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The upcoming stricter limitations on both pollutant and greenhouse gases emissions represent a challenge for the shipping sector. The entire ship design process requires an approach to innovation, with a particular focus on both the fuel choice and the power generation system. Among the possible alternatives, natural gas and hydrogen based propulsion systems seem to be promising in the medium and long term. Nonetheless, natural gas and hydrogen storage still represents a problem in terms of cargo volume reduction. This paper focuses on the storage issue, considering compressed gases, and presents an innovative solution, which has been developed in the European project GASVESSEL® that allows to store gaseous fuels with an energy density higher than conventional intermediate pressure containment systems. After a general overview of natural gas and hydrogen as fuels for shipping, a case study of a small Roll-on/Roll-off passenger ferry retrofit is proposed. The study analyses the technical feasibility of the installation of a hybrid power system with batteries and polymer electrolyte membrane fuel cells, fuelled by hydrogen. In particular, a process simulation model has been implemented to assess the quantity of hydrogen that can be stored on board, taking into account boundary conditions such as filling time, on shore storage capacity and cylinder wall temperature. The simulation results show that, if the fuel cells system is run continuously at steady state, to cover the energy need for one day of operation 140 kg of hydrogen are required. Using the innovative pressure cylinder at a storage pressure of 300 bar the volume required by the storage system, assessed on the basis of the containment system outer dimensions, is resulted to be 15.2 m3 with a weight of 2.5 ton. Even if the innovative type of pressure cylinder allows to reach an energy density higher than conventional intermediate pressure cylinders, the volume necessary to store a quantity of energy typical for the shipping sector is many times higher than that required by conventional fuels today used. The analysis points out, as expected, that the filling process is critical to maximize the stored hydrogen mass and that it is critical to measure the temperature of the cylinder walls in order not to exceed the material limits. Nevertheless, for specific application such as the one considered in the paper, the introduction of gaseous hydrogen as fuel, can be considered for implementing zero local emission propulsion system in the medium term. [ABSTRACT FROM AUTHOR]

Background: Norway is facing the challenge of reducing transport emissions. High speed crafts (HSC) are the means of transport with highest emissions. Currently there is little literature or experience of using hydrogen systems for HSC. Objective: Evaluate the economic feasibility of fuel cell (FC) powered HSC vs diesel and biodiesel today, and in a future scenario, based on real world operation profile. Method: Historical AIS position data from the route combined with the speed-power characteristics of a concept vessel was used to identify the energy and power demand. From the resulting data a suitable FC system was defined, and an economic comparison made based on annual costs including annualized investment and operational costs. Results: HSC with a FC-system has an annual cost of 12.6 MNOK. It is 28% and 12% more expensive than diesel and biodiesel alternative, respectively. A sensitivity analysis with respect to 7 key design parameters indicates that highest impact is made by hull energy efficiency, FC system cost and hydrogen fuel cost. In a future scenario (2025–2030) with moderate technology improvements and cost development, the HSC with FC-systems can become competitive with diesel and cheaper than biodiesel. Conclusions: HSC with FC-systems may reach cost parity with conventional diesel in the period 2025–2030. [ABSTRACT FROM AUTHOR]

In this article the authors analyse to what extent the objectives of the Council of the European Union (EU) and the EU Commission are effectively realized through the ATA Directive. Authors believe that the choice for a Directive is likely not the most effective, while for a substantial period potentially resulting in legal uncertainty regarding the scope of the Directive’s terminology and provisions. The relationship with existing international (tax) treaty obligations is complex as well as with existing income tax Directives. Moreover, the choice for a Directive puts the tax authorities – who have the primary initiative in applying its provisions – in a relative weaker position since under EU law they cannot unlike taxpayers directly apply the Directive’s provisions. Finally, it can be questioned where local tax authorities have the initiative, whether the EU Commission review and monitoring process will be sufficient to safeguard a consistent application of the Directive’s provisions within the EU, creating a level playing field. In view of this, authors conclude that a Regulation or alternatively a peer review mechanism may result in less legal uncertainty and a more effective mechanism to realize the Council of the EU and the EU Commission’s objectives. [ABSTRACT FROM AUTHOR]

Describes the results of an implementation of a Bluetooth radio in a complementary metal oxide semiconductor process. Measured silicon area for a Bluetooth radio which can be considered the smallest; Importance of the issue related to crosstalk-on-silicon.

Hydrogen carriers are attractive alternative fuels for the shipping sector. They are zero-emission, have high energy densities, and are safe, available, and easy to handle. Sodium borohydride, potassium borohydride, dibenzyltoluene, n-ethylcarbazole, and ammoniaborane are hydrogen carriers with high theoretical energy densities. The energy density is paramount to implementing hydrogen carriers as a high energy density enables compact and lightweight storage. The effective energy density depends on integrating heat and masses with energy converters. This combination defines the energy efficiency and, thus, the energy density of the system. This paper addresses the effective energy density of the hydrogen carriers, including the dehydrogenation process. Using a 0D model, we combined the five carriers with two types of fuel cells, namely proton exchange membrane (PEM) and solid oxide fuel cells (SOFC), an internal combustion engine and a gas turbine. N-ethylcarbazole and dibenzyltoluene offer medium energy densities, reaching almost 4 MJ/kg. However, the effective energy density of sodium borohydride and ammoniaborane is very high, up to 15 MJ/kg, including the energy converter. This is similar to the energy density of marine diesel oil combined with an internal combustion engine. Thus, we conclude hydrogen carriers are alternative fuels that deserve more attention because of their strong potential to make shipping zero-emission. [ABSTRACT FROM AUTHOR]

Purpose of investigation – To determine the contribution of variations in orientation of erythrocytes (orientation effect) to the heart synchronous variations in thoracic impedance in impedance cardiography.Design – The blood of four dogs was gradually replaced by stroma free haemoglobin solution, causing a decrease in resistivity and orientation effect. The decrease in orientation effect was used to determine the contribution of the orientation effect using an extended form of the “parallel conductor” model of the thorax (parallel connection of a tissue admittance Yt and a blood conductance Gb).Subjects – Four adult splenectomised mongrel dogs.Measurements and results – Packed cell volume and resistivity at body temperature of every volume of circulating fluid removed was measured. Real and imaginary parts of the transthoracic impedance and the modulus of the heart synchronous impedance variations were measured just before each exchange. The parallel conductor model was extended to account for the influence on Gb of packed cell volume and orientation of erythrocytes. Applying this extended model, the average variations in Gb at a packed cell volume of 40% were estimated to be 7.46%: 3.03% due to volume variations, 4.43% due to orientation effect. After further extending the model to account for the influence of small changes in blood pressure and heart rate, the average volume variations were estimated to range from 2.8% to 3.3% and the average orientation effect from 4.1% to 4.7% at a packed cell volume of 40%.Conclusion – Resistivity of the blood is far from constant and the contributions of variations in blood conductivity and volume to the heart synchronous thoracic impedance are of comparable magnitude.The contribution of the volume variations is the sum of the volume variations in the contributing intrathoracic vessels. The effects of variations in orientation are added up in proportion to the relative volumes of the contributing vessels. The extensions of the parallel conductor model brought out all physiological factors determining the heart synchronous thoracic impedance variations: pulse pressures and flows, mean pressures and flows, compliances of all contributing blood vessels, packed cell volume and heart rate, as well as the relevant properties of blood: the relations between volume, flow and orientation effect and the change in orientation effect during decelerating flow. [ABSTRACT FROM PUBLISHER]

To test one of the assumptions underlying the calculation of stroke volume — namely, that the transthoracic impedance consists of a parallel connection of a tissue impedance and a blood resistance—experiments were carried out on four dogs in which blood was gradually replaced by a stroma free haemoglobin solution, with the purpose of changing the blood resistance while leaving the tissue impedance unchanged. This was accomplished by exchange transfusion in such a way that the volume of the circulating fluid remained constant and the distribution of fluid volume between the fluid compartments was not altered. During the exchange transfusions the mean decrease in resistivity of the circulating fluid was 54%. The packed cell volume and resistivity of every volume of removed circulating fluid were measured. Just before each exchange the real and imaginary parts of the transthoracic impedance were measured. The packed cell volume decreased exponentially with the number of exchanges. This indicates that the circulating fluid volume remained constant during the exchange transfusion. From the packed cell volumes an estimate of the circulating fluid volume was made. Because of the parallel connection all calculations were based on the use of admittance, which is the reciprocal value of impedance. The real and imaginary parts of the transthoracic admittance were calculated from the measured values of the real and imaginary parts of the transthoracic impedance. The real part (thoracic conductance) increased linearly with the conductivity of the circulating fluid whereas the imaginary part (thoracic susceptance) remained constant. This is in agreement with the model. The components of the model were estimated from the values of the thoracic conductance and susceptance. For a packed cell volume of 40% the mean values of the tissue impedance, the blood resistance, and the transthoracic impedance were 46, 712, and 43 Ω respectively. The mean values of the arguments (phase angles) of tissue impedance and thoracic impedance were 12.4° and 11.8° respectively. [ABSTRACT FROM PUBLISHER]

In a paper presented at the Institute of Hospital Engineering Australia's (IHEA) 59th Annual National Conference in Canberra last year, Klaas Visser, of KAV Consulting, examines effective ways to reduce CO2 emissions and water use in hospitals.