operational performance and feasibility in China remains unclear. This paper, combined with Chinese traffic conditions, presents operational performance evaluation and feasibility analysis of DDIs. It proposes a mathematical methodology, which could determine the capacity and level of service of DDIs, with critical movement theories. Besides, it compares the network performance of DDIs, improved and conventional diamond interchanges in VISSIM, and analyzes the crash data to obtain the applied condition of DDIs. The results show that the critical movement based evaluation procedure is a quick and reliable method to analyze DDIs in a planning stage, and DDIs are appropriate treatments to replace domestic over-capacity diamond interchanges, especially for locations with high left-turn demands to and from the freeway.

Diverging diamond interchanges (DDIs) are an emerging interchange configuration that eliminates the need for left-turn phases in conventional diamonds and may be less expensive to construct than some alternative geometries. This paper examines signal timing for DDIs. DDI signal timing typically has used a two-phase configuration that reflects the two competing movements at the crossover points at each inter section of the DDI. This configuration inherently contains some inefficiency: (a) there is potential for internal queuing under two-phase configuration and (b) it is possible for the inflow demand to exceed outflow capacity of the interchange. This paper uses high-resolution event data to develop performance measures for evaluating operations at a DDI in Salt Lake City, Utah. Alternatives to the existing signal timing within the two-phase configuration are modeled and tested with a field deployment. The field deployment demonstrated the ability to prioritize ramp or through vehicles within the two-phase configuration. Additionally, a new three-phase configuration was developed and deployed to address the internal queuing that occurs with two-phase timing. With this new configuration, the flows from one DDI intersection to the other are balanced, and progression within the DDI is improved. With the implementation of the three-phase configuration, the percentage of vehicles arriving on green at the heaviest internal movement within the DDI increased from 53% to 92%. To illustrate these performance measures and improved DDI operation qualitatively, a video from a tethered unmanned aerial vehicle demonstrated the vehicle arrival characteristics by overlaying vehicle detection and signal state graphics on the video.

The diverging diamond interchange (DDI) is growing in popularity as an interchange treatment, yet there is rather limited guidance available on signal timing practices. One particular area of concern is the coordination of a DDI along with neighboring intersections in an arterial. This study examines three different cycle length strategies for DDI coordination: (1) using the full cycle length of the corridor; (2) using a half-cycle; and (3) using a previously described three-phase scheme intended to manage queues within the DDI. Six different origin-destination (O-D) scenarios are tested in a microsimulation study. Results are presented in terms of the number of stops, movement delays at the DDI, queue lengths, and delay by O-D path. The outcomes show that the half-cycle strategy yielded lower total and average delays yet resulted in more stops along the arterial and higher arterial O-D path delays. The full-cycle option, meanwhile, tended to achieve fewer stops and lower delays for arterial routes but increased total and average delays for other movements. The three-phase strategy often reduced delays and queue lengths for the arterial movements exiting the DDI, but increased these for other movements.

Deployments of diverging diamond interchange (DDI) have increased in recent years. Most research has focused much effort on optimizing signal timing within the DDI, but there remains a need to optimize a DDI within an existing system to ensure smooth corridor operation. This paper presents a methodology for optimizing offsets on a corridor including a single-controller DDI. This methodology uses high-resolution controller data and an enhancement to the linkpivot algorithm that deconstructs the single-controller parameters into equivalent offset adjustments. The methodology is demonstrated by its application to a 5-intersection arterial route including a DDI, and the outcomes are assessed by measurement of travel times by Bluetooth vehicle re-identification. A user benefit methodology is applied to the travel time data that considers the reliability of the travel times in addition to the central tendency. Further, the methodology is applied to origin-destination (O-D) paths that travel to and from the freeway in addition to routes along the arterial. A total annualized user benefit of approximately $564,000 was achieved. The paper concludes by discussing how the method can also be applied to other nontraditional control schemes connected to arterials, such as continuous-flow intersections and TTI four-phase diamonds.

Transportation planners and traffic engineers are facing the challenge of inventing ways to mitigate congestion during the peak hours. Alleviating delays and improving safety for passengers and pedestrians are the primary motives. One way of achieving these objectives is to search for alternative intersection and interchange designs. This paper presents the results of a study on two new alternate designs: double crossover intersection and diverging diamond interchange. These designs were studied for different traffic scenarios with the use of traffic simulation, and the results showed better performance during peak hours than that of similar corresponding conventional designs. Better performance includes better level of service, shorter delays, smaller queues, and higher throughput.

Even though diverging diamond interchanges (DDIs) have been the subject of research for more than a decade, the effort to standardize interchange signal timing has developed only recently. A three-factor fully crossed experiment was conducted to investigate the influence of crossover spacing and increased volumes on the performance of DDI phasing schemes. PTV Vistro software and the dynamic bandwidth assessment tool were used to optimize the split, cycle length, and offset of each of the 72 treatments. PTV Vissim software was used to collect microsimulation data. Mean interchange delay and mean stops per vehicle were selected as measures of effectiveness. Pairwise comparisons were used to determine whether an existing preferred phasing scheme could minimize delays or stops under three cases: ( a) given spacing and increased volume, ( b) given volume independent of spacing, and ( c) given spacing independent of increased volume. The data revealed that a two- or three-critical-movement phasing scheme usually resulted in the lowest mean interchange delay and the fewest stops. Overall, the results provide an initial signal timing scheme for practitioners given a crossover spacing, an increased volume, or both. Future work will include exploring low volumes, balanced interchange volumes, and their effects on the four-critical-movement phasing scheme, as well as the effect of closely spaced adjacent intersections.

Diverging Diamond Interchanges (DDIs) are an innovative form of grade separated interchange which have proven to deliver operational and safety benefits, as well as substantial cost savings in their successful implementation around the world. DDIs provide an opportunity to efficiently upgrade existing grade separated interchanges on the national road network through retrofitting, providing safety and operational benefits which align with evolving policy for sustainable road infrastructure development, and promoting the safe, efficient and sustainable mobility of people and goods in Ireland.

Diverging diamond interchanges (DDIs) are relatively new in the United States, and signal coordination between the crossovers and adjacent intersections is challenging. This paper provides a method for remotely fine-tuning offsets for a DDI and its adjacent intersections. The proposed method uses the dynamic bandwidth analysis tool (DBAT). The tool uses actuated phase times from the signal controller to optimize the dynamic bandwidth on the basis of that entry data set. Four performance measures evaluated the proposed method: delay, stop severity index, maximum queue, and vehicle trajectory plots. The test results confirmed that DBAT provided a better offset solution than other bandwidth optimization tools that generally optimized programmed bandwidth only and did not account for early return to green caused by skipped or gapped-out movements. Under the DBAT offsets, delay for the through movements on the corridor decreased by 52.8% for northbound vehicles and 46.83% for southbound vehicles. The average delay reduction over all measured paths for uncongested and congested scenarios was 13.88% and 3.50%, respectively. The proposed method and workflow can significantly reduce the offset retiming work process. Normally, this manual process takes more than a day, but the proposed method can be completed in less than an hour without visiting the study site. Furthermore, the proposed method can coordinate any set of movements, as well as multiple travel paths. The authors believe that the proposed method and workflow will significantly help both retiming and new timing of arterial signal coordination along DDI corridors and other signal systems.

The double crossover diamond (DCD) (also known as the diverging diamond interchange) was first introduced conceptually to engineers and planners in the United States less than a decade ago. The concept has been spreading rapidly since that time; as of July 2013, DCDs had been constructed in 19 locations in eight states and had been studied in countless other projects nationwide. Nearby frontage roads pose operational challenges for all interchanges, and DCD geometry intensifies this problem. Reverse curvature for crossover points reduces the storage length between ramps and nearby frontage roads in DCDs. The crossover roundabout concept was conceived as a potential solution to this challenge. Instead of a signalized crossover point (as in a DCD), a five-legged roundabout was proposed for the intersecting arterial, frontage road, and ramps. A crossover roundabout would function essentially like any other roundabout except that it would adjoin an arterial roadway with travel directions flipped on one side. The operational and safety benefits of typical roundabouts are expected to apply to crossover roundabouts; no new driver behaviors must be learned. Variations of crossover roundabout interchanges are possible: one crossover roundabout could adjoin half of a DCD, or two crossover roundabouts could form a complete interchange. Interchanges with two crossover roundabouts would look like typical double-roundabout diamond interchanges with the arterial road directions flipped between the roundabouts. Crossover roundabouts are not required to contain frontage roads to function. Microsimulation and cost estimations have shown the concept to have merit; crossover roundabouts can combine the best attributes of DCDs and roundabouts.

<p>[[Video(http://www.youtube.com/watch?v=B6d7xeYlAiw)]] This video shows three-phase operations featuring a hold-back phase with data characterizing the southbound internal through movement (OL-C) on May 15, 2014, at the SR-201 / Bangerter DDI in Salt Lake City, Utah. The gray dots are associated with vehicles from the upstream ramp movement (OL-H) and the black dots are associated with vehicles from the upstream external through movement (OL-E). Radar detection was used, so closely spaced vehicles often generate one detection for the group instead of a unique detection for each vehicle. Latitude/Longitude: 40.726568° / -111.9855606°</p>

In this paper we propose a method to evaluate the performance of an intersection using location traces collected from sampled vehicles. The performance is measured in terms of the times the vehicles spend traveling through the intersection. As a use case, we apply the method to conduct a before and after study for 1) two unconventional intersection projects including a continuous flow intersection (CFI) and a diverging diamond interchange (DDI), and 2) for two neighboring conventional intersections to factor out effects due to possible changes in the local traffic volume. The analysis shows that for the CFI project travel time is reduced after construction. On the other hand, we find two unexpected results: 1) for the DDI project, we observe an increase of travel time after construction and 2) for the CFI project, we find a decreased benefit during rush hours. We further translate the time reduction to economic benefit based on traffic volume and value of time to offer an understanding of ROI (Return on Investment) for the intersection modification construction costs.

This exploratory study assesses factors that harness agricultural technology adoption among smallholder farmers in Kakamega County, Kenya by evaluating the key variables that influence sustainable adoption of agricultural innovations in the area. A survey was randomly administered in June and July 2018 among smallholder farming households in seven sub-counties (N=78) of Kakamega County. A logistic regression model, capturing factors presumed to influence the adoption of agricultural innovations, was estimated. Results suggest that even in smallholder farms, the farm size is important in adoption of innovations. Results also indicate limited or no farmer interaction (55%) with extension services. Farmers reported application of fertilizer and use of push-pull technology as less important in maintaining soil health. The regression model findings suggest that variables typically presumed to influence adoption in the literature are insignificant in this case study. The statistical significance of the farm size variable implies that agricultural extension messages can be tailored to a variety of farmer audiences for suitable adoption based on farm size. The diffusion of innovation theory remains a valid and relevant framework in studying adoption. This study reiterates the critical role that farmers or their environment play in the adoption process.

As Industry 4.0 offers significant productivity improvements, its relevance has grown across various organisations. While it captures the attention of both the industry and the academia, very few efforts have been made to streamline useful indicators across stages of its implementation. Such work facilitates the development of strategies that are appropriate for a specific stage of implementation; therefore, it would be significant to a variety of stakeholders. As a result, this paper aims to establish an indicator system for adopting Industry 4.0 within the context of the three stages of the innovation adoption: (i) pre-adoption, (ii) adoption, and (iii) post-adoption. First, a comprehensive review was performed with a search expanding into the literature on innovation and technology adoption. Second, the resulting indicators were filtered for relevance, redundancy, description, and thorough focus discussions. Finally, they were categorised by their stage of adoption. From 469 innovation adoption indicators found in the literature, this work identified a total of 62 indicators relevant for the Industry 4.0 adoption, in which 11, 14, and 37 of them comprised the three stages, respectively. Case studies from two manufacturing firms in the Philippines were reported to demonstrate the applicability of the proposed indicator system. This work pioneers the establishment of an indicator system for the Industry 4.0 adoption and the classification of such indicators into three stages — pre-adoption, adoption, and post-adoption — which would serve as a framework for decision-makers, practitioners, and stakeholders in planning, strategy development, resource allocation, and performance evaluation of the Industry 4.0 adoption.

BackgroundPriority setting in health care is a challenge because demand for services exceeds available resources. The increasing demand for less invasive surgical procedures by patients, health care institutions and industry, places added pressure on surgeons to acquire the appropriate skills to adopt innovative procedures. Such innovations are often initiated and introduced by surgeons in the hospital setting. Decision-making processes for the adoption of surgical innovations in hospitals have not been well studied and a standard process for their introduction does not exist. The purpose of this study is to describe and evaluate the decision-making process for the adoption of a new technology for repair of abdominal aortic aneurysms (endovascular aneurysm repair [EVAR]) in an academic health sciences centre to better understand how decisions are made for the introduction of surgical innovations at the hospital level.MethodsA qualitative case study of the decision to adopt EVAR was conducted using a modified thematic analysis of documents and semi-structured interviews. Accountability for Reasonableness was used as a conceptual framework for fairness in priority setting processes in health care organizations.ResultsThere were two key decisions regarding EVAR: the decision to adopt the new technology in the hospital and the decision to stop hospital funding. The decision to adopt EVAR was based on perceived improved patient outcomes, safety, and the surgeons' desire to innovate. This decision involved very few stakeholders. The decision to stop funding of EVAR involved all key players and was based on criteria apparent to all those involved, including cost, evidence and hospital priorities. Limited internal communications were made prior to adopting the technology. There was no formal means to appeal the decisions made.ConclusionThe analysis yielded recommendations for improving future decisions about the adoption of surgical innovations. ese empirical findings will be used with other case studies to help develop guidelines to help decision-makers adopt surgical innovations in Canadian hospitals.

Modern technology innovations feature a successive and even recurrent procedure. Intervals between old and new generations of technology are shrinking, and the Internet and Web services have facilitated the fast adoption of an innovation even before the convergence of its predecessor. While the adoption and diffusion of innovations have been studied for decades, most theories and analyses focus on single and one-time innovations. Meanwhile, limited work has investigated successive innovations while lacking user-level analysis, possibly due to the unavailability of fine-grained adoption behavior data. In this study, we present the first large-scale analysis of the adoption of recurrent innovations in the context of mobile app updates, investigating how millions of users consume various versions of thousands of apps on their mobile devices. Our analysis reveals novel patterns of crowd and individual adoption behaviors, which suggest the need for new categories of adopters to be added on top of the Rogers model of innovation diffusion. We show that standard machine learning models are able to pick up various sources of signals to predict whether users in these different categories will adopt a new version of an app and how soon they will adopt it.