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This paper aims to characterize the mineral composition of Martian surfaces based on Thermal Emission Spectrometer (TES; Mars Global Surveyor) as measured in the infrared thermal range. It presents modeling and interpreting of TES spectral data from selected Martian regions from which the atmospheric influences had been removed using radiative transfer algorithm and deconvolution algorithm. The spectra from the dark area of Cimmeria Terra and the bright Isidis Planitia were developed in Philip Christensen’s and Joshua Bandfield’s publications, where these spectra were subjected to spectral deconvolution to estimate the mineral composition of the Martian surface. The results of the analyses of these spectra were used for the modeling of dusty and non-dusty surface of Mars. As an additional source, the mineral compositions of Polish basalts and mafic rocks were used for these surfaces as well as for modeling Martian meteorites Shergottites, Nakhlites and Chassignites. Finally, the spectra for the modeling of the Hellas region were obtained from the Planetary Fourier Spectrometer (PFS) – (Mars Express) and the mineralogical compositions of basalts from the southern part of Poland were used for this purpose. The Hellas region was modeled also using simulated Martian soil samples Phyllosilicatic Mars Regolith Simulant and Sulfatic Mars Regolith Simulant, showing as a result that the composition of this selected area has a high content of sulfates. Linear spectral combination was chosen as the best modeling method. The modeling was performed using PFSLook software written in the Space Research Centre of the Polish Academy of Sciences. Additional measurements were made with an infrared spectrometer in thermal infrared spectroscopy, for comparison with the measurements of PFS and TES. The research uses a kind of modeling that successfully matches mineralogical composition to the measured spectrum from the surface of Mars, which is the main goal of the publication. This method is used for areas where sample collection is not yet possible. The areas have been chosen based on public availability of the data.

The infrared spectra of the Martian surface were modeled by applying the linear combination of the spectra of selected minerals, which then are normalized against the measured surface area with previously separated atmosphere. The minerals for modeling are selected based on the expected composition of the Martian rocks, such as basalt. The software used for this purpose was PFSLook, a program written in C++ at the Space Research Centre of the Polish Academy of Sciences, which is based on adding the spectra of minerals in the relevant percentage, resulting in a final spectrum containing 100 per cent of the minerals.

The results of this work confirmed that there is a relationship between the modeled, altered and unaltered, basaltic surface and the measured spectrum from Martian instruments. Spectral deconvolution makes it possible to interpret the measured spectra from areas that are potentially difficult to explore or to choose interesting areas to explore on site. The method is described for mid-infrared because of software availability, but it can be successfully applied to shortwave spectra in near-infrared (NIR) band for data from the currently functioning Martian spectroscopes.

This work is the only one attempting modeling the spectra of the surface of Mars with a separated atmosphere and to determine the mineralogical composition.

The purpose of this paper is to integrate mobile supply and demand on an economic basis and to model the economic value of additional data capacity, spectrum demand and data growth under a range of parameter and policy assumptions.

The modelling requires an iterative solution to find an equilibrium between supply and demand, which allows data demand to be bootstrapped, i.e. determined endogenously within the model.

The sensitivity of the model to input parameter changes differs from a modelling approach where data demand is assumed to be exogenous, whilst in some instances, the sign of the relationship is reversed, e.g. the response of economic value to mobile site cost changes.

The approach suggests a research agenda to estimate willingness to pay for data and the price elasticity of data demand, and may also suggest new explanatory variables to test econometrically in relation to spectrum value.

The approach provides a different route to spectrum valuation and allows estimation of the economic impacts of a range of policy questions.

This paper provides the integration of supply and demand and endogenous estimation of data demand and economic value, coupled with quantitative assessment of a range of policy questions.

The aim of this paper is to consider whether it is possible to identify the future spectrum bands most suitable for the Internet of Things (IoT) from the operating factors of a novel set of radio services for a very wide range of applications, as an aid to policy makers now facing decisions in this area.

The approach uses characteristics of spectrum bands against the applications’ requirements to focus on specific major traits that can be matched.

The main choice factors for spectrum are the practical application needs and the network cost model, and these are fairly useful as matching parameters. It is forecast that multiple bands will be needed and that these should be of a licence-exempt form to seed the unfettered innovation of IoT technologies and pre-empt the formation of significant market power by concerned interests.

The way in which spectrum is allocated today will need to be reconsidered, in the light of evolving IoT requirements, which will have increasing economic and social impacts. Policy recommendations for IoT spectrum demands are outlined, and key policy options to ensure a dynamic and trustworthy development of the IoT are put forward. For instance, regulatory barriers globally will need to be removed.

Current interests in the technical requirements of the IoT have not yet given a suitable analysis of the potential spectrum uses, because too often, it is assumed that previous models of spectrum allocation will continue in the future, without consideration of the economic pressures and social context.

A huge variety of devices accumulates as well distributes a large quantity of data either with the help of wired networks or wireless networks to implement a wide variety of application scenarios. The spectrum resources on the other hand become extremely unavailable with the development of communication devices and thereby making it difficult to transmit data on time.

The spectrum resources on the other hand become extremely unavailable with the development of communication devices and thereby making it difficult to transmit data on time. Therefore, the technology of cognitive radio (CR) is considered as one of the efficient solutions for addressing the drawbacks of spectrum distribution whereas the secondary user (SU) performance is significantly influenced by the spatiotemporal instability of spectrum.

As a result, the technique of the hybrid filter detection network model (HFDNM) is suggested in this research work under various SU relationships in the networks of CR. Furthermore, a technique of hybrid filter detection was recommended in this work to enhance the performance of idle spectrum applications. When compared to other existing techniques, the suggested research work achieves enhanced efficiency with respect to both throughputs as well as delay.

The proposed HFDNM improved the transmission delay at 3 SUs with 0.004 s/message and 0.008 s/message when compared with existing NCNC and NNC methods in case of number of SUs and also improved 0.02 s/message and 0.08 s/message when compared with the existing methods of NCNC and NNC in case of channel loss probability at 0.3.

This paper seeks to examine current trends in spectrum management and implications for developing countries.

The paper summarizes the findings of an extensive review of recent literature on spectrum management. It addresses three questions: What is the case for spectrum management reform? What is the current debate on spectrum management all about? Why does this matter to developing countries?

Traditional spectrum management practice has led to technical and economic inefficiencies as well as obstacles to technological innovation. Two alternative approaches are being tried, one driven by the market (spectrum property rights) and another driven by technology innovation (commons). Practical solutions are evolving that combine some features of both. Although these changes are mainly taking place in high‐income countries, they are deeply relevant to developing countries as well.

Improving traditional administration of the spectrum in many developing countries would yield significant benefits, but governments may wish to consider moving straight into property rights or commons approaches. Countries at an early stage of building up spectrum management capacity may benefit from adopting new solutions from the start. These may be especially well suited for low‐ and middle‐income countries.

The paper offers a concise overview of major current trends in spectrum management, against which the responses of developing countries can be examined. The paper is extensively annotated and includes a selection of references, many of which are accessible online.

An aspect of spectrum reform receiving increasing attention is the introduction of secondary markets for spectrum in order to enable more flexibility to reassign unused and underused spectrum to users that will use it more efficiently. This paper proposes to focus on the policy issues relating to the development of well‐functioning secondary markets for spectrum.

The paper reviews developments in the debate over secondary markets for spectrum. It draws together key elements from the academic literature, various government and government‐commissioned reports, and the practical experience of the few countries that have already introduced spectrum trading. There is considerable focus on concerns and potential costs relating to the introduction of spectrum trading and liberalisation. This has a constructive aim – to draw attention to the need to address such concerns in order to facilitate the development of spectrum trading.

While there is a persuasive case for spectrum trading, countries have been slow to introduce it because of a number of concerns. This paper identifies these concerns and the regulatory framework/policies needed to address them.

The paper distils the policy issues in the debate over spectrum trading and identifies the role that regulators will need to play in the introduction, facilitation and regulation of secondary markets for spectrum.

A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.

In response to calls to critically analyse and conceptually advance social enterprise, the purpose of this paper is to examine narratives and models representing a spectrum of social enterprise from the “social” to the “economic”. The paper tests these against the experience of practitioners who were either employees in social organisations or support workers tasked with promoting social enterprise. This is timely against a background of imperatives from central governments for social organisations to compete for the delivery of public services and become more “entrepreneurial”.

The paper reports qualitative research in which participants were invited to draw lines and arrows onto spectrum models to illustrate the social and economic contexts they perceived themselves to be working within. The data comprise interviews and drawings, combined with verbal descriptions of the drawings and reflections on their significance.

The paper shows how participants interpreted the “social” and “economic” of social enterprise in pictures and words. The research suggests that social enterprise can not be told as a single narrative but as a set of little stories showing oscillations, contradictions and paradox.

Understanding of social enterprise can be much improved by giving greater recognition to ambiguities and compromises within the lived experience of contemporary practice.

The article offers new reflection on widely used images that represent social enterprise along a dichotomous, polar spectrum from social to economic.

The purpose of this paper is to compare three models of employee ownership and to identify pros and cons in relation to how the models can overcome the barriers. Which choices are important when defining the overall rules around the models and the specific possibilities for variations and combinations and what are the pros and cons for these choices?

The comparison is based on the three main models of employee ownership identified from the country descriptions in this special issue.

The models do not exclude each other. The models can all be promoted in a specific country, leaving the choice of specific model to the stakeholders involved in the establishment of the employee-owned company. The article also shows the possibility of combining different models and in this way to adjust to specific preferences and conditions – e.g. whether employees and other stakeholders want collective or individual ownership and whether it concerns a start-up or a succession company.

This paper identified the key differences and similarities of different models for employee ownership including pros and cons of worker cooperative vs the Employee Ownership Trust (EOT) and the Employee Stock Ownership Plan (ESOP) models.

The paper aims to test the spectral line-based weighted sum of gray gases (SLW) method in axisymmetric geometries with particles and high temperature gradients.

An SLW model is coupled with Trivic’s mean wavelength approach to estimate the radiative heat fluxes at the wall of an enclosure and to the base wall of the rocket exhaust, thereby subsequently studying the effect of concentration variation of the gases and particles in these cases. Radiative transfer equation is solved using modified discrete ordinates method. Anisotropic scattering is modeled using transport approximation.

Two cases considered show the importance of particle emission and scattering in the rocket plume base heating problems. In cases involving only gases, the concentration of H₂O tends to have more impact on the flux values than any other gas.

A full model of gases with particles in an axially varying temperature field is reported. Such cases are very common in practical applications. The present methodology gives more insight and a firm handle on the problem vis-a-vis other traditional techniques.