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Industry interest in equity‐based contingent claims models for evaluating credit risky securities has recently surged. These methods assume away valuation uncertainty that exists in practice. This article explores the impact of valuation uncertainty on these contingent claims models, by analyzing how varying levels of model uncertainty bias default probability estimates obtained from standard contingent claims models.

This paper examines whether there are differences in the nature of the price discovery process across established versus emerging stock markets using a twenty-country sample.

The authors analyse security returns for traces of predictability or non-randomness using variance ratio tests, Granger-Causality models and runs tests.

The findings pinpoint at predictabilities which seem inconsistent with market efficiency, and they suggest that the inherent cause of predictability differs across groups.

The authors present empirical evidence which may be used to attain a deeper understanding of the links between predictability and market efficiency, in view of the conflicting evidence in prior literature.

Whilst the pricing process in emerging markets may be hindered by delayed adjustments, in case of established markets it seems that there is a higher tendency for price reversals which could be due to prior over-reactions.

This study presents evidence of substantial differences in predictability across developed and emerging markets which was gleaned through the rigorous application of different empirical tests.

Presents various aspects of price discrimination in the context of services marketing. Provides a mathematical model which takes demand‐related variables, competitive factors and basic costs into consideration. Factors affecting price discrimination are studied under service intrinsic factors and extrinsic/environmental factors. Also presents mathematical models to demonstrate the viability of price discrimination under different capacity utilization and demand constraint scenarios. Finally, provides the managerial implications of the models along with directions for future research.

Planning is concerned primarily with developing strategies that will achieve a desired future. Accordingly, planners frequently prefer to give relatively little attention to recent trends and patterns and therefore to avoid the use of trend projections, time‐series‐analysis techniques, and other such methods. These planners maintain that their objective is to create an environment that will enable them to deviate from historical trends and therefore that history has little value. However, there are several ways in which statistical projections are useful to planners. In this article we will describe some of the more commonly used time‐series techniques and how they can be applied.

The purpose of this paper is to find a closed relation for the phase noise of LC oscillators.

The governing equation of oscillators is generally a stochastic nonlinear differential equation. In this paper, a closed relation for the phase noise of LC oscillators was obtained by approximating the I–V characteristic of the oscillator with third-degree polynomials and analyzing its differential equation.

This relation expresses phase noise directly in terms of circuit parameters, including the sizes of the transistors and the bias. Next, for evaluation, the phase noise of the cross-coupled oscillator without tail current was calculated with the proposed model. In this approach, the obtained equations are expressed independently of technology by combining the obtained phase noise relation and g_m/I_D method.

A technology-independent method using the g_m/I_D method and the closed relationship is provided to calculate phase noise.

This study aims to propose an aerodynamic force decomposition which, for the first time, allows for thrust/drag bookkeeping in two-dimensional viscous and unsteady flows. Lamb vector-based far-field methods are used at the scope, and the paper starts with extending recent steady compressible formulas to the unsteady regime.

Exact vortical force formulas are derived considering inertial or non-inertial frames, viscous or inviscid flows, fixed or moving bodies. Numerical applications to a NACA0012 airfoil oscillating in pure plunging motion are illustrated, considering subsonic and transonic flow regimes. The total force accuracy and sensitivity to the control volume size is first analysed, then the axial force is decomposed and results are compared to the inviscid force (thrust) and to the steady force (drag).

Two total axial force decompositions in thrust and drag contributions are proposed, providing satisfactory results. An additional force decomposition is also formulated, which is independent of the arbitrary pole appearing in vortical formulas. Numerical inaccuracies encountered in inertial reference frames are eliminated, and the extended formulation also allows obtaining an accurate force prediction in presence of shock waves.

No thrust/drag bookkeeping methodology was actually available for oscillating airfoils in viscous and compressible flows.

The purpose of this paper is to provide reference for researchers by reviewing the research advances and trend of agricultural product price forecasting methods in recent years.

This paper reviews the main research methods and their application of forecasting of agricultural product prices, summarizes the application examples of common forecasting methods, and prospects the future research directions.

1) It is the trend to use hybrid models to predict agricultural products prices in the future research; 2) the application of the prediction model based on price influencing factors should be further expanded in the future research; 3) the performance of the model should be evaluated based on DS rather than just error-based metrics in the future research; 4) seasonal adjustment models can be applied to the difficult seasonal forecasting tasks in the agriculture product prices in the future research; 5) hybrid optimization algorithm can be used to improve the prediction performance of the model in the future research.

The methods from this paper can provide reference for researchers, and the research trends proposed at the end of this paper can provide solutions or new research directions for relevant researchers.

Under current conditions, strong sustainable socio-economic development of major metropolitan areas in separate regions and separate countries comparable to them in size is possible with the optimal management of a set of anti-epidemic measures to combat the COVID-19 pandemic. This chapter constructs the first numerical model of the quasi-periodic dynamics of the COVID-19 pandemic. It was created based on the innovative model of the Kondratiev waves developed by the authors in their previous works. The authors found a close approximation between the model and the actual data for the four waves of development of the COVID-19 pandemic in Moscow. It was also noted that this model applies to small countries close in population to Moscow when comparing the correlation and autocorrelation curves. The data calculated by the models indicate the possibility of the practical application of the developed model for metropolitan areas and small countries comparable to them in size and population. Additionally, the model showed the accuracy of the results for such large countries as Russia and the United States.

Planning the development of ports and harbours involves many complex, technical tasks. Various facility designs must be outlined and analysed. Facility locations must be evaluated and sites selected. Environmental issues must be recognised and the impact of port facilities on the environment must be estimated. Traffic and trade levels must be forecast. Port operating procedures must be evaluated to insure proper facility design. Men, material and capital resources must be inventoried to support the budgeting and economic analysis required. Finally, an economic evaluation must be made of the costs and benefits of the development project. Port planners must often develop plans under economic, social and political pressures. These pressures may not allow the time necessary to evaluate fully all the possible facility designs which could be included in the development plan. The computer model and planning methodology outlined briefly in this paper are designed to facilitate the development process by providing an automated planning framework for the rapid, accurate and thorough analysis of alternative port development plans. This port planning model is centred around a dynamic, stochastic digital computer simulation program. It is dynamic in that port operations may be simulated for any desired length of time; thereby providing in minutes estimates of the results of port operations simulated for years. The model is stochastic in that processes which vary randomly in actual port operations are represented to vary in the same way during the simulation. This added realism in the model increases the accuracy of its results. By properly specifying input data planners may evaluate the effect of alternative development plans on the port's operation; however, its use is not limited to development planning only.

During the past decades, journal impact data obtained from the Journal Citation Reports (JCR) have gained relevance in library management, research management and research evaluation. Hence, both information scientists and bibliometricians share the responsibility towards the users of the JCR to analyse the reliability and validity of its measures thoroughly, to indicate pitfalls and to suggest possible improvements. In this article, ageing patterns are examined in ‘formal’ use or impact of all scientific journals processed for the Science Citation Index (SCI) during 1981‐1995. A new classification system of journals in terms of their ageing characteristics is introduced. This system has been applied to as many as 3,098 journals covered by the Science Citation Index. Following an earlier suggestion by Glnzel and Schoepflin, a maturing and a decline phase are distinguished. From an analysis across all subfields it has been concluded that ageing characteristics are primarily specific to the individual journal rather than to the subfield, while the distribution of journals in terms of slowly or rapidly maturing or declining types is specific to the subfield. It is shown that the cited half life (CHL), printed in the JCR, is an inappropriate measure of decline of journal impact. Following earlier work by Line and others, a more adequate parameter of decline is calculated taking into account the size of annual volumes during a range of fifteen years. For 76 per cent of SCI journals the relative difference between this new parameter and the ISI CHL exceeds 5 per cent. The current JCR journal impact factor is proven to be biased towards journals revealing a rapid maturing and decline in impact. Therefore, a longer term impact factor is proposed, as well as a normalised impact statistic, taking into account citation characteristics of the research subfield covered by a journal and the type of documents published in it. When these new measures are combined with the proposed ageing classification system, they provide a significantly improved picture of a journal‘s impact to that obtained from the JCR.