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The purpose of this paper is to generalize the one‐factor mortgage‐backed securities (MBS)‐pricing model proposed by Kariya and Kobayashi to a three‐factor model. The authors describe prepayment behavior due to refinancing and rising housing prices by discrete‐time, no‐arbitrage pricing theory, making an association between prepayment behavior and cash flow patterns.

The structure, rationality and potential for practical use of our model is demonstrated by valuing an MBS via Monte Carlo simulation and then conducting a comparative static analysis.

The proposed model is found to be effective for analysing MBS cash flow patterns, making a decision for bond investments and risk management due to prepayment.

While the one‐factor valuation model Kariya and Kobayashi treated is a basic framework, the generalized model presented in this paper is much more effective for analysing MBS cash flow patterns, making a decision for bond investments and risk management due to prepayment.

This paper aims to present a control strategy that eliminates the longitudinal and lateral drifting movements of the coaxial ducted fan unmanned helicopter (UH) during autonomous take-off and landing and reduce the coupling characteristics between channels of the coaxial UH for its special model structure.

Unidirectional auxiliary surfaces (UAS) for terminal sliding mode controller (TSMC) are designed for the flight control system of the coaxial UH, and a hierarchical flight control strategy is proposed to improve the decoupling ability of the coaxial UH.

It is demonstrated that the proposed height control strategy can solve the longitudinal and lateral movements during autonomous take-off and landing phase. The proposed hierarchical controller can decouple vertical and heading coupling problem which exists in coaxial UH. Furthermore, the confronted UAS-TSMC method can guarantee finite-time convergence and meet the quick flight trim requirements during take-off and landing.

The designed flight control strategy has not implemented in real flight test yet, as all the tests are conducted in the numerical simulation and simulation with a hardware-in-the-loop (HIL) platform.

The designed flight control strategy can solve the common problem of coupling characteristics between channels for coaxial UH, and it has important theoretical basis and reference value for engineering application; the control strategy can meet the demands of engineering practice.

In consideration of the TSMC approach, which can increase the convergence speed of the system state effectively, and the high level of response speed requirements to UH flight trim, the UAS-TSMC method is first applied to the coaxial ducted fan UH flight control. The proposed control strategy is implemented on the UH flight control system, and the HIL simulation clearly demonstrates that a much better performance could be achieved.

The stability of two‐dimensional natural convection of water near its density maximum (cold water) inside a vertical rectangular enclosure with an aspect ratio of eight is investigated via a series of direct numerical simulations. The simulations aim to clarify, under the influence of density inversion, the physical nature of the instability mechanism responsible for the laminar buoyancy‐driven flow transition from a steady state to an oscillatory state in the enclosure filled with cold water. Two values of the density inversion parameter, _m= 0.4 and 0.5, where the density inversion of cold water may exert strong influence on the flow, are considered in the present study. The results show that the transition from steady state to periodically oscillatory convection arises in the cold‐water‐filled enclosure through a Hopf bifurcation. The oscillatory convection in the water‐filled enclosure for both values of _m is found to feature an oscillatory multicellular structure within the contra‐rotating bicellular flow regions. A traveling wave motion accordingly results along the maximum density contour, which demarcates the contra‐rotating bicellular flows in the enclosure. For both cases the nature of transition into unsteadiness is found to be buoyancy‐driven. The critical Rayleigh number for the bifurcation at _m = 0.4 is found to be markedly higher than that at _m = 0.5.

A DISTINCTION must be made at the outset between wage drift—the movement of plant‐level earnings away from centrally negotiated rates of pay; and productivity drift—the movement of plant‐level earnings away from plant productivity. In this paper, I focus on the latter, in the belief that if the factors causing earnings movements at plant level were better understood managers would be in a position, if they wished, to do something to control them.

The authors present a low-cost unmanned aerial vehicle (UAV) for autonomous flight and navigation in GPS-denied environments using an off-the-shelf smartphone as its core on-board processing unit. Thereby, the approach is independent from additional ground hardware and the UAV core unit can be easily replaced with more powerful hardware that simplifies setup updates as well as maintenance. The paper aims to discuss these issues.

The UAV is able to map, locate and navigate in an unknown indoor environment fusing vision-based tracking with inertial and attitude measurements. The authors choose an algorithmic approach for mapping and localization that does not require GPS coverage of the target area; therefore autonomous indoor navigation is made possible.

The authors demonstrate the UAVs capabilities of mapping, localization and navigation in an unknown 2D marker environment. The promising results enable future research on 3D self-localization and dense mapping using mobile hardware as the only on-board processing unit.

The proposed autonomous flight processing pipeline robustly tracks and maps planar markers that need to be distributed throughout the tracking volume.

Due to the cost-effective platform and the flexibility of the software architecture, the approach can play an important role in areas with poor infrastructure (e.g. developing countries) to autonomously perform tasks for search and rescue, inspection and measurements.

The authors provide a low-cost off-the-shelf flight platform that only requires a commercially available mobile device as core processing unit for autonomous flight in GPS-denied areas.

Because presentation formats, i.e. table v. graph, in shopping web sites may promote or inhibit deliberate consumer decision making, it is important to understand the effects of information presentation on deliberateness. This paper seeks to empirically test whether the table format enhances deliberate decision making, while the web map weakens the process. In addition, deliberateness can be influenced by the decision orientation, i.e. emotionally charged or accuracy oriented. Thus, the paper further examines the effect of presentations across these two decision orientations.

Objective and detailed description of the decision process is used to examine the effects. A two (decision orientation: positive emotion v. accuracy) by two (presentation: map v. table) eye‐tracking experiment is designed. Deliberateness is quantified with the information processing pattern summarized from eye movement data. Participants are required to make preferential choices from simple decision tasks.

The results confirm that the table strengthens while the map weakens deliberateness. In addition, this effect is mostly evident across the two decision orientations. An explorative factor analysis further reveals that there are two major attention distribution functions (global v. local) underlying the decision process.

Only simple decision tasks are used in the present study and therefore complex tasks should be introduced to examine the effects in the future.

For consumers, they should become aware that the table facilitates while the map diminishes deliberateness. For web businesses, they may try to strengthen the impulsivity in a web map filled with emotional stimuli.

This research is one of the first attempts to investigate the joint effects of presentations and decision orientations on decision deliberateness in the internet domain. The eye movement data are also valuable because previous studies seldom provided such detailed description of the decision process.

This paper gives a selective review on some recent developments of nonparametric methods in both continuous and discrete time finance, particularly in the areas of nonparametric estimation and testing of diffusion processes, nonparametric testing of parametric diffusion models, nonparametric pricing of derivatives, nonparametric estimation and hypothesis testing for nonlinear pricing kernel, and nonparametric predictability of asset returns. For each financial context, the paper discusses the suitable statistical concepts, models, and modeling procedures, as well as some of their applications to financial data. Their relative strengths and weaknesses are discussed. Much theoretical and empirical research is needed in this area, and more importantly, the paper points to several aspects that deserve further investigation.

This instrumental case study sought to determine how collegiate-level students changed throughout a personal leadership development course. Document analysis of an archived course assignment was employed to analyze the students’ perceptions of their personal leadership development. Four themes emerged from the analysis: (a) self-evolution, (b) cognitive gain, (c) perceived self-awareness, and (d) framework confusion.

Evidence‐based practices (EBPs) are increasingly being implemented in real‐world settings. While intervention effectiveness is dependent on fidelity, interventions are often adapted to service settings according to the needs of stakeholders at multiple levels. This study aims to examine the naturalistic implementation of The Incredible Years (IY) parenting programme in a residential substance abuse treatment programme for pregnant and parenting women.

The study took place in a residential substance abuse treatment programme serving pregnant and parenting women and their children. Participants included 120 female clients. The primary IY facilitator was a master's level counselling psychologist. In person observations of IY sessions were completed by a trained bachelor's level anthropologist. Ethnographic field notes were collected and then coded in keeping with a priori themes and to identify emergent themes. The Parent Group Leader Checklist was used to evaluate quality and integrity of the IY basic parent programme.

Quantitative analyses indicate that fidelity varied by type of checklist activity. Specifically, adherence to the IY programme was highest in beginning topic activities, setup, and home activity review, and lowest in role play, vignettes, and wrap‐up activities. Qualitative analyses revealed a number of adaptations in implementation of IY. Adaptations fit into two broad categories: modification of programme delivery and modification of programme content. Within each of these categories modifications included organisation‐driven adaptations, provider‐driven adaptations, and consumer‐driven adaptations.

Changes to evidence‐based practice generally take two forms – adaptations consistent with model intent and theoretical approach and changes that represent drift from core elements of the EBP. The challenge for implementation science is to develop frameworks in which models can be adapted enough to make them viable for the service context (or the service context adapted to fit the model), yet avoid drift and maintain fidelity. Attending to the complexities of adaptation prior to and during implementation in a planned way is likely to help organisations better utilise EBPs to meet their unique needs while maintaining fidelity.

The paper shows that identification of types of intervention adaptations and drift allows for consideration of systematic approaches, frameworks, and processes to increase adherence during EBP implementation in community mental health and substance abuse treatment settings.