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This paper aims to artificially generate seismic accelerograms compatible with the response spectrum imposed as a function of the given environmental parameters such as magnitude, epicentral distance and type of soil. This study is necessary for the non-linear dynamic analysis of structures in regions where real seismic records are not available.

First, a stochastic iterative method is used to estimate the spectral densities of acceleration power from the respective target response spectra. Thereafter, based on the superposition of seismic waves, a subsequent iterative procedure, which implicitly takes into account the non-stationary character of temporal intensity content of strong ground motions, is developed to synthesize, from these power spectral density, the corresponding acceleration time histories. The phase contents of the ground acceleration samples, thus obtained, are generated using a probability density function of phase derivatives with characteristic parameters estimated from seismological considerations. When based on seismic codes spectrum compatible criteria, this procedure can be used to generate strong ground motions for structural design.

The results found show that the forms of acceleration of the target and the simulated signals have similar characteristics in terms of strong motion durations, the peak ground acceleration values, corresponding time of occurrence and also, the corresponding cumulative energy functions follow practically the same pattern of variations.

The aim of this study is to generate seismic accelerograms compatible with regulatory spectra by the composition of the three acceleration duration segments based on environmental parameters (magnitude, epicentral distance and type of soil) and which subsequently serves to control the time envelope of the generated signals, and therefore the random generation of phase derivatives, which has not been previously treated.

A novel frequency domain approach, which combines the pseudo excitation method modified by the authors and multi-domain Fourier transform (PEM-FT), is proposed for analyzing nonstationary random vibration in this paper.

For a structure subjected to a nonstationary random excitation, the closed-form solution of evolutionary power spectral density of the response is derived in frequency domain.

The deterministic process and random process in an evolutionary spectrum are separated effectively using this method during the analysis of nonstationary random vibration of a linear damped system, only modulation function of the system needs to be estimated, which brings about a large saving in computational time.

The method is general and highly flexible as it can deal with various damping types and nonstationary random excitations with different modulation functions.

Analyzes the development of marketing in East European countries. Traces the growth of East Europe's trade with the West from $12.3 billion in 1970 to $37.6 billion in 1979. Highlights eastern Europe as one of the most promising markets to the US. Discusses the broad spectrums of marketing development between eastern countries. Examines the emergence of marketing through four key stages – authoritative systems, directive systems, mixed‐middle systems and integrative systems. Analyzes the differences in the standards of key marketing factors between East and West – e.g. range of products, pricing and advertising. Concludes that due to variations in starting points and differences in development patterns, East European countries are divided between centralization and decentralization. Affirms that unless US international marketers understand the peculiarities of eastern Europe, the US trade record with these potential markets is unlikely to improve.

The European telecommunications landscape has been transformed over the past 25 years, but spectrum management has remained largely unchanged. The paper seeks to highlight the need for a more flexible approach to spectrum management and, in particular, the role of shared spectrum access.

The paper draws on a research study to examine the value of shared spectrum access, based on a review of the literature, a survey of European national regulatory authorities, and scenario analysis.

The paper highlights trends in wireless data growth and, in particular, the impact of 4G cellular mobile technology over the next five years. With pressure also growing on the licence‐exempt bands at 2.4 and 5 GHz, a more flexible approach to spectrum management will be required in future, including light licensing, de‐licensing and spectrum sharing.

The paper brings together a range of evidence to show how the current approach to spectrum management is no longer able to cope with the social and economic demands for the radio spectrum. It should be of value to policy makers, industry analysts and academics.

When disasters occur, the Chinese national or local government and their relevant departments (hereinafter referred to as the government) probably need to acquire emergency supplies from suppliers. Before concluding a transaction, the public officials usually negotiate the quality and price of the emergency supplies with the suppliers. They expect to achieve the best relief effect while the suppliers want to maximize their own interests. Therefore, in order to help the government acquire inexpensive emergency supplies with high quality in a short time, the purpose of this paper is to examine the negotiation process and proposes a negotiation principle for the staff.

This paper first elaborates the characteristics and impact factors of emergency supplies requisition negotiation. Then it establishes a model describing the negotiation on price and quality of emergency supplies between the public officials and suppliers. Afterwards, it proposes an algorithm which can estimate the success rate of the negotiation. Finally, the paper employs the conclusion of the model and algorithm to analyze the emergency supplies requisition negotiation process during the China Lushan earthquake.

This paper proposes a “WRAD” principle of emergency supplies requisition negotiation of public officials in disasters. First, they should ensure the requisition price is not too low. Second, they would widen the difference between the high price and low price. Third, it is best for them to follow the principle of “ascending negotiation and descending choice” while selecting multiple suppliers to negotiate.

This paper establishes a model to study the emergency supplies requisition negotiation process between the public officials and suppliers based on evolutionary game theory. The model assumes that both the public officials and suppliers are not fully rational individuals, and they need time to consult with each other to find out the optimal solution. This paper proposes an innovative action principle of the public officials during the negotiation process which can help it to acquire inexpensive, high-quality, emergency supplies within a short period from the suppliers.

The purpose of this paper is to consider what the author might call the evolution of the evolutionary argument about gangs and, while acknowledging its explanatory power, suggests that gangs may develop in very different ways depending on the available opportunities, pre-existing forms of criminality in the areas in which gangs emerge and global change.

It is based on a review of the relevant literature and interviews with purposive samples of research, criminal justice and social welfare professionals and young people involved in or affected by gang crime. Findings were triangulated with data held by the police and other public authorities.

The term “street gang” includes a wide variety of groupings all of which are involved in some form of crime but with differential levels of organisation and commitment to purely instrumental goals. Gangs may form but not necessarily evolve. Gangs appear to develop in very different ways depending on the available opportunities, pre-existing forms of criminality in the areas in which they emerge and global changes in drugs markets.

The originality of the paper consists in its interrogation of the concept of “gang evolution” and its discussion of the variety of forms and evolutionary trajectories of gangs.

The purpose of this paper is to use nearly a century’s worth of gang research to inform us about modern terrorist groups, specifically the Islamic State of Iraq and Syria (ISIS).

A case study approach is employed, comparing and contrasting the competing theoretical frameworks of gangs and terrorist organisations to understand group structure, demographics, patterns of behaviour (e.g. territoriality, strategic, and instrumental violence), goals, and membership patterns of ISIS.

The qualitative differences of ISIS make them more comparable to street gangs than other terrorist groups.

ISIS, while being qualitatively different from other terrorist groups, actually has many similarities with street gangs allowing for the adaptation of effective gang prevention, intervention, and suppression strategies. This paper highlights how the expansive literature on street gangs is able to inform practical interventions to directly target ISIS and deradicalise potential recruits. By introducing a gang-terror nexus on the crime-terror continuum, this paper provides a useful perspective on the decentralised but dynamic nature of modern era insurgencies. This paper urges similar case studies of terrorist organisations to determine the extent to which they conform to street gang characteristics.

Terrorist groups are often compared to street gangs, yet it has not been until the last few years that gang researchers (Curry, 2011; Decker and Pyrooz, 2011, 2015a, b) have begun to compare and contrast these two deviant group archetypes. The goal of this paper is to use nearly a hundred years of gang research to better equip scholars and practitioners with a broader understanding of terrorism and insurgency in the era of globalisation by presenting a case study of ISIS using a street gang perspective.

This paper aims to examine the influence of the international spectrum management regime on the introduction of flexibility in the national allocation of radiocommunication services. This is achieved through focusing on the main elements of the international regime.

A qualitative inductive methodology is adopted that examines the different elements of the international radiocommunication service allocation framework. Data are drawn from 66 semi-structured interviews with key stakeholders who are actively involved in International Telecommunication Union Radiocommunication Sector discussions.

The international radio regulations (RR) are perceived to be more of a framework for harmonisation that does not constrain the flexibility of countries. Countries are only restricted on their borders with their neighbours, and flexibility is already facilitated through a range of different measures. Moreover, several elements of the RR can be used to achieve both, i.e. to promote flexibility and to restrict the decisions of others.

The international spectrum management regime is not one of the reasons for the unsuccessful practical application of the flexible spectrum property rights concept. This suggests the need for reviewing whether there still is a need for such a concept given the increasing importance of global harmonisation and economies of scales.

This paper sheds light on spectrum property rights from the perspective of the international spectrum management regime. Such a perspective is largely overlooked in the on-going current debate.

With the recent development of science and technology, research on information diffusion has become increasingly important.

To analyze the process of information diffusion, researchers have proposed a framework with graphical evolutionary game theory (EGT) according to the theory of biological evolution.

Through this method, one can study and even predict information diffusion.

This paper summarizes three existing works using graphical EGT to discuss how to obtain the static state and the dynamics of information diffusion in social network.