HIx system thermodynamic model for hydrogen production by the sulfur-iodine cycle

The HIx ternary system (H2O – HI – I2) is the latent source of hydrogen for the Sulfur – Iodine thermo-chemical cycle. After analysis of the literature data and models, a homogeneous approach with the Peng-Robinson equation of state used for both the vapor and liquid phase fugacity calculations is proposed for the first time to describe the phase equilibrium of this system. The MHV2 mixing rule is used, with UNIQUAC activity coefficient model combined with of hydrogen iodide solvation by water. This approach is theoretically consistent for HIx separation processes operating above HI critical temperature. Model estimation is done on selected literature vapor – liquid, liquid – liquid, vapor – liquid – liquid and solid – liquid equilibrium data for the ternary system and the three binaries subsystems. Validation is done on the remaining literature data. Results agree well with the published data, but more experimental effort is needed to improve modeling of the HIx system

Relating Maxwell's Demon and Quantitative Analysis of Information Leakage for Practical Imperative Programs

International audienceShannon observed the relation between information entropy and Maxwell demon experiment to come up with information entropy formula. After that, Shannon's entropy formula is widely used to measure information leakage in imperative programs. But in the present work, our aim is to go in a reverse direction and try to find possible Maxwell's demon experimental setup for contemporary practical imperative programs in which variations of Shannon's entropy formula has been applied to measure the information leakage. To establish the relation between the second principle of thermodynamics and quantitative analysis of information leakage, present work models contemporary variations of imperative programs in terms of Maxwell's demon experimental setup. In the present work five contemporary variations of imperative program related to information quantification are identified. They are: (1) information leakage in imperative program (2) imperative multithreaded program (3) point to point leakage in the imperative program (4) imperative program with infinite observation and (5) imperative program in the SOA-based environment. For these variations, minimal work required by an attacker to gain the secret is also calculated using historical Maxwell's demon experiment. To model the experimental setup of Maxwell's demon, non-interference security policy is used. In the present work, imperative programs with one-bit secret information have been considered to avoid the complexity. The findings of the present work from the history of physics can be utilized in many areas related to information flow of physical computing, nano-computing, quantum computing, biological computing, energy dissipation in computing and computing power analysis

Building a Static Farm Level Spatial Microsimulation Model: Statistically Matching the Irish National Farm Survey to the Irish Census of Agriculture

This paper looks at the statistical matching technique used to match the Irish Census of Agriculture to the Irish National Farm Survey (NFS) to produce a farm level static spatial microsimulation model of Irish agriculture. The match produces a spatially disaggregated population microdata set of farm households for all of Ireland. Using statistical matching techniques, economists can now create more attribute rich datasets by matching across the common variables in two or more datasets. Static spatial microsimulation then uses these synthetic datasets to analyse the relationships among regions and localities and to project the spatial implications of economic development and policy changes in rural areas. The Irish agriculture microsimulation model uses one of many combinational optimatisation techniques - simulated annealing - to match the Census of Agriculture and the NFS. The static model uses this matched NFS and Census information to produce small area (District Electric Divisions (DED)) population microdata estimates for a particular year. Using the matched NFS/Census microdata, this paper will then analysis the regional farm income distribution for Ireland.

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 33)

Abstracts are provided for 16 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1988 through June 1988. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

Privacy protocols

Security protocols enable secure communication over insecure channels. Privacy protocols enable private interactions over secure channels. Security protocols set up secure channels using cryptographic primitives. Privacy protocols set up private channels using secure channels. But just like some security protocols can be broken without breaking the underlying cryptography, some privacy protocols can be broken without breaking the underlying security. Such privacy attacks have been used to leverage e-commerce against targeted advertising from the outset; but their depth and scope became apparent only with the overwhelming advent of influence campaigns in politics. The blurred boundaries between privacy protocols and privacy attacks present a new challenge for protocol analysis. Covert channels turn out to be concealed not only below overt channels, but also above: subversions, and the level-below attacks are supplemented by sublimations and the level-above attacks.Comment: 38 pages, 6 figure

Designing And Testing An Air-PCM Heat Exchanger For Building Ventilation Application Coupled To Energy Storage

Due to the increase of energy costs, buildings energy consumption has tended to decrease in the past decades. This gives an opportunity for developing innovative renewable technologies that are more adapted to recent buildings with low energy demand. In this context, one main challenge is to manage non-simultaneous availability of heat source or sink and the energy demand of buildings. Hence, different technologies dedicated to energy storage have been developed recently; one of them is the use of Phase Change Materials (PCM). These materials are considered because they exhibit a high latent energy and a tunable phase change temperature according to their composition. This paper studies a PCM heat exchanger coupled to a building ventilation system. This PCM module can either store heat during the day (e.g. by cooling solar PV panels) and restore it to the building during the night for space heating purposes or store coolness during the night and give it back during the day and thus act as a free cooling system. This project aims to develop a performing air-PCM heat exchanger providing latent energy storage of 0.5 kWh, this energy is delivered between 15 and 30°C. This heat exchanger is based on corrugated cells that can be easily filled, lined up and then locked in a box, letting the air pass between the cells. The PCM used for the prototype is mainly composed of paraffin. In order to develop an efficient PCM ventilation module, two different ways of investigation were followed and used in parallel. The first one used CFD simulations and the second one, a semi-empirical model based on correlations. The CFD simulations were able to predict the convection coefficient on the air side and also show the flow repartition between the different channels whereas the semi-empirical model allowed a parametrical study in order to identify the best possible geometry. Once the heat exchanger geometry was optimized, a test bench was built and a prototype of air-PCM heat exchanger was manufactured in order to measure its thermal and hydraulic performances. The tests consist in either a complete solidification or liquefaction of the PCM starting from respectively liquid PCM at 30°C or solid PCM at 15°C. The airflow rate was set to 45m³/h, which corresponds barely to the ventilation rate of a traditional room in a residential building. A comparison between the models and the measurements was carried out in order to calibrate the semi-empirical model. Finally, the investigation of a free-cooling application in buildings was performed to calculate the annual performance of the system in different types of climates