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This study presents a preliminary evaluation of the application of Thrust Vectoring (TV) technology for improving windshear recovery of civil aircraft in microburst windshear encounters. A numerical trajectory optimization technique based on the method of multiple shooting is applied to achieve a microburst escape with minimal loss of altitude for a Boeing 727 type aircraft. Although the application of TV does result in a slight improvement in recovery altitude, there is also a price to be paid in the sense that TV utilization significantly hampers the ability to gain specific energy during recovery. Maintaining an energy buffer during a microburst encounter is highly desirable to achieve robustness with respect to uncertainness in windshear size and strength. TV aided windshear recovery has also been compared with an alternative approach to improve the windshear survivability capability, namely, the application of lateral maneuvering. The comparison shows that lateral maneuvering is not only a far more effective means to improve the recovery altitude, it also vastly improves energy preservation. In a view of the results established in this study, we feel that TV does not hold out great promise as a useful means to truly improve windshear recovery.

Research examining the experiences of women in the workplace has, to a large extent, neglected the unique stressors pregnant employees may experience. Stress during pregnancy has been shown consistently to lead to detrimental consequences for the mother and her baby. Using job stress theories, we develop an expanded theoretical model of experienced stress during pregnancy and the potential detrimental health outcomes for the mother and her baby. Our theoretical model includes factors from multiple levels (i.e., individual, interpersonal, sociocultural, and community) and the role they play on the health and well-being of the pregnant employee and her baby. In order to gain a deeper understanding of job stress during pregnancy, we examine three pregnancy-specific organizational stressors (i.e., perceived pregnancy discrimination, pregnancy disclosure, and identity-role conflict) that are unique to pregnant employees. These stressors are argued to be over and above the normal job stressors experienced and they are proposed to result in elevated levels of experienced stress leading to detrimental health outcomes for the mother and baby. The role of resilience resources and learning in reducing some of the negative outcomes from job stressors is also explored.

The chapter introduces the reader to select language of human sexuality and the definitions and characteristics of some key terms related to lesbian, gay, bisexual, transgender, and questioning/queer (LGBTQ+), identifies different theoretical perspectives of human sexuality and sexual orientation, and discusses select LGBTQ+ theories and concepts in a historical context that library and information science (LIS) professionals should consider while performing their roles related to information creation–organization–management–dissemination–research processes. It helps better understand the scope of what is LGBTQ+ information and traces its interdisciplinary connections to reflect on its place within the LIS professions. The chapter discusses these implications with the expectation of the LIS professional to take concrete actions in changing the conditions that lack fairness, equality/equity, justice, and/or human rights for LGBTQ+ people via the use of information. Important considerations in this regard include the need for an integrative interdisciplinary LGBTQ+ information model, growth of a diversified LGBTQ+ knowledge base and experiences, holistic LGBTQ+ information representations, LGBTQ+ activism, and participatory engagement and inclusion of LGBTQ+ users.

The purpose of this paper is to establish the value of clinical genetic diagnostics in the lives of people with an intellectual disability (ID), their families, and their primary and professional caregivers. It has been shown that psychologists are more likely to make use of the opportunities offered by clinical genetic diagnostics if they have seen the psychological benefits in their own practice. Moreover, this paper aims to promote the practice of informing people with ID, their families, and other caregivers regarding the current technological advances in genetic diagnostics, thereby allowing these patients to decide for themselves whether to utilise these opportunities.

The authors report four case studies in which the psychosocial value to each patient is pivotal.

In these four cases, it is clear the medical model can augment the social model by providing an interpretation of its meaningfulness in the lives of the people concerned.

Case studies alone can have limited scientific significance. This approach examining the significance of clinical genetic diagnosis should be studied further in larger groups.

It is hoped that psychologists and other professional caregivers will become enthused about the value of clinical genetic diagnostics and will choose to discuss the option of referral for clinical genetic diagnostics with their patients more often.

People with an ID who are seeking mental health care, and their caregivers, should be given the opportunity to take part in the decision regarding whether to use clinical genetic diagnostics, which may even have a destigmatising effect.

Quality of life may improve for people with an ID seeking mental healthcare and for their caregivers as well by opening up discussion regarding the opportunities presented by clinical genetic diagnostics. The fact that people are able to make their own choices based on their own considerations can have a destigmatising effect.

Wheelchairs and mobility devices are important to enable mobility for students who are unable to functionally walk by themselves to fully participate in daily life. However, they can be enablers or barriers to inclusion and participation for students. Children and adolescents, like other wheelchair users, have a varying number of reasons to use chairs, but what type of chair, how it is used and what type of participation it encourages or discourages is as individual as the child themselves. This is an area of practice that has little evidence on which to base decisions, leading to inconsistencies of provision practice and inclusion in mainstream environments. This chapter will discuss why children use wheelchairs in the first place, then outline some of the typical types of wheelchair available and discuss matching the child to their wheelchair. Barriers to appropriate use of wheelchairs include policy, funding, attitudes and perceived skill set. Children who use wheelchairs often do not gain the motor experiences that their peers do yet are expected to perform skilled wheeled mobility, often without training. Finally, inclusion in school is about inclusion not only in the classroom but also in all activities to do with their school-based communities.

The choice of what type of mobility a child needs is down to their self-defined goals in the context of their school environment, family and general ecosystem. Other forms of wheeled mobility included adaptive bicycles for children who are unable to utilise nonadapted bikes. The basis for assessment for wheeled mobility is the student. The most important part of adaptive seating is to match the student, their self-defined goals and their developmental needs. Barriers to inclusion are discussed. The final section of this chapter includes a discussion of where wheeled mobility is going into the future.

This study aims to propose a new airport gate assignment method to effectively improve the comprehensive operation capacity and efficiency of hub airport. Gate assignment is one of the most important tasks for airport ground operations, which assigns appropriate airport gates with high efficiency reasonable arrangement.

In this paper, on the basis of analyzing the characteristics of airport gates and flights, an efficient multi-objective optimization model of airport gate assignment based on the objectives of the most balanced idle time, the shortest walking distances of passengers and the least number of flights at apron is constructed. Then an improved ant colony optimization (ICQACO) algorithm based on the ant colony collaborative strategy and pheromone update strategy is designed to solve the constructed model to fast realize the gate assignment and obtain a rational and effective gate assignment result for all flights in the different period.

In the designed ICQACO algorithm, the ant colony collaborative strategy is used to avoid the rapid convergence to the local optimal solution, and the pheromone update strategy is used to quickly increase the pheromone amount, eliminate the interference of the poor path and greatly accelerate the convergence speed.

The actual flight data from Guangzhou Baiyun airport of China is selected to verify the feasibility and effectiveness of the constructed multi-objective optimization model and the designed ICQACO algorithm. The experimental results show that the designed ICQACO algorithm can increase the pheromone amount, accelerate the convergence speed and avoid to fall into the local optimal solution. The constructed multi-objective optimization model can effectively improve the comprehensive operation capacity and efficiency. This study is a very meaningful work for airport gate assignment.

An efficient multi-objective optimization model for hub airport gate assignment problem is proposed in this paper. An improved ant colony optimization algorithm based on ant colony collaborative strategy and the pheromone update strategy is deeply studied to speed up the convergence and avoid to fall into the local optimal solution.

In a microburst wind, the profiles and characteristics are significantly different from those of normal boundary layer winds. The objective of this work is to study the microburst effect on the performance of aircraft for providing guidelines to frame escape strategies.

Large eddy simulation model is used to study the effect of microburst by simulating the actual physical process of microburst-generated downdraft environment over the unmanned aerial vehicle. In this work, an attempt has been made to simulate the dry microburst (microburst not accompanied by rain) numerically using the impinging jet model to explore the effect of microburst at 12° angle of attack for flight take-off condition with a Mach number 0.04.

The numerical results revealed the aerodynamic performance loss of an aircraft in the microburst-generated downdraft during take-off condition quantitatively. This could be a more valuable information to the aviation industry. The authors believe that the results shown in this paper will be useful for the designers of aircraft. This will also help train the pilots to control the airplanes in a microburst environment.

Severe thunderstorms are significant weather phenomena that have a significant impact on various facets of national activity, including civil and defence operations, specifically aviation, space vehicle launch and agriculture, in addition to their potential to cause damage to life and property.

The maximum percentage of pressure increases on the upper surface of the aircraft between 2 and 7 s is 99.86% under the microburst-generated downdraft condition. The flight escape maneuver could be initiated, before increasing the pressure on the upper surface of the aircraft. The aircraft flies with high airspeed through the microburst environment, where the microburst-generated downdraft is most severe.

Today’s, supply chain production and distribution of products to improve the customer satisfaction in the shortest possible time by paying the minimum cost, has become the most important challenge in global market. On the other hand, minimizing the total cost of the transportation and distribution is one of the critical items for companies. To handle this challenge, this paper aims to present a multi-objective multi-facility model of green closed-loop supply chain (GCLSC) under uncertain environment. In this model, the proposed GCLSC considers three classes in case of the leading chain and three classes in terms of the recursive chain. The objectives are to maximize the total profit of the GCLSC, satisfaction of demand, the satisfactions of the customers and getting to the proper cost of the consumers, distribution centers and recursive centers.

Then, this model is designed by considering several products under several periods regarding the recovery possibility of products. Finally, to evaluate the proposed model, several numerical examples are randomly designed and then solved using non-dominated sorting genetic algorithm and non-dominated ranking genetic algorithm. Then, they are ranked by TOPSIS along with analytical hierarchy process so-called analytic hierarchy process-technique for order of preference by similarity to ideal solution (AHP-TOPSIS).

The results indicated that non-dominated ranked genetic algorithm (NRGA) algorithm outperforms non-dominated sorting genetic algorithm (NSGA-II) algorithm in terms of computation times. However, in other metrics, any significant difference was not seen. At the end, to rank the algorithms, a multi-criterion decision technique was used. The obtained results of this method indicated that NSGA-II had better performance than ones obtained by NRGA.

This study is motivated by the need of integrating the leading supply chain and retrogressive supply chain. In short, the highlights of the differences of this research with the mentioned studies are as follows: developing multi-objective multi-facility model of fuzzy GCLSC under uncertain environment and integrating the leading supply chain and retrogressive supply chain.

The purpose of this paper is to create a flight route optimization for all flights that aims to minimize the total cost consists of fuel cost, ground delay cost and air delay cost over the fixed route and free route airspaces.

Efficient usage of current available airspace capacity becomes more and more important with the increasing flight demands. The efficient capacity usage of an airspace is generally in contradiction to optimum flight efficiency of a single flight. It can only be achieved with the holistic approach that focusing all flights over mixed airspaces and their routes instead of single flight route optimization for a single airspace. In the scope of this paper, optimization methods were developed to find the best route planning for all flights considering the benefits of all flights not only a single flight. This paper is searching for an optimization to reduce the total cost for all flights in mixed airspaces. With the developed optimization models, the determination of conflict-free optimum routes and delay amounts was achieved with airway capacity and separation minimum constraints in mixed airspaces. The mathematical model and the simulated annealing method were developed for these purposes.

The total cost values for flights were minimized by both developed mathematical model and simulated annealing algorithm. With the mathematical model, a reduction in total route length of 4.13% and a reduction in fuel consumption of 3.95% was achieved in a mixed airspace. The optimization algorithm with simulated annealing has also 3.11% flight distance saving and 3.03% fuel consumption enhancement.

Although the wind condition can change the fuel consumption and flight durations, the paper does not include the wind condition effects. If the wind condition effect is considered, the shortest route may not always cause the least fuel consumption especially under the head wind condition.

The results of this paper show that a flight route optimization as a holistic approach considering the all flight demand information enhances the fuel consumption and flight duration. Because of this reason, the developed optimization model can be effectively used to minimize the fuel consumption and reduce the exhaust emissions of aircraft.

This paper develops the mathematical model and simulated annealing algorithm for the optimization of flight route over the mixed airspaces that compose of fixed and free route airspaces. Each model offers the best available and conflict-free route plan and if necessary required delay amounts for each demanded flight under the airspace capacity, airspace route structure and used separation minimum for each airspace.

Control laws that are based on the nonlinear inverse dynamics (NID) of the aircraft offer the potential for providing improved levels of performance over conventional flight control designs. The NID and its application in the flight control during windshear penetration are introduced here. With the employment of a real engineering windshear model and NID, a low‐altitude windshear penetration flight control law is designed. The simulative calculation results indicated that the NID control logic works effectively in the trajectory control of the aircraft during the penetration of windshear.