Optimal quantitative cryptanalysis of permutation-only multimedia ciphers against plaintext attacks

Recently, an image scrambling encryption algorithm of pixel bit based on chaos map was proposed. Considering the algorithm as a typical binary image scrambling/permutation algorithm exerting on plaintext of size M×(8N), this paper proposes a novel optimal method to break it with some known/chosen-plaintexts. The spatial complexity and computational complexity of the attack are only O(32·MN) and O(16·n₀·MN) respectively, where n₀ is the number of known/chosen-plaintexts used. The method can be easily extended to break any permutation-only encryption scheme exerting on plaintext of size M×N and with L different levels of values. The corresponding spatial complexity and computational complexity are only O(MN) and O(⌈log_L(MN)⌉·MN) respectively. In addition, some specific remarks on the performance of the image scrambling encryption algorithm are presented.     

Applying real options analysis to assess cleaner energy development strategies

The energy industry, accounts for the largest portion of CO₂ emissions, is facing the issue of compliance with the national clean energy policy. The methodology for evaluating the energy mix policy is crucial because of the characteristics of lead time embedded with the power generation facilities investment and the uncertainty of future electricity demand. In this paper, a modified binomial model based on sequential compound options, which may account for the lead time and uncertainty as a whole is established, and a numerical example on evaluating the optional strategies and the strategic value of the cleaner energy policy is also presented. It is found that the optimal decision at some nodes in the binomial tree is path dependent, which is different from the standard sequential compound option model with lead time or time lag concept. The proposed modified binomial sequential compound real options model can be generalized and extensively applied to solve the general decision problems that deal with the long lead time of many government policies as well as capital intensive investments.     

Synthesis of layered MCM-22(P) in the presence of hexamethonium cations and its transformation into EUO- and MWW-type zeolites

Layered MCM-22(P) was synthesized in the presence of hexamethonium (HM) cations. Compared to zeolite EU-1 (EUO-type structure), which crystallizes in similar conditions, its formation is favored at high HM concentrations (HM/SiO₂ ≥ 0.3) and in the absence of Na₂O. HM-containing MCM-22(P) was used as starting material for zeolite formation. Upon hydrothermal treatment, HM-MCM-22(P) transforms into zeolite EU-1 and upon calcination into a MWW-type zeolite. Transformation mechanisms were studied by standard characterization techniques such as XRD, SEM and TEM. Catalytic properties of the MWW-type zeolite obtained from this precursor were evaluated in a m-xylene isomerization reaction. Compared to zeolite MCM-22 prepared with hexamethyleneimine, a higher catalytic activity and an increased isomerization selectivity were observed and discussed.     

Different design scenarios related to an open loop groundwater heat pump in a large building: Impact on subsurface and primary energy consumption

A multidisciplinary methodology is proposed for analyzing opportunities to use existing boreholes and an open-loop groundwater heat pump to provide summer cooling needs for large university buildings in Turin (NW Italy). The approach starts from a model of the buildings to determine the time profile of the cooling load. This curve is then coupled with a model of the off-design behaviour of the heat pump, which allows calculation of its energy performance (coefficient of performance, electricity consumption, etc.) as well as profiles of water discharge to the aquifer in terms of mass flow rate and temperature.Covering the peak energy needs of the buildings requires a variable amount of groundwater during the day. This could be provided varying the withdrawals from the aquifer but, as possible alternatives, two storage system solutions are examined: (1) chilled water storage and (2) groundwater storage. Simulations show that in both cases the use of storage systems produces environmental advantages, as the extent of the thermal plume reduces significantly. Moreover, chilled water storage presents a benefit in terms of reduced total primary energy consumption. The additional costs incurred by storage systems could necessitate public funding as well as system optimization.     

Using a MODFLOW grid, generated with GMS, to solve a transport problem with TOUGH2 in complex geological environments: The intertidal deposits of the Venetian Lagoon

The tides of the Venetian Lagoon generally vary between −0.5 and +0.7 m asl. Occasionally, they may reach a maximum of 1.5 m (acqua alta) and a minimum of −0.8 m asl (acqua bassa). Intertidal areas, called “barene,” exist all along the coast of the Lagoon. These areas are characterized by canals that concentrate the flow of water (and the deposition of sands) during the rising and waning of the tides, and that inundate and drain the vegetated areas found between canals (where organic-rich clays are deposited). Therefore, since the area is subject to subsidence, in time, sand dykes (the original canals) become juxtaposed to clayey dykes (the original vegetated areas). In addition, the sands form a continuous hydrogeologic network within the clays, very similar to that of a vascular system that effectively drains the whole “barena” deposits. In order to be effective, measures for monitoring, confining, or remediating the transport of pollutants through this kind of environment must explicitly take into account the geologic complexity. The same complexity must be included in the numerical models that support remediation efforts. At the moment, there appears to be no off-the-shelf graphical interface that is able to manage such complexity for TOUGH2. To attempt to solve this problem we have used a calibrated USGS-MODFLOW model, of the barena of “Passo a Campalto” in the Venetian Lagoon, developed with the GMS graphical interface. The model is made of 42 layers, which, apart from the first layer, are 0.5 m thick; the first layer has the thickness distribution of a dump found on top of the barena deposit at Passo a Campalto. Each layer consists of 100×60 square cells, for a total of 252,000 cells, only about half of which are active. Using a FORTRAN routine, we translate this grid, with all the hydrogeologic boundary conditions, into a TOUGH2 input file, and we provide the additional necessary information for running a TOUGH2 simulation. The results are promising, in that we were able to produce TOUGH2 grids with very complex geology and to run the models with success. For visualization, the results can be imported back into GMS as 3D scatter point sets, or they can be plotted with any adequate plotting software such as MatLab. Developing conceptual and numerical models with an elaborate graphical interface such as GMS effectively allows setting up complex problems while concentrating on their physics.     

The nanostructure and dewetting of block copolymer thin films annealed in different neutral solvents

The morphology of polystyrene‐b‐poly(2‐vinyl pyridine) thin films annealed under various neutral solvents was investigated. The morphological transition depends on the vapor pressure of the solvent, the quantity of the solvent in the film, and annealing time. We introduced the volume fraction of solvent in a film (Q) to correlate these factors to the morphology. At low Q, the amount of solvent that penetrates into the film is limited and it cannot induce enough chain mobility. Thus, thin film shows short stripes or a worm‐like structure. At high Q, the great diffusion of solvent into the film facilitates polymer mobility, leading to an ordered structure. Our results also suggested that the dewetting mechanism of thin film depends on Q. At low Q, dewetting develops via the nucleation and growth. At high Q, the condensation of solvent on the surface removes some polymer and dewetting is dominated by spinodal mechanism. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

Synthesis and photopolymerization of phosphonic acid monomers for applications in compomer materials

Novel methacrylate monomers bearing phosphonic acid groups 1 and 2 as well as new sulfur methacrylates 9 and 10 have been prepared in good yields from thiophenol. They have been fully characterized by ¹H‐NMR, ¹³C‐NMR, ³¹P‐NMR, and HRMS. Their copolymerization with a bis‐GMA : TEGDMA (1 : 1) blend has been investigated with photodifferential scanning calorimetry at 50°C with camphorquinone as a photoinitiator and ethyl 4‐(dimethylamino)benzoate (EDAB) as a coinitiator. The higher the content of acidic monomer 1 or 2 incorporated in the bis‐GMA : TEGDMA (1 : 1) blend, the lower the mixtures reactivity. The phosphonic acid group has been proved to be responsible for this drop of reactivity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

The effect of resin finish on the dimensional stability of cotton knitted fabric

In this article, the effect of resin finish on the degree of set is discussed. Furthermore, the relationship of the degree of set and dimensional stability is analyzed. After relaxation treatments, the yarns in a fabric would be set at a certain level. As the fabric is subjected to prolonged relaxation treatments, the yarn will become more set until the shape of the unraveled yarn is similar to the shape of the loop in the fabric. The yarn that is removed from a knitted fabric has a curvature value close to zero, and the curvature is exactly as the corresponding position at the knitted loop. From previous research, it is known that the degree of set affects the dimensional properties in a plain knitted fabric. In this article, the degree of set increases with resin level. It explains why the resin finish can stabilize the dimensional properties indirectly.     

Profiling selected phytochemicals and nutrients in different tissues of the multipurpose tree Moringa oleifera L., grown in Ghana

The purpose of this new study was to determine the types and levels of major phytochemicals (non-nutrients) and nutrients in the different tissues from vegetative and flowering Moringa oleifera L. an important multipurpose crop. Rhamnose and acetyl-rhamnose-substituted glucosinolates were found in all of the M. oleifera tissues with different profiles depending on the tissue. In addition the tissues of M. oleifera had a relatively complex flavonoid profile consisting of glucosides, rutinosides, malonylglucosides and traces of acetylglucosides of kaempferol, quercetin and isorhamnetin. Fatty acid profiling of the different tissues showed that leaves were rich in palmitic (16:0) and linolenic (18:3) acid whereas seeds were predominated by oleic acid (18:1). Roots were rich in palmitic and oleic acid, whereas stems and twigs predominately contained palmitic acid. Potassium, magnesium and calcium were the predominant minerals in all of the tissues. Low levels of selenium were detected only in whole seeds.