Search results

Accurately estimating the severity of derailment is a crucial step in quantifying train derailment consequences and, thereby, mitigating its impacts. The purpose of this paper is to propose a simplified approach aimed at addressing this research gap by developing a physics-informed 1-D model. The model is used to simulate train dynamics through a time-stepping algorithm, incorporating derailment data after the point of derailment.

In this study, a simplified approach is adopted that applies a 1-D kinematic analysis with data obtained from various derailments. These include the length and weight of the rail cars behind the point of derailment, the train braking effects, derailment blockage forces, the grade of the track and the train rolling and aerodynamic resistance. Since train braking/blockage effects and derailment blockage forces are not always available for historical or potential train derailment, it is also necessary to fit the historical data and find optimal parameters to estimate these two variables. Using these fitted parameters, a detailed comparison can be performed between the physics-informed 1-D model and previous statistical models to predict the derailment severity.

The results show that the proposed model outperforms the Truncated Geometric model (the latest statistical model used in prior research) in estimating derailment severity. The proposed model contributes to the understanding and prevention of train derailments and hazmat release consequences, offering improved accuracy for certain scenarios and train types

This paper presents a simplified physics-informed 1-D model, which could help understand the derailment mechanism and, thus, is expected to estimate train derailment severity more accurately for certain scenarios and train types compared with the latest statistical model. The performance of the braking response and the 1-D model is verified by comparing known ride-down profiles with estimated ones. This validation process ensures that both the braking response and the 1-D model accurately represent the expected behavior.

The purpose of this paper is to present a comparative study of flight circumstances, dynamic stability characteristics and controllability for two transport aircraft in severe atmospheric turbulence at transonic cruise flight for the purpose to obtain the prevention concepts of injuries to passengers and crew members for pilot training in International Air Transport Association (IATA) – Loss of Control In-flight (LOC-I) program.

A twin-jet and a four-jet transport aircraft encountering severe atmospheric turbulence are the study cases for this paper. The nonlinear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling technique based on the flight data of flight data recorder. This method can be adopted to examine the influence of horizontal wind shear and crosswind on loss of control, dynamic stability characteristics and controllability for transport aircraft in different weights and different sizes in tracking aviation safety of existing different types of aircraft.

The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiate the sudden plunging motion during the turbulence encounter. The roll rate will increase the oscillatory rolling motion during plunging motion, if the rolling damping is insufficient. The drop-off altitude will be enlarged by the oscillatory rolling motion during the sudden plunging motion.

A lack of the measurement data of vertical wind speed sensor on board to verify the estimated values of damping term is one of the research limitations for this study. The fact or condition of being severe in sudden plunging motion can be judged through the analysis of oscillatory derivatives with both dynamic stability and damping terms.

The roll rate will increase the oscillatory rolling motion during plunging motion, if the rolling damping is insufficient. The drop-off altitude will be enlarged by the oscillatory rolling motion during the sudden plunging motion. The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiated the sudden plunging motion during the turbulence encounter. If the drift angle is large, to turn off the autopilot of yaw control first and stabilize the rudder by the pedal. When passing through the atmosphere turbulence area, the pilots do not need to amend the heading angle urgently.

The flight safety prevention in avoidance of injuries for passengers and cabin crews is essential for the airlines. The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiated the sudden plunging motion during the turbulence encounter.

The flight safety prevention in avoidance of injuries for passengers and cabin crews is essential. The present assessment method is an innovation to examine the loss of control problems of aviation safety and promote the understanding of aerodynamic responses of the jet transport aircraft. It is expected to provide a valuable lecture for the international training courses for IATA – LOC-I program after this paper is being published.

The technical report released by the National Transportation Safety Board, along with the primary flight cockpit voice recorder data and archival interview data, were used as the basis for this case. Other available public data such as news reports were used to round out the synopsis of the case study.

United Express Flight 5925 was a scheduled commuter passenger flight operated by Great Lakes Airlines with a Beechcraft 1900 twin turboprop. It was a regularly scheduled flight from Chicago O'Hare International Airport to Quincy, Illinois, with an intermediate stop in Burlington, Iowa. Drawing from various first-hand accounts (cockpit voice recorder) and secondary evidence (news reports, archival interview data, and online sources) of the tragedy, the case provides a detailed account of the key events that took place leading up to the accident at Quincy regional airport. The case describes how the radio interactions, a jammed door and degradation of situational awareness all contributed to the accident. Through many of the quotes in the text and eyewitness accounts, readers gain an understanding of the impressions and perceptions of the pilots, including how they felt about many of the critical decisions in the last minutes of the flight and the situation at the airport.

When the authors teach this case, the students are required to read it as pre-reading before class. Various readings and materials (see supplemental readings below and Exhibit 3) are made available to students before class, and the instructor can choose to use some of these materials to further explore areas of interest. This case is best explored over a 90-min session but could be expanded to take up one 3-h session. This case can be covered in an undergraduate senior capstone organizational behaviour seminar, any general organizational behaviour class (including introductory in nature), an undergraduate communication theory class or an MBA class that focuses on applied organizational behaviour concepts. It works particularly well in the MBA class, as students with work experience can make the links between the behaviours explored in the case and their everyday workplaces.

Background: The annual average daily traffic (AADT) data from road segments are critical for roadway projects, especially with the decision-making processes about operations, travel demand, safety-performance evaluation, and maintenance. Regular updates help to determine traffic patterns for decision-making. Unfortunately, the luxury of having permanent recorders on all road segments, especially low-volume roads, is virtually impossible. Consequently, insufficient AADT information is acquired for planning and new developments. A growing number of statistical, mathematical, and machine-learning algorithms have helped estimate AADT data values accurately, to some extent, at both sampled and unsampled locations on low-volume roadways. In some cases, roads with no representative AADT data are resolved with information from roadways with similar traffic patterns.

Methods: This study adopted an integrative approach with a combined systematic literature review (SLR) and meta-analysis (MA) to identify and to evaluate the performance, the sources of error, and possible advantages and disadvantages of the techniques utilized most for estimating AADT data. As a result, an SLR of various peer-reviewed articles and reports was completed to answer four research questions.

Results: The study showed that the most frequent techniques utilized to estimate AADT data on low-volume roadways were regression, artificial neural-network techniques, travel-demand models, the traditional factor approach, and spatial interpolation techniques. These AADT data-estimating methods' performance was subjected to meta-analysis. Three studies were completed: R squared, root means square error, and mean absolute percentage error. The meta-analysis results indicated a mixed summary effect: 1. all studies were equal; 2. all studies were not comparable. However, the integrated qualitative and quantitative approach indicated that spatial-interpolation (Kriging) methods outperformed the others.

Conclusions: Spatial-interpolation methods may be selected over others to generate accurate AADT data by practitioners at all levels for decision making. Besides, the resulting cross-validation statistics give statistics like the other methods' performance measures.

In this study, we illuminate how techniques can be incorporated into interview protocols when conducting research with educational leaders who are being asked to discuss their experiences in crises.

We interviewed seven researchers about their role as a researcher in collecting data on a crisis event from participants. Our analysis concentrated on several key components of the interview.

In presenting our findings on how scholars can adopt a caring and just approach to interview studies with leaders regarding crises, we portray how this approach can be melded into research design, interview protocol and interview techniques.

We illuminate that specific interview techniques are required when interviewing participants who have undergone and survived crises in their work, and we recommend the use of this protocol especially when an interview requires researchers to “handle with care.”

The purpose of this study is to explore how the personal traits of the informal entrepreneurs influence their formalization decisions.

This study adopted a qualitative approach using a multicase design in which 28 informal entrepreneurs situated in Kampala district, Uganda, were engaged. An interview guide, recorders and note books were used in data collection.

The results indicate that the traits of informal and semiformal entrepreneurs are distinct. Informal entrepreneurs have been noted to be more courageous and resilient, while their semiformal counterparts have greater passion for their businesses. It is thus observed that the formalization prospects are higher for the semiformal entrepreneurs than for their informal counterparts. Entrepreneurs that would be willing to formalize their businesses are discouraged by distance, technology and the cost of involving middlemen. Whereas the resilient entrepreneurs are noted to work through these challenges, the passive ones in both the informal and semiformal categories will not formalize their businesses by giving such excuses.

This study contributes to the extant literature on informal entrepreneurship by providing initial empirical evidence on how the personal traits of the entrepreneurs influence their formalization decisions specifically.

The digital age requires people of all ages to communicate and organise their lives through digital technologies. The project EQualCare investigates how the growing population of older people living alone is managing this transition, how it shapes their (non-)digital social networks and what changes on a local level need to be brought about. This paper aims to give insight into the process of participatory action research (PAR) with older people in the community across four countries and reflects on experiences made by academic and co-researchers.

Following the emancipatory underpinnings of PAR, which aims to reduce inequalities through collaboration and co-design, EQualCare involved nine teams of co-researchers across Finland, Germany, Latvia and Sweden making older people the centre of policy development. Co-researchers were involved in formulating research aims, collecting data, reflecting on data, formulating and disseminating recommendations for local policy stakeholders.

Co-researchers’ motivation to invest considerable time and effort was driven by a desire to create a more equal future for older people living alone. Moreover, they were keen to involve marginalised older people and became frustrated when this proved difficult. Power dynamics played a role throughout the process but became productive as roles and responsibilities were renegotiated. Doing PAR with older people can be emotionally challenging for co-researchers when negative feelings around ageing are encountered.

The paper advances understanding on the process of PAR in ageing research by reflecting on the social, cultural and political contexts of doing PAR with diverse sets of older people.

The crane plays an essential role in modern construction sites as it supports numerous operations and activities on-site. Additionally, the crane produces a big amount of data that, if analyzed, could significantly affect productivity, progress monitoring and decision-making in construction projects. This paper aims to show the usability of crane data in tracking the progress of activities on-site.

This paper presents a pattern-based recognition method to detect concrete pouring activities on any concrete-based construction sites. A case study is presented to assess the methodology with a real-life example.

The analysis of the data helped build a theoretical pattern for concrete pouring activities and detect the different phases and progress of these activities. Accordingly, the data become useable to track progress and identify problems in concrete pouring activities.

The paper presents an example for construction practitioners and researcher about a practical and easy way to analyze the big data that comes from cranes and how it is used in tracking projects' progress. The current study focuses only on concrete pouring activities; future studies can include other types of activities and can utilize the data with other building methods to improve construction productivity.

The proposed approach is supposed to be simultaneously efficient in terms of concrete pouring detection as well as cost-effective. Construction practitioners could track concrete activities using an already-embedded monitoring device.

While several studies in the literature targeted the optimization of crane operations and of mitigating hazards through automation and sensing, the opportunity of using cranes as progress trackers is yet to be fully exploited.

In this article, I explore how critical realism influenced the methods and methodology as well as the translations of interviews from Japanese into English and the interpretations of teachers’ understanding of the school at the center of this research.

This article investigates the interaction of critical realism within an English-language-based study of a Japanese high school using ethnographic methods and methodology and its influence on translations within the study. Critical realism combines a postpositivist ontological view with an epistemological constructionism. There is a reality to the school, which cannot be completely measured. This reality, the physical dimensions and composition (breadth, height, volume and number of classrooms) of the school, does not change based upon time or viewing location of an observer.

Critical realism provided strategies for and a focus on the translation of participant interviews from Japanese into English within this ethnographic study of a high school in Japan. These helped to provide a better understanding of the teachers' perception of the reality of the school.

This is original research.

In this chapter, we present a collaborative autoethnographic study with two main layers: first, we share experiences of two separate educational research projects and explore how different dialogic research practices facilitate both participants and researchers to discover the phenomenon being studied; second, we engage in a dialogic conversation to discover our own research practices. Focussing on projects in two different countries (Norway and Canada), our initial centring question for this chapter is: how do our research practices facilitate insight into participants’ real-life experiences and practices? Then turning the light on our own research practices, we ask: what onto-epistemological assumptions shape our dialogical research practices? The chapter reveals that dialogic research practices allowed collective wisdom to be discovered and ensured that we were able to break through the taken-for-grantedness both of the concept being studied and of our own research practices.