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The purpose of this paper is to develop and analyze a new multiple hypothesis receiver autonomous integrity monitoring (RAIM) algorithm, which can handle simultaneous multiple ramp failures.

The proposed algorithm uses measurement residuals and satellite observation matrices of several consecutive epochs for failure detection and exclusion. It detects failures by monitoring the error vector rather than a projection of the error vector. The algorithm assumes that magnitude of range errors can vary with time, while the conventional sequential multiple hypothesis RAIM algorithm assumes that range errors are constant biases.

The algorithm can detect any instance of multiple failures, including failures that cannot be detected by the conventional RAIM algorithm. It can detect multiple failures with magnitudes of several tens of meters, even though the algorithm must solve an ill-conditioned problem. And it can also deal with ramp failures which cannot be detected by conventional sequential multiple hypothesis RAIM algorithm. The detection capability of the proposed algorithm is not dependent on satellite geometry or types of errors.

Implications for the development of the RAIM algorithm for aviation users are included. In particular, it can be a candidate for a future standard architecture in multiple constellations, multiple frequency and satellite-based augmentation system users.

A new multiple hypothesis RAIM algorithm with a relative RAIM concept is proposed. Also presented is a detailed explanation of the algorithms, including rigorous mathematical expressions, and an analysis of differences in detection capability between the conventional multiple hypothesis RAIM algorithm and proposed algorithm.

This paper aims to propose a low-power complementary MOS (CMOS) current sensor for control circuit in an integrated DC-DC buck converter.

The integrated DC-DC converter, which is composed of feedback control circuit and power block, is designed with 0.35-µm CMOS process. Current sensor in the control circuit is integrated with sense-FET and voltage-follower circuits to reduce power consumption and improve its sensing accuracy. In the current-sensing circuit, the size ratio of the power metal oxide semiconductor field effect transistor (MOSFET) to the sensing transistor (K) is 1,000, and a current-mirror is used for a voltage follower. N-channel MOS acts as a switching device in the current-sensing circuit, where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time.

Experiment shows that the current sensor is operated with accuracy of more than 85 per cent, and the transient time of the error amplifier is controlled within 100 µs. The sensing current is in the range of a few hundred µA at a frequency of 0.6-2 MHz and an input voltage of 3-5 V. The output voltage is obtained as expected with the ripple ratio within 5 per cent.

The proposed current sensor in DC-DC converter provides an accurately sensed inductor current with a significant reduction in power consumption in the range of 0.2 mW. High-accuracy regulation is obtained using the proposed current sensor. As the sensor utilizes simple switch-type voltage follower and sense-FET, it can be widely applied to other low-power applications such as high-frequency oscillator and over-current protection circuit.

The paper aims to design of dual-mode boost converter with integrated low-voltage control circuit is introduced in this paper. The paper aims to discuss these issues.

The converter is operated either with LC filter or with charge pump circuit by the switch control. The control stage with error amplifier, comparator, and oscillator is designed with the supply voltage of 3.3 V and the operating frequency of 5.5 MHz. The compensator circuit exploits a pole compensation for a stable operation.

The simulation test in 0.35 μm CMOS process shows that the charge pump regulator and DC-DC boost converter are accurately controlled with the variation of number of stages and duty ratio. The output-voltage is obtained to be 6-15 V within the ripple ratio of 5 percent. Maximum power consumption is about 0.65 W.

This dual-mode is useful in the converter with a wide load-current variation. The advantage of the dual-mode converter is that it can be used in either high or low load current with a simple switch control. Furthermore, in charge pump regulator, there is no degradation of output voltage because of the feedback control circuit.

The purpose of this paper is to investigate the aircraft pushback operations to predict and manage human errors, particularly those associated with the complex team work of carrying out the pushback operation. This should improve air ramp operations reliability.

The study applied the human reliability assessment “Systematic Human Error Reduction and Prediction Approach” that involved a total of 60 semi-structured interviews with practicing experts. Past ramp accident reports were also reviewed to provide more in-depth insights to the problem.

Some of the key performance reliability-degrading errors identified relate to some frequent critical technical inabilities within the team of headset operator and tug driver, as well as the vulnerable intra-team communications. Several best practices were similarly identified.

Based on its findings, this study proposes a new technological concept that can help enhancing safety of aircraft pushback operations. This should enhance reliability of aircraft ground handling and improve aircraft availability. It also provided a generic methodological approach to improve safety-critical operations within high-risk industries.

This study responses to the increasing trend in ramp accidents worldwide.

The research conducted to date in this area is still quite limited compared to that of flight and aircraft maintenance safety. The relevant existing studies focus more on ramp safety holistically, and do not go into the details of how safety and reliability of a ramp operation can be improved. The current paper aims at filling this gap.

This research has the potential to contribute to the understanding of the sustainable ground handling operations framework. Ramp operations as the main system of ground handling include critical services for aircraft/airlines. The purpose of this study is to identify the risk factors in ramp operations for all related stakeholders’ awareness to enhance flight safety. Classifying risk factors, the four main performance fields under risk taxonomy is determined. Thus, managers may allocate resources effectively to handle related threats for corporate sustainability.

New taxonomy with human performance value indicators, which sources from the environment is developed. New developed taxonomy is entitled as “environmental value approach,” which represents environmental value-based approach. The developed new risk factors taxonomy is divided into groups such as ramp personnel, organizational, sustainability-based risk factors: triple view and ergonomics obtained from an extensive literature review and experts’ opinions in the field of human performance.

The findings of this research show that managers need a risk management-oriented approach to manage the human factor affecting performance and sustainability. The newly developed taxonomy offers not only identifying the sources of unsafe operational risk factors but also using as a decision-support tool to manage risks for achieving their sustainability goals. When managerial decisions are made according to risk taxonomy and managing these risks, then corporate performance and individual performance may improve.

The new taxonomy presents the performance-based management of the human factor with a holistic and systematic risk management-based approach. There is no risk taxonomy study designed considering ramp operations and sustainability-based human factor performance.

On-ramp merging areas are typical bottlenecks in the freeway network since merging on-ramp vehicles may cause intensive disturbances on the mainline traffic flow and lead to various negative impacts on traffic efficiency and safety. The connected and autonomous vehicles (CAVs), with their capabilities of real-time communication and precise motion control, hold a great potential to facilitate ramp merging operation through enhanced coordination strategies. This paper aims to present a comprehensive review of the existing ramp merging strategies leveraging CAVs, focusing on the latest trends and developments in the research field.

The review comprehensively covers 44 papers recently published in leading transportation journals. Based on the application context, control strategies are categorized into three categories: merging into sing-lane freeways with total CAVs, merging into sing-lane freeways with mixed traffic flows and merging into multilane freeways.

Relevant literature is reviewed regarding the required technologies, control decision level, applied methods and impacts on traffic performance. More importantly, the authors identify the existing research gaps and provide insightful discussions on the potential and promising directions for future research based on the review, which facilitates further advancement in this research topic.

Many strategies based on the communication and automation capabilities of CAVs have been developed over the past decades, devoted to facilitating the merging/lane-changing maneuvers at freeway on-ramps. Despite the significant progress made, an up-to-date review covering these latest developments is missing to the authors’ best knowledge. This paper conducts a thorough review of the cooperation/coordination strategies that facilitate freeway on-ramp merging using CAVs, focusing on the latest developments in this field. Based on the review, the authors identify the existing research gaps in CAV ramp merging and discuss the potential and promising future research directions to address the gaps.

This paper seeks to identify information enabling and supporting production ramp‐up processes, by exploring critical events and the role of information in such events.

The research approach was based on empirical and theoretical investigations. A selection of 30 events, considered the most critical for production ramp‐up realization and/or performance at one Swedish automotive company, were categorized and constituted the base for the analysis which focused information types and sources enabling event handling.

Information enabling event handling is a balanced combination of problem and domain information, regardless of event category. However, a differentiation concerning preference and usage of information types between experienced and less experienced personnel is identified. Problem‐solving information has the character of pragmatic information, composed of complementary parts of confirmation and novelty in terms of domain and problem information. The preferred information source in all event categories was “other people”.

The study focuses on the application of information in relation to critical events during production ramp‐up. General information theory is not addressed in depth.

Information type and information source are not dependent on certain event categories, which allows a general information strategy enabling production ramp‐up. To facilitate production ramp‐up and event handling managers and key personnel need to apply a holistic perspective and need to be updated on domain information of the products, the equipment, and the production process during production ramp‐up.

The originality is in the focus and role of information to achieve an efficient production ramp‐up performance. A supporting model is developed which describes the structure of pragmatic information for personnel with various levels of experience, regardless of event category.