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In this work, ZnS-based one-dimensional nanoribbons were synthesized by a simple thermal evaporation method. The highly crystalline fringes exhibit the wurtzite structure, growing mainly along the [001] or [100] direction. The optical absorption spectra showed that the optical absorption band edge of the pure ZnS nanoribbons exhibit an obvious blue shift compared to that of the Mn-doped ZnS. Strong emission band centered at 343 nm has been found from the PL spectrum of the pure ZnS nanoribbons, while a weak defect-related emission centered at 580 nm also was discovered with the dopant of Mn element. Combined with all the measurements, the growth mechanism and the electron transition process were discussed.

The coupled nonlinear Schrodinger equation in parity-time-symmetric coupled waveguides with variable coefficients is studied, and exact combined Peregrine soliton and Akhmediev breather solution is derived. Based on this solution, by adjusting the relation between the maximal value $$Z_{\mathrm{m}}$$ and the exciting location value $$Z_0$$ , we discuss the controllable behaviors including the complete excitation, recurrence, maintenance and restraint of the combined Peregrine soliton and Akhmediev breather.

Layered Double Hydroxides (LDHs) are a family of intercalated functional materials with a layered structure and regarded as an effective modifier to improve the UV ageing resistance of bitumen. However, the preparation of LDHs modified bitumen is very complicated and time-consuming. Based on the theory of Stokes’ law and the equation of the terminal velocity, pre-dispersion and microwave heating were proposed in this research to promote the dispersion of LDHs powder in bitumen matrix. LDHs modified pre-dispersed bitumen (LDHs-PDB) particles were first prepared and then were dispersed in bitumen matrix with the assistance of microwave heating. The cosolvent was optimized and the dispersion of LDHs in the modified bitumen was characterized by the laser particle size analyzer. It is found that the utilization of pre-dispersion alone could slightly improve the dispersion of LDHs in bitumen. The combination of pre-dispersion and microwave heating significantly improved the dispersion of LDHs in bitumen matrix. Although the distribution is still not uniform, it is believed that a reasonable design of the size distribution of LDHs-PDB particles may result in a uniform vertical distribution of particles in bitumen matrix.

Layered double hydroxides (LDHs) modified asphalt is a typical solid-liquid mixture that is concentrated suspensions of solid particles in solutions. The influence of dodecyl benzenesulfonic acid (DBSA) and polyvinyl alcohol (PVA) on the rheological properties and solubility of LDHs modified asphalt (LMA) were investigated by dynamic shear rheometer, molecular dynamic simulations and optical microscopy. Research results indicated that the addition of DBSA or PVA to LDHs modified asphalt resulted in enhancement of the cracking resistance, stress relaxation and creep behavior at lower temperature. The solubility parameters of surface active agent and LMA showed that PVA and DBSA can contribute to the solution of LDHs in asphalt. The effect of PVA was better than DBSA. The morphology of LMA implied that the distribution of LDHs was uniform when 0.5wt-% DBSA or PVA were added and increasing DBSA contents under certain levels increased the uniformity of LDHs..

The comprehensive properties of SBS-modified asphalt mixtures containing layer double hydroxides, including high-temperature stability, water sensitivity, fatigue resistance and low-temperature anti-cracking properties, were studied in this research. It is found that layer double hydroxides–SBS asphalt mixtures show higher retained Marshall stability, freeze-thaw-splitting strength ratio and dynamic stability both before and after ultraviolet aging. It means that the addition of layer double hydroxides to SBS-modified asphalt mixture increases its water damage resistance and rutting resistance. Layer double hydroxides–SBS asphalt mixtures show higher flexural strength and strain than SBS-modified asphalt mixture after ultraviolet aging. It means that the addition of layer double hydroxides improves the long-term low-temperature property of SBS-modified asphalt mixture. The fatigue life of ultraviolet-aged SBS-modified asphalt mixture is also slightly improved by addition of layer double hydroxides...

In this paper, steel slag/steel fiber composite asphalt mixture were prepared. The effects of the addition of steel slag and/or steel fibers on the mechanical, thermal, induction heating and healing properties of asphalt mixture were investigated. The results showed that adding steel slag and/or steel fibers improves the water stability, particle loss resistance and fracture energy of asphalt mixtures. The addition of steel fibers increased the thermal conductivity and thermal diffusion of the asphalt mixture, and steel slag showed a reverse effect. Steel slag asphalt mixture cooled more slowly than steel fiber asphalt mixture, which is beneficial to crack healing of asphalt mixture. The composite of steel fibers and steel slag can enhance the induction heating speed, heating homogeneity and thus enhance the induction healing ratio of asphalt mixture. It is concluded that steel slag/steel fibers composite asphalt mixture achieves good mechanical and induction healing properties.

Cement concrete materials are prone to form internal micro-cracks during service, which can be self-healed via microcapsule method. In this paper, self-healing microcapsules were prepared through melt condensation method with nano-SiO2/paraffin/PE wax composite shell and toluene-di-isocyanate (TDI) healing agent. The core fraction and compactness of microcapsules were measured. Particle size distributions, morphologies, micromechanical properties and chemical structure of microcapsules were characterized by laser particle size analyzer, scanning electron microscopy (SEM), nanoindentation test and Fourier transform infrared spectroscopy (FTIR), respectively. Self-healing capability of mortars containing microcapsules was investigated. The results depicted that core fraction of nano-SiO2/paraffin/PE wax composite shell microcapsule was 72.6%, and the size of the microcapsules was mainly between 400 and 600 µm. Since nano-SiO2 was added to the shell material, the elastic modulus and hardness of the microcapsule reached 1.87 GPA and 61.67 MPa respectively, and the weight loss rate decreased by only 2.6% within 60 d. SEM showed that nano-SiO2/paraffin/PE wax composite shell microcapsules were regular spherical with rough surface, and the shell thickness was about 1/20 of the diameter. The result of FTIR indicated that TDI was encapsulated into the nano-SiO2/paraffin/PE wax composite shell successfully. The compressive strength recovery rate of the mortar containing nano-SiO2/paraffin/PE wax composite shell microcapsules was 87.8% after 60% fc0 pre-load for 10 d self-healing in air. Moreover, the nano-SiO2/paraffin/PE wax composite shell microcapsule could completely self-heal the surface crack of mortar with a maximum width of 0.48 mm within 4 h, which showed that it had good self-healing capability for cracks in cementitious materials.

Ravelling is the main defect of porous asphalt pavement. An unravelling porous asphalt was developed in this research. Steel wool was added to porous asphalt concrete and induction heating was used to heal the cracks at early stage to prevent ravelling. In this paper, the mixing procedure was optimized to disperse steel wool into asphalt mixture, the induction heating potential of porous asphalt concrete containing steel wool was measured, and Rotating Surface Abrasion Test with rest periods to apply induction heating was employed to study the ravelling resistance improvement of porous asphalt concrete. It was found that porous asphalt concrete containing steel wool can be heated with induction energy and induction heating can greatly reduce the stone loss of porous asphalt concrete, despite when induction heating was applied. Porous asphalt suffered less ravelling damage when induction heating was applied at an earlier stage. It is concluded that unravelling porous asphalt can be achieved by applying induction heating and induction should be applied at an early stage.

Ion chelator can improve the self-healing ability of cement-based materials. In this paper, the effects of the mixture of ion chelator and mineral admixture (slag or fly ash) on salt-frost resistance of cement-based materials were investigated. The internal structure and mechanical properties of the mortars with ion chelator and mineral admixture before and after salt-frost cycles as well as curing were studied. The results show that the pore structure, mechanical strength and salt-frost resistance of the mortar mixed with ion chelator and slag are better than those of mortar mixed with ion chelator and fly ash. Compared with the control mortar, the harmful pores (larger than 0.1 mm) ratio of the mortar with ion chealtor and slag declined by 44.5%, while the compressive strength increased by 40.7%. After 100 times salt-frost cycles, the mass loss ratio, harmful pores proportion and compressive strength loss ratio of the mortar with ion chelator and slag had declined by 42.5%, 24.7% and 35% respectively than the control mortar. Curing 28 days after salt-frost, the mortar mixed with ion chelator has good self-healing ability, the compressive strength recovery ratio and harmful pores reduction ratio are 21.18% and 27.04%, respectively. A large amount of needle-like repair products appear in the pores of the mortar mixed with ion chelator. The results of the energy-dispersive spectroscopy and X-ray diffraction tests proved that the main products in the pores and cracks of the mortar are CaCO3 and CaSiO3.

In recent years, nanoparticles with special structures have been widely used in the traditional building material bitumen. For that, mesoporous hollow silica (MHS) particles were synthesized in this work. Scanning electron microscope, transmission electron microscope, and Brunauer-Emmett-Teller tests were conducted to characterize the specific structure. Then, MHS was used to improve the properties of the traditional construction binder material bitumen. Penetration, softening point, and dynamic shear rheometer tests were performed to study the physical and rheological properties of MHS-modified bitumen. A pyrolysis gas chromatography mass spectrometry test was used to evaluate the inhibition effect of MHS on the emission of the bitumen volatile organic compounds (VOCs). The results showed that MHS with continuous distributed pore diameters were simply synthesized in one step by hydrothermal method. MHS as a kind of additive could improve the high temperature rutting resistance of bitumen. In addition, because of the higher specific surface area and massive micropores, MHS had a significant inhibition effect on the emission of bitumen VOCs.

The objective of this paper is to evaluate the healing capacity of steel wool–reinforced porous asphalt concrete. The healing is initiated with induction heating. Bending fracture tests on an elastic foundation are used to prove the healing mechanism. Porous asphalt concrete beams on an elastic foundation were fractured at 5°C; subsequently, they were heated with induction energy, and finally fractured again. The recovered fracture resistance of the beams was used as a healing indicator. Totally fractured porous asphalt beams can regain 78.8% of their bending resistance (strength) when induction heating is applied. It was also found that the optimal heating temperature is 85°C for porous asphalt beams to obtain the highest strength recovery. Reheating of the fractured beams does not decrease the recovery of the flexural resistance, which means that the heating can be repeated when cracks return. On the basis of these findings, it is expected that the healing potential of porous asphalt concrete an...

Asphalt mastic is a self-healing material and it has the potential to close internal cracks by itself. In this study, an induction healing approach is developed to increase the self-healing capacity of asphalt mastic. Conductive additives are added to asphalt mastic to make it electrically conductive and suitable for induction heating. When micro-cracks are expected to occur in asphalt mastic, induction heating can be to improve the self-healing ability of asphalt mastic to close the cracks. This paper investigates the induction heating speed, bending strength and induction healing rate of asphalt mastic with different conductive additives. It was observed that asphalt mastic that contained steel wool or steel fiber can be rapidly heated using induction energy. Adding steel wool or steel fiber to asphalt mastic also increases its bending strength. Finally, the fractured asphalt mastic beams that contain steel wool and steel fiber can regain their bending strength to that of fresh reference samples with induction heating. Cracks were observed to disappear during induction heating. Based on these results, it is concluded that induction heating/healing can be used to close cracks in asphalt mastic.

Ceramic fiber, with a major composition of Al2O3 and SiO2, has advantages of stability at relatively high temperature, big specific surface area and resistance to external mechanical vibration. It has the potential contribution of improving the rutting resistance and temperature sensitivity of modified asphalt binder by proper modification design. In this research, ceramic fiber was introduced into both pen 60/80 and pen 80/100 asphalt binder by different weight ratios. An asphalt penetration test, softening point test, ductility test and dynamic viscoelastic behavior were conducted to characterize and predict the ceramic fiber modified asphalt mortar (CFAM). Research results indicated that the ceramic fiber has a great effect on reinforcement of asphalt, which makes the asphalt stiffer so that the asphalt can only undertake less strain under the same stress. The heat insulation effect of the ceramic fiber will improve the temperature stability. Complex modulus and phase angle results indicate that the ceramic fiber can significantly enhance the high temperature resistance of soft binder.

An induction healing approach was developed to increase the service life of porous asphalt wearing course. Steel wool fibers were mixed in the asphalt mixtures, and then induction heating was applied to heat up the localized steel wool fibers in asphalt mixtures when damage is expected. As a result of induction heating, possible cracks and damages inside porous asphalt can be healed. The objective of this paper is to characterize the field obtained material from an induction healing porous asphalt trial section with laboratory experiments. Heating speed of the field cores was first measured with an infrared camera. It was found that these cores with steel wool can be heated with induction energy. Then, the particle loss value, indirect tensile strength, water sensitivity and nano indentation modulus of the field cores were studied. The results indicate that the addition of steel wool improves the particle loss resistance and ductility of the porous asphalt concrete cores. The mortar phase in porous asphalt core with steel wool shows higher indentation modulus than that in the plain core. These findings imply that steel wool can increase the ravelling resistance of porous asphalt concrete. Finally, the fatigue life extension parameter in four point bending test was applied to investigate the healing potential of this porous asphalt mixture with and without induction heating. The fatigue life of the beams can be greatly extended with induction heating. It was also found that the aged beams can heal much more and faster with induction heating than that with natural healing. Based on these findings, it is expected that the durability of porous asphalt pavement will be improved by the reinforcement of steel wool and induction healing.

It is well known that mastic is a self-healing material and that its self-healing rates are highly influenced by temperature. In [1] it was shown that it is possible to make mastic conductive and to induction-heat it. Additionally, in [2] it was shown that activation energy can be used to calculate the healing times of asphalt mastic through the Arrhenius equation. If the increase of temperature with time could be predicted, the necessary induction heating time to obtain a complete recovery can be calculated. But temperature rise in asphalt mastic through induction heating, depends on a variety of parameters such as ambient temperature, output current and material resistance. For this reason, this paper presents a simple equivalent circuit to represent the thermal heat flow equations for conductive mastic, heated though induction energy. A set of differential equations is derived to calculate the equilibrium temperatures in the mastic surface. Moreover, the model parameters have been derived through the least square method for one induction-heated mixture, which temperature was measured with an infrared camera. Finally, the main induction heating mechanisms in asphalt mastic have been identified and visualized in a foil of fibers and bitumen, which temperature has been increased though induction heating and the results have been compared to those shown in [1] .

The objective of this paper is to evaluate the induction healing effect of steel wool reinforced porous asphalt concrete. The four point bending fatigue resistance of the beams was first studied. It was found that the fatigue resistance of these steel wool reinforced beams was quite good compared with the references in the literature. Then, fatigue life extension ratio and flexural stiffness recovery of the beams were used to show their healing effect. The fatigue life extension ratio was measured after introducing induction heating and letting the fatigue damaged beams rest. It was found that induction heating increases the healing rate of the beams and that the healing is highly microstrain-dependent with higher healing rate under high microstrain level. It was also found that the optimal heating temperature is 85 °C to obtain the best healing effect. Heating too much can cause swelling in the specimens, which will decrease the total healing produced. The fatigue damaged beams obtained extra stiffness recovery when induction heating was applied to them. Finally, it was also found that fatigue life of porous asphalt concrete can be significantly extended by applying multiple induction heating. Based on these findings, it is concluded that the self healing effect of porous asphalt concrete can be increased by induction heating the material. Additionally, the durability of porous asphalt pavement will also be improved with induction healing.

Research on the induction healing of porous asphalt is summarized. Steel wool is added to porous asphalt concrete to make it electrically conductive and suitable for induction heating. When microcracks occur in the material, an induction generator is used to heat the material to close the cracks by the high-temperature self-healing of bitumen. The electrical resistance and induction heating speed of porous asphalt concrete reinforced with steel wool are examined. Porous asphalt concrete containing steel wool is found to be electrically conductive and can be heated with induction energy. The mechanical properties of this porous asphalt are also studied. Steel wool can reinforce porous asphalt concrete by increasing its strength, particle loss (raveling) resistance, and fatigue resistance. Furthermore, the induction healing effect of this porous asphalt concrete reinforced with steel wool is evaluated. It is proved that the fatigue life of induction-healing porous asphalt can be extended significantly by the application of induction heating. It is also found that the optimal heating temperature for the best healing effect is 85°C. These findings indicate that the self-healing potential of porous asphalt concrete and the durability of porous asphalt pavement are improved by induction heating. Finally, a test section was paved on the Dutch A58 motorway with a porous asphalt layer containing steel wool. Because asphalt concrete exhibits better self-healing at higher temperatures, the future for the application of induction-healing porous asphalt concrete appears to be promising.

Pirating various forms of intellectual property (IP) causes great economic loss to intellectual property rights (IPR) holders. IPR protection is becoming a key issue in our highly networked world. In order to further deepen our understanding of how to protect IPR and enhance information interchange and knowledge sharing among related entities, ontologies for IPR protection are proposed. This study contains three parts, which are developed to deal with different perspectives in this domain. The first part presents a static ontology, i.e. a hierarchy framework for the domain language, including primarily classes of participants, classes of IP works, classes of activities, and relations between these classes. In the second part, a dynamic ontology is shown to illustrate the IPR protection process. Thirdly, a causal map is used to demonstrate how classes of IPR protection methodologies are causally related with classes of IP piracy methodologies. Finally, the case of Tomato Garden is offered to demonstrate how the proposed ontologies are used in the real world. In respect of the ontology, it is first helpful to gain a comprehensive understanding of domain knowledge of IPR protection; second, IPR protection systems' design and development in this domain are facilitated and supported by these ontologies; third, the proposed ontologies are united in the Ontology Web Language (OWL) and the OWL rules languages framework, both of which are machine readable.

The objective of this paper is to detect the healing effect of asphalt mastic and porous asphalt concrete caused by induction heating. It was found that the broken mastic beams could be healed many times by induction heating. Moreover, the stiffness of porous asphalt concrete recovered more and faster when induction heating was applied to the samples. It was also found that fatigue life of porous asphalt concrete was significantly extended by induction heating. Based on these findings, it was concluded that the self healing rate of asphalt mastic and porous asphalt concrete can be increased by induction heating.

In recent decades, researchers have revealed the great healing potential of asphalt and proposed various novel methods to inspire and improve the self-healing capacity of asphalt aimed to prolong the service life of asphalt pavement. In this review, up to date research progresses in induction healing and embedded rejuvenator encapsulation are presented, respectively. Meanwhile, the trial section applications of induction healing and capsule healing are highlighted, which show promising results. Finally, some recommendations for the future development of self-healing asphalt are proposed.

In this research, an electrically conductive porous asphalt concrete, used for induction heating, was prepared by adding electrically conductive filler (steel fibers and steel wool) to the mixture. The main purpose of this paper is to examine the electrical conductivity and the indirect tensile strength of this conductive porous asphalt concrete and prove that it can be heated via induction heating. It was found that, to make porous asphalt concrete electrically conductive, long steel wool with small diameter is better than short steel fibers with bigger diameter. However, steel fibers with short length and big diameter have better strength reinforcement capability than steel wool with long length and small diameter. It was also proved that conductive porous asphalt concrete containing steel wool can be easily heated via induction heating. Finally, 10% (by volume of bitumen) of steel wool type 000 was proposed as an optimal content in porous asphalt concrete to obtain an optimal conductivity, a good induction heating rate and an acceptable indirect tensile strength. It is expected that the autogenous healing capacity of asphalt concrete will be enhanced with the increase of temperature during induction heating.

This work aims to develop an original alginate micro-emulsion combining with droplets microfluidic method to produce multinuclear Ca-alginate microcapsules containing rejuvenator for the self-healing of bituminous binder. The sizes of the Ca-alginate microcapsules could be easily controlled by tuning flow rates of the continuous and dispersed phases. The addition of a surfactant Tween80 not only improved the stability of the emulsion, but it also effectively reduced the size of the microcapsules. Size predictive mathematical model of the microcapsules was proposed through the analysis of fluid force. Optical microscope and remote Fourier infrared test confirmed the multinuclear structure of Ca-alginate microcapsules. Thermogravimetric analysis showed that the microcapsules coated with nearly 40% rejuvenator and they remained intact during the preparation of bitumen specimen at 135 °C. Micro self-healing process of bituminous binder with multinuclear Ca-alginate microcapsules containing rejuvenator was monitored and showed enhanced self-healing performance. Tensile stress-recovery test revealed that the recovery rate increased by 32.08% (in the case of 5% microcapsules), which meant that the Ca-alginate microcapsules containing rejuvenator could effectively enhance the self-healing property of bituminous binder.

The lifetime of porous asphalt pavement is only about 11 years. In this research, a porous asphalt concrete with long lifetime, based on a healing mechanism triggered by means of induction heating, is explained. Conductive fillers (steel fibers and steel wool) are added to porous asphalt concrete to enhance its electrical conductivity and induction heating is used to increase the temperature locally, just enough to increase the healing rate of asphalt concrete to heal the micro-cracks and to repair the bond between aggregates and binder. The main purposes of this research are to examine the electrical conductivity, particle loss resistance and induction heating speed of electrically conductive porous asphalt concrete and prove that damage in the material can be healed via induction heating. It is found that long fibers with small diameter are better than short fibers with bigger diameter to make porous asphalt concrete electrically conductive, induction heatable and have high particle loss resist...

The objective of this research is to examine the conductivity of asphalt mortar through the addition of electrically conductive fillers and fibers: graphite and steel wool, and prove that this material can be heated with induction energy. The effect of fibers content, sand–bitumen ratio and the combination of fillers and fibers on the resistivity of asphalt mortar was investigated. It was found that the percolation threshold happened sooner by adding electrically conductive fibers than by adding fillers. Percolation threshold was also found to be function of the sand–bitumen ratio and of the volume of fibers content. There is an optimum content of fibers for each sand–bitumen ratio, above which it is difficult to make the mixture and the electrical resistivity increases exponentially. Besides, in case of adding conductive fillers or a mixture of conductive fibers and fillers to the mastic, once the maximum conductivity is reached, it remains constant, independently of the volume of conductive filler added. Nano CT-scan (computed axial tomography) reconstructions were also used to visualize the fibers connected inside the mixture. Finally, to validate the research, three different samples were induction heated and their temperature variation was measured.

The fatigue properties of asphalts were investigated after various laboratory simulation ageing tests and outdoor natural exposure ultraviolet radiation ageing, by dynamic shear rheometer (DSR) time sweep fatigue test in constant strain model and a new type of specimen which was introduced to avoid the problem of adhesion failure between rotor and asphalt binder. The results show that outdoor natural exposure ageing (NEA) causes the decrease of retained fatigue life distinctly, and photodegradation caused by outdoor NEA of 1 250 μm thin films asphalt for three months, is found to be severer than pressure ageing vessel (PAV) with respects to retained fatigue life. The effect of photodegradation increases as the time of outdoor NEA increases. DSR time sweep fatigue test in constant strain indicates that the aged styrene-butadiene-styrene (SBS) modified asphalt still displays better fatigue properties than the corresponding base asphalt after ageing.

Application of rejuvenation products on porous asphalt pavements as a preventive maintenance technology has been investigated recently by the Dutch Ministry of Transportation. Traditionally, the main contribution of rejuvenators to porous asphalt pavements is considered as restoring its flexibility. Whether this really is the case is investigated in the research reported in this paper. For this purpose, identification of rejuvenators is done using optical microscopy and nanoindentation technology. Visual inspection from optical microscopy shows that all applied rejuvenation products, except for bitumen emulsion BE-1, provide an additional bituminous binder film to the mortar and also fill microcracks. The decrease of indentation modulus of the mortar shows that BE-1 and BE-2 can penetrate into the mortar and improve its flexibility.

In this paper, the ice melting performance of asphalt concrete with steel fibers was studied. Steel fiber modified asphalt mixtures were prepared, five different fiber amount of steel fiber modified asphalt mixtures were mixed to study their induction heating rate. The samples covered with different thickness of ice were heated with induction heating to study their ice melting efficency. It was proved that the induction heating of steel fiber modified asphalt mixtures could significantly improve their ice melting efficency compared with the natural condition. And it was found that the thickness of the ice had little influence on the induction heating rate of the asphalt concrete.

The ice on the surface of asphalt pavement in winter significantly influences the road transportation safety. This paper aims at the improvement of the ice melting efficiency on the surface of asphalt pavement. The steel slag asphalt concrete was prepared and the high ice melting efficiency was achieved with the microwave heating. A series of experiments were conducted to evaluate the ice melting performance of steel slag asphalt concrete, including the heating test, ice melting test, thermal conductivity test and so on. The results indicated that the microwave heating of steel slag concrete can improve the efficiency of deicing, mainly because the heating rates of steel slag asphalt mixture are much better than traditional limestone asphalt mixture. According to different thickness lever of ice, the final temperatures of each sample were very close to each other at the end of melting test. It is believed the thickness of the ice has a limited impact on the ice melting efficiency. According to the heating tests results, the bonding of ice and asphalt concrete is defined failure at the moment when the surface temperature of the ice reached 3 °C.

This paper presents some results from an experiment of image softproofing under different International Color Consortium (ICC) rendering intents, which will be available for selecting an appropriate rendering intent in printing processes. In a screen softproofing procedure, image is converted via ICC profile embedded in image itself to output device profile, then to proofing device profile. With the rendering intent of absolute colorimetry in the second conversion, the effects of different rendering intents in the first conversion have been investigated through a softproofing software developed in Matlab 7.0. A variety of testing images, including light tone, shadow detail, etc., are used for image softproofing. The color differences between original images and proofed images are calculated under the S-CIE L*a*b* color difference formulae. Comparisons and analyses on the obtained images under four rendering intents show the effects of color characteristics of original images on rendering intent selection.

The induction healing concept of porous asphalt was developed at Delft University of Technology and was proven very successful in the laboratory. A porous asphalt test section with this self healing concept was also paved on Dutch highway A58. This special porous asphalt contained 4% steel wool (by volume of bitumen). A number of cores were drilled from this test section to predict its performance. Beams were also prepared with the same materials as used in the test section. Experiments were done on these specimens to study the mechanical, heating and healing properties. It is found in Cantabro test that the particle loss resistance of porous asphalt concrete is improved by addition of steel wool. The improvement in particle loss resistance will delay ravelling on the pavement. It is also proven that the cores containing steel wool can be heated quickly with induction energy. Finally, it is found that the fatigue life of the beamsis extended greatly by applying induction heating during the rest period. The damage (cracking) in the porous asphalt beams ishealed by induction healing. Based on these findings, it is concluded that the life time of the test section will be extended by the reinforcement of steel wool and induction heating.

An electrically conductive porous asphalt concrete used for induction heating and subsequently healing of cracks is prepared by adding conductive materials (steel fibers and steel wool) in this research. In this paper, the optimization of steel fiber used for induction heating is reported based on the electrical resistivity, induction heating speed and particle loss resistance of porous asphalt concrete. It is found that porous asphalt concrete containing steel fiber with smaller diameter or longer steel fiber is more electrically conductive and induction heatable than that containing the same content of steel fiber with bigger diameter or short steel fiber. It is also found that steel wool type 00 with length of 9.5 mm is more effective than short steel fiber type 1 and steel wool type 000 to improve the particle resistance of porous asphalt concrete. Finally, 8% (by volume of bitumen) of steel wool type 00 is considered as the best option used for induction heating in porous asphalt concrete.

Asphalt binder is a self-healing material and it has a potential to heal faster with increased temperatures. This paper investigates the thermally activated healing of fatigue damage in three asphalt binders, trying to answer the question: At what temperatures do asphalt binders heal? After fatiguing the sample, a heating treatment was applied and the sample was fatigued for the second time. The recovered fatigue life and the recovered accumulated dissipated energy are used to quantify the thermally activated healing rates of asphalt binders. It is found that these two healing indexes coincide well with each other in different healing conditions. Base asphalt binders can heal the fatigue damage completely after heating for 20 min at the softening-point temperatures. Styrene–butadiene–styrene (SBS)-modified asphalt binder can achieve full healing at a temperature 20°C below its softening point, where the elastic recovery of the SBS chain segment may play an important role in healing. It is also found that healing of fatigue damage in asphalt binder is highly strain dependent: the healing ratio is higher at high strain amplitude. It proved that thermally activated healing can be repeated when damage returns in asphalt binder. It is concluded that thermally activated healing of fatigue damage is definitely useful to increase the fatigue life of asphalt binders and different asphalt binders should be heated to certain temperatures related to their specific softening points.